Tag: gardening

Ground Beetle

Ground beetles are apex predators of the teeming communities of invertebrates that inhabit the soil under logs, rocks, and leaf litter.

Common Name: Ground Beetle, Black Ground Beetle, Common Black Ground Beetle – Beetle, as insect, is of Old English origin as bitula from bitan a verb meaning “to bite”. This eventually devolved to bityl in Middle English, with the same pronunciation as the current spelling. Beetle can also mean a heavy wooden mallet in which case it is derived from the Old English bietel, which is derived from the verb “to beat”, as in Beatles [1]

Scientific Name: Pterostichus spp – The genus name is a combination of the Greek words pteron meaning “wing” and stichon meaning “divided by lines”. This refers to the pattern of parallel grooves that extend along the thicken wings called elytra (Greek meaning “sheath”) that cover and protect the dorsal side of beetles. The abbreviated spp signifies species pluralis and is used to refer to a genus and all of its species. There are 150 species of Pterostichus in North America. [2]

Potpourri: While it may seem that there could be nothing more mundane than a common black ground beetle, they are an important capstone species as apex predators of the detritus-covered soil that serves as the font for almost anything that grows. They are ubiquitous, also implied by mundane, which can mean worldly in addition to commonplace. Beetles comprise the order Coleoptera, the largest order in Kingdom Animalia, and make up about a third of all insects. There are some 300,000 species of beetles globally of which about ten percent are indigenous to North America. Coleoptera is a direct Latin translation of the Greek koleooptera meaning “sheathed wings”.  The most distinctive features of beetles are the hard, rigid anterior wings called elytra that are not used for flight but sheath and protect the underlying delicate membranous flight wings. [3] Darwin is frequently credited with the observation that “The Creator would appear as endowed with a passion for stars, on the one hand, and for beetles on the other, for the simple reason that there are nearly 300,000 species of beetle known, and perhaps more, as compared with somewhat less than 9,000 species of birds and a little over 10,000 species of mammals.” The quote is properly attributed to the Neo-Darwinist J. B. S. Haldane. [4]

Beetles are prolific in part because they have carved out unique and surprisingly innovative niches in the tangled web of diverse ecosystems. They come in many shapes and sizes to suit the specifics of their subsistence profile. Tiger beetles are close cousins of ground beetles that chase down their prey at high speed over open ground. Tumblebug scarabs roll up balls of dung as hatcheries and first home for their progeny. Lady bird beetles are divinely benign (called cows of the Virgin Mary in France) for devouring aphids that suck plant fluids and destroy crops. Japanese beetles are an invasive blight to any gardener seeking to specialize in roses or fruit trees. Carrion beetles finish off the carcasses of anything too small or unpalatable to larger predators. Blister beetles exude toxins to protect their eggs from being eaten, named for its effects on the flesh of humans. Ground beetles are the generalists of the lot, living quiet lives under logs, rocks, and wet leaves of the forest. Turn over any log and you are likely to find one or more.

Ground beetles comprise the family Carabidae and are therefore also known as carab beetles or simply carabids. The family name is from the Greek word karabos, originally a type of crab which probably carried over to ground beetles due to the similarity of the hardened outer shell, which serves as an armored shield. Both crab and beetle shells are held together with chitin, an organic polymer that is also the main structural component of most fungi and many algae. Chitin is underappreciated as an important biological compound relative to cellulose, the primary structural component of plant cell walls. Both are polysaccharides, comprised of a string of many (poly) sugars (saccharides). The saccharide of choice for both chitin and cellulose is glucose, better known for its role as animal blood sugar, joined end to end with oxygen bonds. About one half of all carbon that comprises earth’s organic life, sometimes referred to as the biosphere, is cellulose. This amounts to one exagram (10 with 18 zeroes) of carbon that is processed and degraded annually, the mass of a mid-sized asteroid. Chitin differs from cellulose in structure only in having one side-bonded acetyl molecule and is only slightly less abundant as a carbon repository. [5]

Ground beetles also proliferate due to physiological attributes that promote adaptability. The most obvious design feature is the hardened, protective carapace they develop as adults, a property of all beetles. Box turtles live long lives due to the coevolution of a similar structure that wards off all but the most determined assaults. Beetles are attacked by fewer predators than other insects. [6] But there is more to beetles than an “intelligent” design. A study of the response of ground beetles to a combination of abiotic factors such as temperature and humidity and biotic factors such as competition and parasites revealed three distinct advantages: (1) Ground beetles are eurytopic, meaning that they can withstand a wide range of environmental conditions; (2) Ground beetles are adventurous rovers that seek out and colonize new areas; (3) Ground beetles are omnivorous and will consume anything edible. [7] But, as Michael Pollan points out in The Omnivore’s Dilemma, there is some danger in food selections due to toxins and a balance of different nutrients is required. Ground beetle experiments have demonstrated an innate selectivity that accounts for overall nutrition. Beetles fed a pretreatment diet lacking protein subsequently sought out protein-rich foods. A similar behavior was found with lipid or fat nutrient levels.[8]

Of the 3,000 plus carabids in North America, most are voracious predators, both as larvae and as adults. The family Carabidae is in the suborder Adephaga, which literally means glutenous in Greek.  With strong jaws for crushing, they are surprisingly fast and agile. The larvae even have two claws at the end of each of their six legs called urogomfi (literally tail-tooth in Greek) for grasping writhing prey. Ground beetle consumption is prodigious. They can eat over twice their body weight in a single day. In the beetle version of the classic movie Cool Hand Luke in which Paul Newman eats 50 hard-boiled eggs, this would equate to fifty repetitions or 2,500 eggs.  This gustatory act, which would seem to violate the laws of physiology and maybe physics as well is empowered in part by the manner in which food is consumed. Ground beetles regurgitate digestive fluids that partially decompose the crushed carcass to facilitate ingestion as a partially liquified meal, a behavior they share with spiders. And what do they eat? Basically, anything organic that is smaller than they are, which typically consists mainly of invertebrates such as worms, mollusks, and the larvae of other insects (including caterpillars and cockroaches). [9]     

Because of their ubiquity and dining habits, ground beetles are generally good for agriculture, the science (and art) of farming. This is because they consume many things that are bad for agriculture. Crop pests are more frequently remediated with pesticides. Since chemicals that kill tend to be toxic to other living things that cohabit the targeted areas, applying them can also adversely affect the ground beetle population. As a case in point, a field experiment was conducted in Britain to measure the effects of pesticides applied to rid cabbage patches of the maggots (larvae) of the cabbage root fly. The surprising result was that the cabbage fields to which the chemical was applied suffered more maggot damage than those unsprayed as control. Investigation revealed that over 30 species of beetle ate the eggs and larvae of the offending predator and that the pesticide reduced their number to the extent that more root flies survived. [10] Two of the laws proposed by Barry Commoner, the father of ecology, are “Nature knows best,” and “Everything is connected to everything else.” Ground beetles are proof positive, and studies of cultivation practices have been conducted to determine best practices. These have shown that deep tillage depletes ground beetle population whereas reduced tillage with organic fertilization and green manuring promotes them. [11]

Most ground beetles look alike. In fact, the photograph above may very well be a bessbug, a similar beetle that lives in the same rotting log habitat but does not compete with ground beetles since bessbugs consume decaying wood and are not predatory. Even entomologists that specialize in beetles have trouble telling them apart.  The obscure French entomologist René Jeannel (1879 – 1965) spent most of his life studying the speciation of nearly identical cave beetles. After a career of detailed research, he discovered that one of the most reliable identification tools to distinguish one beetle from another was the shape of the male reproductive organ called aedeagus from the Greek aidoia meaning genitals. This practice has continued to the present; it is a relatively common practice for biologists to use both male and female genitalia as a key indicator of species.

Beetle aedeagi generally consist of a capsule-shaped organ from which an inflatable sac extends like a windsock. The extended “penis” is studded with bristles and spines, which must have some purpose as beetles are bisexual and intercourse is de rigueur for procreation. The current hypotheses is that male beetle semen contains chemicals that influence female sexual behavior and that this effect is enhanced by being directly transferred to the blood via spine puncture wounds. Recent experiments employed a micro laser gun to remove some male penal spines to form a test group to compare with a fully-spined control group. The end result was that females impregnated with the fully spined group produced more offspring. The presence of spines on the male sexual appendage is not as outlandish as it sounds. Spines (made of keratin, like hair) are also found on many primates and rodents and there is evidence based on residual DNA that they were they were at some point present on Homo sapiens. [12] So beetles do matter after all.

Footnote: No article on beetles would be complete without reference to the origins of the name of the inimitable Beatles. John, Paul, and George started out as the Quarry Men without a drummer in Liverpool in the late 1950’s. As they gradually developed the sound for which they are so well known today, they decided they needed a more memorable stage name. John is quoted as saying that he was “just thinking about what a good name the Crickets (Buddy Holly’s band) would be for an English group when the idea of beetles came into my head”. He is also credited with changing the spelling to Beatles “to make is look more like beat music, just as a joke”. The original spelling was Beatals.  After a short experiment with Long John and the Silver Beatals, presumably to sound more like Buddy Holly and the Crickets with a literary flourish, Beatals became simply Beatles and the rest is history. [13]

References:

1. Webster’s Third New International Dictionary of the English Language, Unabridged, Merriam Webster Co, Philippines, 1971, p 197.

2. Marshall, S. Insects. Their Natural History and Diversity, Firefly Books, Buffalo New York, 2006, pp 258-259, 287.

3. Milne, L. and M. The National Audubon Society Field Guide to Insects and Spiders, Alfred A. Knopf, New York, 1980, pp 533-621.

4. Haldane, J.B.S. What is life? The Layman’s View of Nature, L. Drummond, London. 1949, p 258 (Verified on paper by Stephen Goranson at Duke University)

5. Voet, D. and J. Biochemistry, John Wiley and Sons, New York, 1990, pp 255-257.

6. Gressitt, J. L. “Coleoptera” Encyclopedia Britannica Micropedia, Volume 4 pp 828-837 William and Helen Benton, publisher, University of Chicago. 1974.

7. Thiele, H. “Carabid Beetles in Their Environments. A Study on Habitat Selection by Adaptations in Physiology and Behavior”. Science August 1978, Volume 201 Issue 4357.

8. Mayntz, D. et al “Nutrient-Specific Foraging in Invertebrate Predators” Science 7 January 2005, Volume 307 Number 5706

9. Goncalves, M. “Relationship Between Time and Beetles in Mata de Cocal” Review of Brazilian Meteorology, Volume 32, Number 4, October 2017.  https://www.scielo.br/j/rbmet/a/kJPLKtB3gLTdfTcMB9vM4Vd/?lang=pt

10. Nardi, J. Life in the Soil, University of Chicago Press, Chicago, Illinois, 2007, pp 136-138

11. Kromp, B. “Carabid beetles in sustainable agriculture: a review on pest control efficacy, cultivation impacts and enhancement” Agriculture, Ecosystems, and Environment, Volume 74, Issues 1-3, June 1999 pp 187-228 https://www.sciencedirect.com/science/article/abs/pii/S0167880999000377?via%3Dihub   

12. Schilthuizen, M. Nature’s Nether Regions, What the Sex Lives of Bugs, Birds, and Beasts Tell Us About Evolution, Biodiversity, and Ourselves. Penguin House, New York, 2014, pp 28-31, and pp 150-157.

13. Spitz, B. The Beatles, Little, Brown and Company, New York, 2005. pp 175, 181, 196.

Masting Behavior of Trees

Acorn mast from white oak trees occurs about every 5 years, evidence of variability

Common Name: Masting – The production of copious quantities of deciduous tree nuts in a single year followed by several years of minimal nut production. The phenomenon involves all nut trees, regardless of species, within a well-defined geographical region.

 Scientific Name:  Seed masting or Mast Seeding – A slightly more technical term to emphasize that the purpose of masting is to accentuate seed propagation to promote new tree growth.

Potpourri: Mast is a noun of Anglo-Saxon origin (mæst in the original Old English form using the ligature æ) that refers to the accumulation of various kinds of nuts on the forest floor that served as food for farm animals, particularly domesticated hogs. Pannage is a mostly arcane term for the pasturing of animals in the forest to take advantage of the mast, a practice that played a major role in the sociological development of rural life in Europe. As the swine population grew in concert with the human population, the pannage season had to be restricted, traditionally from the feast of Saint Michael (September 29) to the last day of November.  Pigs were brought to the New World with the earliest expeditions, notably that of Hernando De Soto in the southeast from 1539 to 1542, the progenitors of the razorback. Hogs became central to the salt pork and fatback cultures of the Appalachian and Ozark Mountains, the oak-chestnut forests providing the mast for their sustenance. [1]

The process by which trees produce mast is called masting. The curious thing about masting is that it is not a continuous process but rather is cyclic. Every three to five years a tree will produce prodigious quantities of nuts; in between the “masts,” it will produce almost none. The span of time between masts varies according to tree species and a host of other ecological and climate factors and can be as long as ten years. It is a matter of common experience that many kinds of trees exhibit this behavior at the same time over a large geographic area. This poses two conundrums: (1) Why do the trees regulate their nut production in a boom or bust manner?; and (2) How do they manage to coordinate the same cycle with other trees over a large area? Individual tree masting is called variability and the coordination among masting trees is called synchrony. [2]

Variability has had two hypothetical explanations: resource responsiveness and economy of scale.  The basic precept of resource responsiveness is that an individual tree will respond to the resources at its disposal. In a good year with plenty of rain and sunlight, a tree would have more resources with which to manufacture more nuts, which would subsequently be more likely to propagate in a moist, nutrient rich environment.  The primary resources of interest (rain and an adequacy of sunlight) are determined by prevailing weather conditions. Since weather patterns extend over an extended geographic area, resource tracking could also explain synchrony, as all the trees would be subject to the same cycle of resources.

Nature is not that simple, however. The fact is that variations in weather do not correlate with masting; moist and sunny weather does not produce a mast crop any more than dry and overcast weather prevents one. Weather is not cyclic; a wet year is not necessarily followed by a dry year. Masting is much more consistent in periodicity and result, cycles of high nut production occurring on a regular, periodic basis. However, there is one aspect of resource utilization by masting trees that does track with mast cycles, the resources expended by the tree. A significant resource investment (estimated to be about 10 percent of its total nutrients) must be made by a tree to produce the flowers that, when fertilized, produce the seed nuts. What this means is that trees grow slowly during mast years and more rapidly in non-mast years as the resources are shifted from reproduction to growth.   This suggests that masting is part of a complex evolutionary behavior pattern that must derive from an ecological stimulus – economy of scale variability.

The term economy of scale refers to the general precept that benefits will be magnified by the scale of the population size. Buying in bulk lots distinguishes wholesale from retail with the former gaining the economy of scale reduced costs of larger quantities.  There are two corollaries associated with the economy of scale theory for masting variability – predator satiation and pollination efficiency. In predator satiation, masting is stimulated by a tree’s adaptive strategy for survival in a world of nut-eating predators (notably squirrels). By producing a super-sized nut crop, the predators become satiated so that an adequate number of nuts will survive to succeed for propagation of the tree species.

The seven white oaks in my backyard so overwhelm the squirrel population with acorns in a mast year that they scamper about in confusion with too many nuts to eat or bury. A rough calculation based on extrapolation yields a total over 200,000 acorns. When squirrels cross from the back yard to the front past the side of the house, they are confronted with an equally overwhelming mass of hickory nuts from the hickory trees there, which, of course, mast in synchrony with the oak trees. The predator population is held in check during the non-mast years, when the parsimony of production is reflected in declining populations. In the economy of scale paradigm, each nut in a mast year has a greater probability of escaping predation.

Hickory nut mast 10 meters away from acorn mast above, evidence of synchrony

Pollination efficiency is based on the notion that it is more efficient from the resource standpoint for a plant to successfully propagate if there are a large number of sites for germination. This is not true for all plants. Flowering (Angiosperm) plants employ insect pollination, meting out nectar advertised by their attractive flowers to take advantage of male pollen transport to the female ovary of another plant. Chicory is a good example, as only a few flowers open each day and each expires at day’s end. Oak and hickory trees are monecious (male and female flowers are on the same tree) and their pollen is transported from staminate to pistillate flowers by the wind.  From the standpoint of reproductive success, it is advantageous for oaks to fill the air with pollen from many trees at the same time, saving up energy during off-years. Fungi are also mostly wind-pollinated and accordingly produce spores in prodigal proportions; a giant puffball is estimated to contain about 7 trillion spores.

Field testing for experimental evidence of predator satiation and pollination efficiency as causative factors for the masting behavior of trees is difficult and the results tenuous. For example, a study of masting trees in a 6-hectare study area estimated pollination efficiency by counting the total number male flowers and the number of nuts produced from1988 to 1993. Testing for predator satiation is even more difficult; one must not only show that predators were satiated but also that the interval between masting events was sufficient to result in a decrease in predator population. The same study utilized the number of nuts that had evidence of insect predation relative to those that were undamaged as a measure of satiation. The year-to-year variance in nuts with evidence of insect predation was used to determine the mast interval. The study concluded that both effects were observable, pollination efficiency having a greater impact than predator satiation. [3]

But the real conundrum is not why trees mast as individuals (variability), but how they coordinate their activities over large areas and across different species (synchrony). It is a matter of direct observation and scientific study that they do. A survey of acorn production was initiated in 1994 to quantify acorn production of blue oaks at 10 different sites at separated by up to 700 kilometers in California. The conclusion, after eleven years of study was that “acorn production extends to pretty much every blue oak, a population of 100 to 200 million individuals.” A more comprehensive literature survey of relevant references on nut production by various trees was organized by W.D. Koenig, a professor at UC Berkeley. A review of 72 sites and 5,000 data points revealed that synchronization of seed production was statistically significant in populations separated by 2500 kilometers. [4] One may conclude that synchrony occurs over long distances and involves almost every tree. So how do they do it?

Three mechanisms are germane to any discussion of synchronization of activities among plants or animals: chemical, reproductive, and environmental. The use of chemicals to transmit signals among individuals is common. However, it is not likely that this is pertinent to the case of masting as chemicals act over much shorter ranges than is observed in masting tree populations. Reproductive synchronization in arboreal terms is called pollen coupling. The concept is that if a tree depends on the pollen from a second tree to produce the fruit nut, then it must be synchronized with it. Implicit in this is that the tree that is providing the pollen must be at some relevant distance away. The effective distance over which pollen is effective in achieving fertilization is of value in forest management; recently completed studies have revealed that pollen is only effective within a range of about 60 meters, hardly on the order of the observed ranges of masting behavior. [5] A second reason that this mechanism is irrelevant here is that both oak and hickory trees are monecious, so the pollen doesn’t need to travel more than a few meters. Since it is not likely that chemical or reproductive effects result in the long-distance synchrony of masting, one must conclude that the only other reasonable choice would be environmental.

The notion that resource responsiveness to the environment causes the masting behavior of individual trees, i.e. variability, was ruled out above based on field observation. The question is how environmental resources that could not cause masting variability would nonetheless be the cause for masting synchrony.  It is the difference between weather and climate, the former term referring to the short-term manifestation of the latter. The idea that the environment can cause synchronous fluctuation in population size is not new. It is called the Moran effect after the Australian statistician who showed that the correlation of two populations at different locations was equal to the correlation in their common environmental influence (if they were subject to the same basic parameters).  It has been demonstrated empirically in many organisms, from viruses in the body to caribou in Greenland. [6]

It is therefore possible that geographically wide-ranging climate conditions cause trees to mast in synchrony. It is not known at present what aspect of the climate is predominate, if, in fact, it is that simple. There is some evidence that temperature may be a key parameter. The study of the California oaks was correlated with the mean temperature in April over the course of the eleven years of data. April was chosen as the most important month for masting, as it is when the trees produce the male and female flowers that result in nuts that ultimately fall as mast. The spatial synchronization of April temperatures was found to be even more strongly correlated than the masting of the oaks. The rationale is clear: the periodic fluctuations of temperatures (perhaps caused by the cyclic El Nino phenomenon) operate in synchronization with masting over the same geographic area. [7]

Or maybe it is something else altogether. The recent demonstration of the communion of all of the trees in the forest in concert with their mutualistic fungal partners may offer an alternative hypothesis. It is demonstrably true that the stronger trees in a forest send nutrients to the weaker trees in the forest and the trees in the sun send nutrients to the understory trees in the shade in order to keep the forest ecosystem in balance [8], then why wouldn’t these same signal paths send the signal to make more nuts? As the nutrient levels build up in the tree roots and fungal mycelia during high growth years, a crescendo point is reached and each and every tree gets a boost of energy to make it a mast year. This would certainly explain synchrony, and, given the vast dimensions of the “wood-wide web” it would also explain regional geographic expanse. All of the trees in the forest would benefit from an increased likelihood of the growth of saplings that would eventually succeed their parent trees so that the forest as “mega-organism” survived.

A similar and probably related observation is that many fungi will gather their resources for years only to erupt in a single year that results essentially in what might be considered a mast of mushrooms. There are many similarities as fungal spores, like the pollen of trees, benefit from a large cohort; each germinating spore creates a hypha that must find a mate. The fact that oaks have an especially large number of fungi with which they form mycorrhizal associations is quite likely why they are so successful as climax forest tree species in part due to the benefits of masting to longevity in a healthy forest. [9]

Another point to ponder at this juncture is why the masting phenomenon is restricted only to nut trees like oaks. What about the seed-bearing cones of conifers? It is not uncommon to traverse a pine forest, noting the soft tread of pine needles and a profusion of cones. The pine needles are indicative of a little noted characteristic of evergreens. They lose their needles just as deciduous trees shed their leaves. They just don’t do it all at once but take about four years to recycle all needles (longer for firs and spruces).  Cone masting is more of a challenge, however, because it takes three years to produce a cone. Year one requires moisture and sunlight to prime the cone by accumulating resources, year two must be dry to enhance pollination, and year three must be wet and sunny for cone growth. While cone trees “mast” based on field observation experience, there does not appear to be any synchrony between conifers masting cones and deciduous trees masting nuts. This has led to the hypothesis that cone bearing trees produce copious seeds when environmental conditions favor germination as opposed to the more social sharing behavior of nut trees.  [10]

Pine trees also produce many cones with their embedded pine nuts on a periodic basis like oak and hickory trees

Over the last twenty-five years, research to better understand tree masting and its effects of forest health has continued, expanding across the globe from its mostly North America and Europe roots and to involve specialists from fields other than botany. Of note is confirmation of the wide geographic range of masting synchrony that has been shown to be of intercontinental scale, extending to over thousands of kilometers. This suggests that fluctuating weather patterns driven by some environmental factor (the 11-year sunspot cycle has been proposed) must be key to synchrony as nothing else could be so widespread.  One of the more influential studies concluded that masting was the fundamental driver of animal behavior: “variable acorn crop size drives a chain reaction linking deer populations, ticks, and Lyme disease along with mouse populations, ground-nesting birds, and gypsy moths”.

The fundamental debate is now focused on the relative importance of resource matching (that masting depends on some limited resource), and economy of scale (that masting depends on genetic evolutionary trends of the tree species). A resource budget model has been proposed that unites the two with advantages of evolving to produce mountains of acorns weighed against the resources needed for synchronous reproduction. [11] The bottom line is that there is not (yet) an accepted comprehensive explanation for masting, despite its importance to the health of forests and the animals and fungi that live in them. It may well be that we are just at the threshold of understanding the real, complex nature of forests.

References:

1. DeVoto, B. The Course of Empire, The Easton Press, Norwalk, Connecticut, 1988. pp 23-31.

2. http://uslancaster.sc.edu/faculty/scarlett/acrnsmry.htm  

3. Shibata, M. et al “Causes and Consequences of Mast Seed Production of Four Co-occurring Carpinus species in Japan” Ecology, January 1998, pp 9 – 12 This paper documents a thorough field test of masting hypotheses.

4. Koenig, D. and Knops, J. “The Mystery of Masting in Trees” American Scientist Volume 93 July-August 2005. Pp 340-349.

5. Knapp, E. et al “Pollen-limited reproduction in blue oak: Implications for wind pollination for fragmented applications” Oecologia 128 March 2001 pp 48-55.

6. Moran, P. A. P. “The statistical analysis of the Canadian lynx cycle. II. Synchronization and meteorology” Australian Journal of Zoology, June 1953 pp. 291–298.

7. Koenig, D. and Knops, J. Op. cit.

8. Klein, T. et al “Belowground carbon trade among tall trees in a temperate forest.” Science 15 April 2016, Vol. 352, Issue 6283, pp. 342-344.

9. Binion, D. et al Macrofungi Associated with Oaks of Eastern North America, West Virginia University Press, Morgantown, WV, 2008.

10. Lauder, J.  “The Science of Masting: Why are there so many acorns (or cones)?” Sierra Streams Institute. 15 October 2024 https://sierrastreamsinstitute.org/2024/10/15/the-science-of-masting-why-are-there-so-many-acorns-or-cones/    

11. Koenig D. A Brief History of Masting Research Philosophical Transactions of the Royal Society, 26 March 2021 Volume 376

Porcelain-berry

The multi-colored somewhat translucent berries are reminiscent of porcelain

Common Name: Porcelain-berry, Amur peppervine, Blueberry climber, Porcelain berry vine – Porcelain is a hard and translucent ceramic made from kaolin (a type of clay) mixed with a variety of other minerals such as feldspar and quartz noted for its aesthetic properties. The multi-colored berries of this grape family vine are similarly attractive.

Scientific Name: Ampelopsis brevipedunculata – The genus is derived from ampel, the Greek word for grapevine. The species name means short (brevi in Latin) peduncle, the main stem that holds the flower that becomes the seed-bearing berry when fertilized. Formerly (and more frequently) listed as A. glandulosa and more recently as A. glandulosa var brevipedunculata.

Potpourri: While kudzu may be the vine that ate the South, porcelain-berry is well on its way to becoming the vine that ate New England. Both are invasive plants of the first order, combining supercharged seed reproduction and rapid vegetative growth of up to 15 feet in a single season. They are also both vines, employing the insidious and parasitic characteristic of using stems of other plants for support, the floral equivalent of spineless. Both plants were intentionally introduced to North America in the late 19th century mostly for their appearance. In the age of horticultural innocence that then prevailed, the only consideration for importation of alien plants was as an attractive addition to a garden. All went well for a time, until the mass movement of people from cities to suburbia with lawns and gardens after 1950. Porcelain-berry went with them, now in close proximity to natural fields and forests to which it soon spread unchecked. The exponential growth of invasives in the last twenty years does not augur well for the future of humanities’ continuing diaspora into exurbs and beyond. [1] In that garden plants are selected by horticulturalists for their hardiness and rapid growth, their emergence as invasive species when unintentionally released is no surprise.

The name Amur peppervine is apropos, as the plant is native to the Amur River basin that extends from Mongolia eastward through central China into the Strait of Tartary and ultimately the Pacific Ocean. It is also indigenous to Japan, India and parts of Southeast Asia having spread southward and eastward. [2] On its home turf, where porcelain-berry evolved in concert with a community of native and competing flora and predatory fauna, it is held in check. All that is gone with transplantation an ocean away in an equally fertile and climatically consistent locality like North America. In the absence of any of the constraints that drove its evolutionary characteristics in its homeland, some plants (and animals) can spread unchecked and outcompete native species.

Invasion of porcelain-berry

There are several factors that contribute to the success of porcelain-berry over the native flora of North America. Success may seem an ill-chosen description for a nuisance invasive, but proliferation and dominance are the evolutionary goal of every living thing. In late spring to early summer, an array of small, greenish-white flowers appear in flat-topped clusters called cymes that offer the promise of nectar to visiting pollinators. Porcelain-berry is monoecious, meaning that each plant has both male and female flowers, facilitating fertilization by roving pollinators, mostly bees. In early fall, the now fertilized flowers give rise to the reproductive berries, that start out white and gradually change to yellow, lilac, green, and turquoise. The attractive multi-colored berries that have been compared to miniature bird eggs are what drew the horticulturalists and their gardener clients in the first place, giving rise to the name porcelain-berry as a marketing moniker to evoke the comparable beauty of its namesake ceramic. [3] It is ironic that China is the fons et origo of porcelain, dating from the Han Dynasty of the first century CE. Porcelain was called china without attribution in the United States for many years. It is doubly ironic that Japanese stilt grass, called packing grass for its functional purpose, was the material used to protect the imported porcelain/china during transit whence it escaped into the wild as discarded shipping waste to become invasive, now joined by porcelain-berry.

The rainbow-hued berries afford an appealing visual palette that must be attractive to animals, mostly birds; humans are somewhat more sophisticated animals with similar aesthetic preferences. Since the fruits produced by most plants are nearly universal in having a single hue when ripe, it is relevant to consider not only how color variability is accomplished, but also why. It is well established that the reds and blues of fruits and flowers are due to the chemical anthocyanin, which literally means “blue flower” in Greek. It was named colored cell sap by the German botanist Ludwig Marquart in 1835 when he determined that it formed by the reaction between the sugar produced by the plant and proteins in the sap. [4] Most plants leave it there, the green chlorophyll-colored fruits infused with colored cell sap to turn them mostly red but sometimes blue. The color change indicates ripeness to roving animals to promote fruit consumption that spreads the seeds of propagation for the next generation. Amur peppervine creates a second chemical from the broad category of phytochemicals called flavonols that interact with anthocyanin to produce color variability. [5] This must be by design and not by chance.

Flower and fruit colors are evolutionary elements that result from a random mutation that proved effective in advancing the porcelain-berry genetic code. Accordingly, it is probable that the color-changing flavonol, once initiated, resulted in increased consumption, propagation, and germination of new generations with the multi-colored fruits. Eventually, these became dominant to the extent that all future generations carried the flavonol genetic code. Or, if one were to follow the logic of Michael Pollan in The Botany of Desire, it could be that the driving force was human aesthetics, spreading the seeds in order to fulfill a desire for berries of porcelain beauty. [6] Whatever effects different colors may have on attracting animals, the facility with which porcelain-berry seeds germinate and their multi-year viability also contributes to its spread. And even if there are no seeds, the plant spreads vegetatively and asexually by sprouting from its roots. [7] Taken together, the end result of seed and vegetative growth is a highly invasive plant that “is making a bold attempt to take over the world.” [8]

There is another good reason why the porcelain-berry was imported and widely planted without ecological concern or constraint. One of the key field identification features of porcelain-berry is that it has leaves that frequently look like those of the wild grape, although they can vary considerably, even on the same plant. This is because peppervine belongs to Viticeae, the grape family, cultivated since antiquity for fermentation as wine. When and where viniculture started is a matter of some conjecture, but the inclusion of Dionysus as the god of wine in Greek Mythology suggests a Paleolithic time frame. Recent research using DNA analysis of wine-stained chards from the Transcaucasian region provide evidence that modern wine making dates to at least 3,000 BCE. While 99 percent of modern wine is made from one of the many variants of Vitis vinifera var sylvestris, there are almost 1,000 species globally and it is almost certain that many other varieties were made into wine. [9] Therefore, most members of Homo sapiens that emerged in Africa about 50,000 BCE were familiar with some type of grape. The idiom I heard it through the grapevine has been around for awhile.

The unusual leaf shape of porcelain-berry is characteristic of Grape family plants.

Were it not for the alarming spread of porcelain-berry, it would be perceived as largely benign and even beneficial as are other grape family plants.  The porcelain-berry fruit can be safely eaten, providing some nutrition. However, it is not palatable, lacking the sugar content of cultivated grape varietals. In general, the two dozen species of wild grapes in North America, in which there is no reason not to include porcelain-berry, have edible fruits, shoots, and leaves. The average nutritional profile for 100 grams (~1/4 pound) of wild grape family fruits is 70 calories with several important minerals like potassium, calcium, phosphorous and iron and vitamins A and C in addition to the metabolically important B vitamins. [10] Similarly, wild grapes have a broad range of medicinal properties.  Native Americans used grape leaves made into a tea to treat stomachache and diarrhea and poulticed leaves were applied to treat rheumatism and headache. More recently, grape seed extracts have been shown to be effective in treating circulatory problems like varicose veins. [11] On the whole, it is reasonable to conclude that porcelain-berry is potentially a useful invasive.

References:

1. Young, J. National Research Council, Washington DC, “Fact Sheet, Porcelain-berry” National Park Service Plant Conservation Alliance Alian Plant Working Group, 20 May 2005, http://www.nps.gov/plants/alien

2. Zhiduan C. and Jun W. “Ampelopsis glandulosa (Wallich) Momiyama, Bull. Univ. Mus. Univ. Tokyo. 2: 78. 1971″, Flora of China online, vol. 12 p. 178-179.

3. Plants for a Future (PFAF) Charitable Database. “Porcelain Berry” https://pfaf.org/user/Plant.aspx?LatinName=Ampelopsis+brevipedunculata 

4. Hiker’s Notebook. “Autumn Leaf Color” at https://hikersnotebook.blog/2020/10/26/autumn-leaf-colors/

5. Nafici, S. “Weed of the Month, Porcelain Berry” Brooklyn Botanical Garden https://www.bbg.org/article/weed_of_the_month_porcelain_berry     

6. Pollan, M. The Botany of Desire, Random House, New York, 2001 pp. xiii-xxv.

7. Kling, A. “Invasions in your Woodland – Porcelain-berry” University of Maryland Extension. https://extension.umd.edu/resource/invasives-your-woodland-porcelain-berry-updated-2025/ 

8. Dingwell, S. “Unwanted and Unloved – Porcelain-berry” Virginia Native Plant Society. 12 August 2014.

9. McGovern, P. Ancient Wine, Princeton University Press, Princeton, New Jersey, 2003 pp 1-63.

10. Angier, B. Edible Wild Plants, Stackpole Books, Mechanicsburg, Pennsylvania, 2008, p. 80

11. Foster, S. and Duke, J., Medicinal Plants and Herbs, Houghton Mifflin Company, Boston, Massachusetts, 2000, p 338.

Bradford (Callery) Pear

A Bradford Pear tree on a ridge above the Shenandoah River probably escaped from a nearby development.

Common Name: Bradford pear, Callery pear, Braford Callery pear – The common name Bradford is eponymous, given to the tree to recognize the horticulturist who was the head of the USDA Plant Introduction Station in Glen Dale, Maryland where the cultivar of the Callery pear was first bred. Pear is from pirum, the Latin word for the fruit.

Scientific Name: Pyrus calleryana – The generic name is a variant of the Latin word for pear tree. The species name honors Joseph Callery (Giuseppe Calleri in his native Italian), a Catholic missionary to China who collected specimens of Asian native plants during his tenure there. He is recognized for having introduced the Callery pear to Europe in the 19th century.

Potpourri: Just as kudzu gained notoriety as the vine that ate the South, the Bradford pear is rapidly becoming the shrub that swallowed suburbia. As the Callery pear, it was originally imported from China in the early 20th century as an integral part of a United States Department of Agriculture (USDA) program to save the commercial pear industry from the devastation of a bacterial blight. The plan to use robust root stock resistant to blight from Callery pears grafted with the commercial, French pear was sound, as a similar method had been used in the late 19th century to resolve the “Great French Wine Blight” using American vine roots resistant to the American insect pest (a type of aphid) that caused it. [1] The French pear trees grafted to Chinese root stock flourished. Had it ended there, the monoculture stands of white petaled trees and shrubs that line many roads and dominate disturbed areas would never have occurred. The history of Bradford pear, like that of kudzu, is a cautionary tale of human intervention in ecosystems without a full understanding of the complexities of nature and evolution.

Before invasives demonstrated their ability to devastate native flora and fauna in the aughts of the 21st century, moving species randomly around the globe, sometimes purposely, was not only tolerated, but encouraged. Tomatoes, corn, and potatoes originated in the New World to become staples of European cuisine just as wheat, cotton and rice were imported and widely planted in the Americas. The genus and species scientific classification system of Carolinus Linnaeus still in use after over three hundred years was undertaken to organize the thousands of newly discovered plants submitted and named by field naturalists augmented by a list of descriptive nouns and adjectives, mostly in Latin. [2] The intentional importation of alien plants was mostly benign, with the exception of plants like dandelion, plantain, and garlic mustard that spread, crowding out the native species due to their superior resiliency. Bradford pears occupy a middle ground, having been introduced with good purpose, then intentionally hybridized to satisfy consumer demand for landscape trees. 

The story begins in the decades following the Civil War as Conestoga wagons forged ever westward to colonize the verdant valleys on the windward side of the Sierra Nevada. As herding gave way to agriculture in the late 19th century, the search for plants that would flourish there became the mission of the purposely established USDA Foreign Seed and Plant Introduction Office. Due to similarities in climate, east Asia was considered the best potential source for candidate botanicals. A stout-hearted  Dutch immigrant gardener cum naturalist named Frank Meyer with no fear of travel to remote areas to forage in relative isolation was recruited to undertake the mission. Like Darwin’s mission to collect specimens around the Pacific rim on HMS Beagle from 1841 to 1846, Meyer collected a wide variety of cereal grains, leguminous vegetables and fruits between 1905 and 1915 that eventually led to many of the food crops that have been cultivated in North America for over a century. Meyer’s initial forays did not seek out pears, as they were already well established in California,  Washington and Oregon. [3]

The genus Pyrus probably originated in the Tian Shen Mountains in the Xinjiang Province of western China. Pear trees hybridized as they spread throughout Eurasia as a natural progression by animals, especially birds, eating the much smaller fruit of wild pear trees and defecating its seeds. Cultivation of larger, sweeter pears preferred by Europeans predates historical records but probably started in Mesopotamia. The resultant European pear (P. communis) was brought to the colonies of the Americas by both the British and French from the east and the Spanish from the south giving rise to orchards as early as the 18th century. Pear groves proliferated, particularly in the Pacific Northwest to make pears the third most consumed fruit in the United States, trailing only apples and peaches. As with most commercially grown fruit trees, grafting is used to grow an appealing pear variant onto rootstock selected for its hardiness Since pear trees are therefore essentially identical clones―a genetic monoculture―they are subject to epidemics as a microbe that infests one will spread to them all. This is precisely what happened to the pear industry in the early 1900s. [4][5]

Meyer returned to the United States in 1916 to observe the effects of the fire blight caused by the bacterium Erwinia amylovora on pear orchards. Professor Frank Reimer of Oregon State University had initiated a program in 1912 to find a North American pear species that was resistant to the blight to no avail and enlisted the aid of Meyer to find an Asian pear species. When he returned to China in 1918, Meyer focused on Pyrus calleryana, noting in a communiqué to the USDA that the “form from the Yangtze Valley seems to be better suited for Oregon than the one from South China.” After trekking though China for some months to seek out the tree, he concluded in another letter that “Pyrus calleryana is simply a marvel. One finds it growing under all sorts of conditions; one time on dry, sterile mountain slopes; then again with its roots in standing water at the edge of a pond.”  In 1918, he proceeded to collect and ship 100 pounds of seeds back to the USDA for testing and began his journey home. He never made it, falling overboard to his death from a ship on the Yangtse River. His body was found thirty miles downriver on June 9, 1918. His colleague Reimer wrote “Mr. Meyer was one man in many thousands. He possessed a great brain and also a great heart.” [6] A suitable epitaph would be Frank Pearseed to stand beside John Chapman of Appleseed fame in the pantheon of American agronomy.

The showy spring florescence is one of the appeals of Bradford pear as a landscaping tree.

The seeds sent by Meyer were provided to USDA Plant Introduction Stations in Corvallis, Oregon and Glenn Dale, Maryland to assess the viability of P. calleryana as both root stock and as a new pear variant. The root stock proved to be resilient to the ravages of fire blight and was subsequently used to reestablish of pear orchards, saving the pear industry from devastation. Over three decades later, one of the Callery pear trees planted in Maryland caught the attention of a USDA employee named John Creech. Noting the glossiness of the leaves, the aesthetic, geometric balance of its spreading branches, and the lack of sharply spurred twigs that were typical of pear trees,  he concluded that it would make an exceptional landscaping tree. By grafting branches from the original tree onto rootstock of P. calleryana, he cloned a cultivar variant that he named the Bradford pear in honor of a horticulturist employed by the Glenn Dale facility. The landscaping tree was commercially released in 1962 and quickly became popular due to the attributes that drew Creech. According to a respected and seminal plant guide, “The Bradford pear, a selection of P. calleryana, has recently become popular as an ornamental because of its profuse spring flowers and red fall color.”  [7]

Bradford pear thicket along a road in Maryland

The Bradford pear became one of the primary trees lining the streets of American suburban sprawl built outward, a mecca from the noise and congestion of cities in the second half of 20th century. To satisfy the insatiable demand for variety in the cookie cutter sameness of burgeoning developments, twenty four variants of the Callery pear were introduced with catchy names ranging from Whitehouse to Autumn Blaze to augment the original Bradford cultivar. Like the ancestral Callery pears of China lauded by Meyer for their stamina and ubiquity, the Bradford pear and its variants were indomitable, thriving in poor soil that could be wet or dry, acidic or alkaline, resistant to disease, and reliably radiating branches of bouquets in spring and brilliant red fall foliage reminiscent of New England’s maples in autumn. Millions were planted across the country from California to Connecticut. [8] By 2015, Bradford pears had become the third most popular tree in New York City with a population of 58,000. The transition from desirable landscaping tree to pernicious pest occurred slowly, as the phalanxes of flowering white trees lining major roads could no longer be dismissed as part of a normal spring renaissance. [9]

What happened was hybridization. This was unexpected but could have been anticipated. Since Bradford pears and their ilk were clones in having been propagated by grafting small branches onto robust root stock (mostly P. calleryana), they were not able to cross pollinate and produce seeded fruits due to genetic incompatibility. However, the different horticultural cultivars were produced from pear seeds that were originally gathered by Meyer from all over China resulted in hybrids with different genotypes. This is the essence of the genetic diversity that Darwin first observed among the different specie of finches in the Galapagos Islands. As long as different hybrids are within individual bumble bee collection zones, chances are that eventually the pollen from a Bradford pear will find itself in the ovule of a receptive clone. The resultant fruit with its now mutant and fertile seeds, carried away for consumption by birds, especially European starlings and American robins, spread wherever and whenever the birds went, literally. Eventually, as a matter of evolutionary dynamics, a variant emerged that was super survivable. The Bradford/Callery pear has been listed as a “plant invader” by the US Fish and Wildlife Service in the mid Atlantic states since 2008. [10]


There is a certain amount of irony in introducing Callery pears to save the commercial pear industry from fire blight and then hybridizing it to create the hardy and aesthetic Bradford pear that has become a pernicious invasive. While other trees, like “tree of heaven” ailanthus and “empress tree” royal paulownia, have been introduced and become invasive, Bradford pears are unique in having been created by USDA plant breeders as a perceived public service. Contributing to the irony is that the fire blight bacterium that was the reason for the introduction of P. calleryana in the first place has reemerged as a major problem in the commercial pear industry due to its own evolutionary mutations. Walt Kelly’s Pogo cartoon for the first Earth Day provides the adage of the age: “We have met the enemy and he is us.” Barry Commoner, the father of ecology, proposed the law that “everything is connected to everything else,” a testimony to the complexities of the natural world. The only option at this point is to stop planting Bradford pears and their peers intentionally as landscape trees and to remove them whenever they spread into new habitats. There is evidence that the word is out. A sign posted at the trailhead at a Virginia State Park read “Wanted, Dead, not Alive, Callery Pear,” asking the public to “be on the lookout for this invasive intruder” and alert park staff so that it can be removed. The enemy strikes back.

References:

  1. Lukacs, P. Inventing Wine, A New History of one of the World’s Most Ancient Pleasures W. W. Norton and Company, New York, 2012, pp 169-174
  2. Wilson, C. and Loomis, W. Botany, 4th edition, Holt, Rinehart, and Winston, New York, 1967, pp 365-367.
  3. Culley, T. “The Rise and Fall of the Ornamental Callery Pear,” Arnoldia, Volume 74 Issue 3, 18 February 2017. https://arboretum.harvard.edu/stories/the-rise-and-fall-of-the-ornamental-callery-pear-tree/
  4. U.S. Department of Agriculture. “Pyrus Crop Germplasm Committee: Report and genetic vulnerability statement, September 2004” September 2004, Germ Resources Information Network (GRIN), pages 5-7
  5. Little, E. Field Guide to North American Trees, Alfred A. Knopf, New York, 1993, p 509
  6. Meyer, F. N. 1918. South China Explorations: Typescript, July 25, 1916–September 21, 1918. The National Agricultural Library. Available online at: https://archive.org/details/CAT10662165MeyerSouthChinaExplorations
  7. Brown, R. and Brown, M. Woody Plants of Maryland, University of Maryland, Port City Press, Baltimore, Maryland, 1999, p. 132.
  8. Higgins, A “Scientists thought they had created the perfect tree. But it became a nightmare” Seattle Times. 17 September 2018. https://www.seattletimes.com/nation-world/scientists-thought-they-had-created-the-perfect-tree-but-it-became-a-nightmare/
  9. McConnaughey, J. “Invasive Callery pear trees become a real menace” Washington Post, 17 May 2022

Cut-leaved Toothwort

The deeply lobed leaves are the most reliable feature for field identification.

Common Name: Cut-leaved toothwort, Pepperwort, Pepper-root, Spring blossom, Lady’s smock, Milkmaid, Large toothwort – The deeply indented leaves are an unmistakable key to the identification of this spring ephemeral. The root is a thick, white rhizome that is divided into segments having the appearance of a jawbone with teeth. Wort is from the Old English word wyrt meaning herb, plant, or root and is usually used in combination for an herbaceous plant. [1] It does convey a sense of medicinal use, as the word herb is sometimes construed.

Scientific Name: Cardamine concatenata – The genus name is from the Greek kardamine, a word meaning water cress. The species name is taken directly from the Latin concatenatus meaning linked together like a chain, recognizable in English as concatenate. This refers to the jointed “tooth” rhizome. Dentaria laciniata appears in many older texts with the genus having clear reference to teeth, the dent prefix in Latin. Laciniate means cut into deep and irregular lobes, also directly from Latin translation. The former scientific name translates to “tooth-like with deep lobes,”  the antithesis of cut-leaved toothwort. [2]

Potpourri: Spring ephemerals are the first harbingers of winter’s end and the start of the growing season powered by radiation from the sun and nurtured by water now unfrozen. The name is apropos, deriving from the Greek word ephemeros, lasting for one day. It is generally used for anything fleeting, including ideas, maladies, data, and especially cultural arts (out, out brief candle, life is but a walking shadow that struts and frets his hour upon the stage and then is heard no more).  Flowers that proliferate along the trail are the epitome of ephemeral in their brevity of growth, maturity of florescence, and the decay of death over the course of just a few days. In addition to the cut-leaved toothwort, the other notable ephemerals are bloodroot, hepatica, trout lily, spring beauty, and trilliums. As a trait shared among a number of unrelated species, ephemerality is the end result of a successful evolutionary response to environmental constraints that favors transience. Such traits are called convergent evolution as plants (and animals) converge to the same form and function independently.

The reason flowers trend toward the frenetic pace necessary to become ephemeral is neither recondite nor one of nature’s innumerable oddities. It results from the logical and successful strategy to take advantage of the short window of time during which there is little competition, other than from other ephemerals doing the same thing. Plants need the sun’s energy to make hydrocarbons and (most) flowering plants need pollinators to satisfy sexual needs (but not desires). Sunlight at ground level is abundant in early spring as the canopy trees have not yet foliated to absorb its energy for their own photosynthetic purpose (which is why trees grow ever upward in branches of leafy arrays). As insect pollinators first emerge in the cold blush of early spring in search of nutritive nectar, ephemeral flowers are abundant with showy blossoms offering the promise of a meal. There is little else to choose from.

Ephemerals make insect propagation easier by being generalists, meaning that any roving insect will do (many flowers – notably the orchids – are “designed” to attract a specific insect pollinator), and by being self-compatible, meaning that the pollen from the stamens in a flower will fertilize the ovaries in the pistil of the same flower. Bumblebees are the most adapted to pollinating ephemerals as they emerge early and feed abundantly to get a jump start on establishing a colony, a prodigious feat that must be completed by fall, a scant six months away. Their furry bodies shield them from cold and their continuous buzzing vibrations generate heat.  [3] While self-pollination is not a strategy conducive to long term survival in that it suppresses the genetic diversity of mixing genes, the raison d’être for sexuality, it suffices for ephemerals. Most plants reproduce by combining self pollination with sexual cross pollination to promote propagation with enough diversity to prevent extinction. [4] Whatever the mechanism, the evolutionary success of ephemerals is undeniable, as they are ubiquitous along forested pathways in the springtime to the extent that they define it as a time of resurgent life.

Cut-leaved toothworts employ a supplemental growth feature in the form of a root structure called a rhizome that extends horizontally from each plant to enable vegetative growth. The name toothwort is due to the resemblance of the rhizome to a jawbone with bumps that suggest teeth along its length. The bumps-cum-teeth are the origination points for individual flower stems that grew upward over the course of previous spring emergence. [5] This is a feature of a perennial plant, taking advantage of a well established root structure from which to grow and spread. While the four-petaled white to pink flower is what attracts ambling hikers for its beauty and itinerant insects for its pollen and nectar, it is the root for which it is named that  establishes a niche in the ethnobotanical catalogues as both a food and as a medicinal. While cut-leaved toothwort flowers each produce about ten seeds, amounting to as many as 100 seeds per plant, their fertilization and growth is infrequent, relying mostly on the anastomosis of spreading rhizomes for extension into new frontiers. [6]

The rhizome or root has the appearance of a jawbone with emergent teeth.

The most obvious, if least effective, human use of tooth-like roots was as a treatment for toothache and related oral maladies. [7] Prior to the modern era, disease was more fearsome as there was little knowledge of cause and remedies amounted to patent quackery like blood-letting and bat wing potions. In Western civilization, Christianity offered the only solace against the scourges of nature and a loving God was thought to have intervened to help believers survive (and prosper and, of course, propagate the faith and faithful). This was the origin of The Doctrine of Signatures in the 17th century, a theory that God left his mark/signature on plants to signify their use. It was only necessary to determine the divine purpose through enlightened human inspection. Heal-all would soothe sore throats because it looked like an open mouth and sassafras cured syphilis because the leaves are shaped like a penis (stretching credulity). [8] The use of a plant that had roots that looked like teeth was much more obvious. It could only have had an ameliorative placebo effect among the early colonists, many of whom came to the alien shores of North America aided and abetted by their profound faith.

The Native Americans knew better, having survived for thousands of years by applying the tried and true practices of trial and error to develop an herbal pharmacopeia passed down through generations by word of mouth. They did not use toothwort for toothache. But they used it for many other purposes ranging from aphrodisiac to food. The six tribes of the Iroquois Confederation of the Northeast are treated as a singular group even as their cultural traditions are diverse as reflected in their toothwort use. It was used not only as a medicine to treat specific conditions like headache and heart palpitations but as a kind of panacea to treat any injury, known as “little water medicine.” More imaginatively, the toothwort plant was rubbed over things like traps and fishing lines as a “hunting medicine.” The root was placed inside the mouth which produced an aura thought to attract the opposite sex as a “love medicine.” There is no evidence that any of these treatments were effective in improving love, hunting, or health.    

The one use of cut-leaved toothwort that transcends Native American practices and colonist adaptation to the current era is as wild food. The different applications imply some significant diversity in American Indian cuisine. The Cherokee of the Carolinas cooked the plant and roots with other greens as a vegetable medley. Further west, the Ojibwa made something of a stew with potatoes, deer meat, and corn flavored with the peppery taste of the roots. [9] The pungency of phytochemicals is one of the characteristics of the Mustard Family (Brassicaceae or Cruciferae) to which toothwort belongs. According to current tastes, the pungent roots can be added to a sandwich or to a salad for piquancy with a specific recipe to “scrape or grate several of these sharply flavored root stocks, mix with vinegar, and set on the table in a little covered pot.” [10] However, harvesting ephemeral flowers to eat their roots is neither an appropriate nor necessary way to interact with the natural world. Better to admire them as you walk through the woods in spring.

References: 

1. Webster’s Third New International Dictionary of the English Language, Unabridged. Encyclopedia Brittanica, Inc. Helen Benton Publisher Chicago, Illinois, 1971, p. 2637.

2. Simpson, D. Cassell’s Latin Dictionary, Wiley Publishing, New York 1968, pp 179,333.

3. Kricher, J. and Morrison, G. A Field Guide to Eastern Forests, Houghton Mifflin, Boston, 1988, pp.163-169.

4. Wilson, C. and Loomis, W. Botany, 4th Edition, Holt, Rinehart and Winston, New York, pp 347-362.

5. Niering, W. and Olmstead, N. National Audubon Society Field Guide to North American Wildflowers, Alfred A. Knopf, New York, 1998, pp 428-429.

6. Mahr, S. University of Wisconsin – Madison Horticultural Extension https://hort.extension.wisc.edu/articles/cutleaf-toothwort-cardamine-concatenata/ 

7. Foster, S and Duke, A. Medicinal Plants and Herbs of Eastern and Central North America, Houghton Mifflin, Boston, 2000, pp 38-39.

8. Needham, W. The Compleat Ambler, Outskirts Press, Denver, Colorado, 2020, pp 28-30.

9. Native American Ethnobotany Database. http://naeb.brit.org/uses/search/?string=toothwort

10. Angier, B, Field Guide to Edible Wild Plants, 2nd edition, Stackpole Books, Mechanicsburg, Pennsylvania, 2008, pp 234-235.

Raspberry

Black raspberries turn from red to black when fully ripe

Common Name: Raspberry, Black raspberry (photo above. Note that black raspberries are initially red), Blackcap, Thimbleberry, Framboisier noir (Quebec) – The etymology of raspberry is uncertain. One hypothesis is that it is simply a combination of rasp in the sense of being rough or harsh from French rasper, to scrape together. An alternative origin is from raspis, a sweet red wine popular in Europe in the Middle Ages. Berry is from beri, a Germanic word for grape. The red raspberry is also known as European red raspberry.

Scientific Name: Rubus occidentalis (black raspberry) and Rubus idaeus (red raspberry) –  Rubus is Latin for bramble-bush and, by extension, blackberry. The species occidentalis is from the Latin occidens meaning to go down or set, generally used to refer to the western hemisphere. The Black raspberry is indigenous to eastern North America where it was first classified. The species idaeus refers to Mount Ida in Asia Minor, where red raspberries originated.

Potpourri: The ubiquitous raspberry was indisputably one of the first plants to be recognized as a source of food for many animals, especially the naked apes that eventually evolved to Homo sapiens about 60,000 years ago. The prominently colorful berries, raspberry red in Eurasia where they originated, stood out from the verdant foliage, a distinction unseen by other mammals lacking the red vision of primates. Raspberries were almost certainly spread globally by migrating birds where new species arose as a result of evolutionary diverse habitats. In its current bramble form, raspberries resist consumption of its growing plant parts with conspicuous thorny outgrowths characteristic of its Rose Family taxonomy. Growing in dense thickets from root extensions called rhizomes, brambles like raspberry produce copious quantities of enticing berries to perpetuate its dominance in open, sunny areas. Black raspberries form impenetrable hedges along many trails, offering a succulent snack and an occasional prick to passing hikers.

Raspberries are aggregate fruits with prickles

Raspberries are not berries and they do not have thorns. The fruit is an aggregate, and the sharp-pointed protuberance is a prickle. The use of berry for any small, roundish fruit is as fraught in common parlance as the distinction between fruits and vegetables. A fruit is “a ripened ovary and its contents together with any adjacent parts that may be fused to it.” Fruits are the seed carriers of propagation. Grains like barley, vegetables like peas, and nuts like acorns are fruits. A fruit “in which the entire ovary ripens into a fleshy, often juicy and edible” is the botanist’s berry, inclusive of tomatoes, eggplant, red peppers, and watermelons. A drupe is different, having a layered ovary that gives rise to a central stone or pit that encloses the seed, like plums and peaches. Raspberries arise from flowers with multiple pistils (central organ of a flower), each producing a small drupe, sometimes called a drupelet. The multiple small fruits cling together, separating as a single unit that is called an aggregate. Rasp-aggregate would be a more correct name, but hardly useful.  Spines, thorns, and prickles are all sharp-pointed outgrowths from a plant surface that evolved to repel herbivores. Spines like those on barberries originated from leaves. Thorns like those on Osage orange arose from branches. Prickles like those on raspberries are the real stickers, emerging directly from stem tissues. [1]

Raspberries are classified as members of Rosaceae, the family of roses in the genus Rubus, known colloquially as brambles. With about 3,000 species, the rose family is not that large compared to the 20,000 species of the orchid family and 19,000 species of the composite family, inclusive of asters, daisies, and sunflowers. [2] However, the rose family is arguably the most renowned of all plant families from the human perspective. Its prominent floral and fruit products that proliferate the temperate zones of primary habitation are without equal in the kingdom Plantae. In addition to the many cultivars of roses that dominate the floral trade, they are the sine qua non for spectacles like the annual Pasadena parade and namesake bowl game and Kentucky’s running of the roses in the first of the three horseracing crowns. English wars have been named for them. The red rose Lancasters and white rose Yorks have nothing to do with the Lannisters and Starks even though they were both involved in throne games of a sort.  However, the fruits of the rose family that dominate at the supermarket are its most enduring legacy. Life would be lessened absent apples, pears, cherries, plums, and the various bramble berries. The success of the rose family is a result of the evolution of a number of traits that promote reproduction and dispersion. Having a diversity of fruits with the color, shape, and taste that appeal to birds and mammals results in spreading seeds far and wide in a dollop of fertilizer. More important, however, is asexual reproduction called apomixis by which rose plants can spread without pollinators. This is especially true of the brambles like raspberry that extend by horizonal, leafless stem structures called rhizomes. [3]

Rose family fruits in general and raspberries in particular have spread far and wide, part of Darwin’s “endless forms most beautiful and most wonderful” due to hybridization that results from a combination of seed dispersion and asexual apomixis. Apples abound in variety and raspberries are not far behind. There were already 41 varieties of raspberry in the United States in 1866. [4] Both apples and raspberries tend toward polyploidy, having multiples of the basic number of chromosomes, which can result in the reestablishment of sexuality to create new hybrids. This is further complicated with raspberries, that can have one of three different basic chromosome numbers (7, 8, or 9) to start with. This means that from their inception in Asia Minor, raspberries have spread across the globe in many hybrid forms, drawing the attention of the hominids doing the same thing. That they were well known by the time of the Roman Empire is well established. Pliny the Elder (aka Gaius Plinius Secundus), the noted Roman military leader and naturalist author, wrote in his magnum opus Naturalis Historia that the raspberry was “known to the Greeks as the Idæan bramble, from the place where it grows.”  Mount Ida is in Northwestern Turkey near the site of Troy, providing the species name idaeus of red raspberry. It was even then regarded as a medicinal plant, for Pliny notes that: “Its flower, mixed with honey, is employed as an ointment for sore eyes and erysipelas, and an infusion of it in water is used for diseases of the stomach.” [5] As raspberry seeds have been found at Roman forts on the British Isles, it is considered likely that the Romans spread the raspberry from its Asian origins throughout their vast empire into Europe and Africa. [6]

Raspberries have served as a wellspring for both nutritious food and medicinal remedy for the millennial span of western civilization. They found their way into the various herbal collections that appeared in Europe in the late 16th century. John Gerard, calling it the Raspis, Hinde-berry, or Framboise (French), notes that “the floures (sic), the leaves, and the unripe fruit, being chewed, stay all manner of bleedings. They heal the eies (sic) that hang out.” The ripe fruit is described as sweet, and “not unpleasant to be eaten,” [7] As the modern era erupted from the rediscovery of Greco-Roman writings in the Renaissance, the expansion of raspberries as one of the first fruits followed. By the 17th century, white and red cultivar raspberries were recognized in Great Britain that differed only in the color and taste of the fruit, the “white raspis a little more pleasant than the red.” Red wines were available at the “vintners made from the berries of Raspis that grow in colder countries.” The medicinal uses had also expanded, extending to the use of leaves “in gargles and other decoctions that are cooling and drying, but not fully to that effect” whatever that means. A syrup made from the berries “is effectual to cool a hot stomach, helping to refresh and quicken up those that are overcome with faintness.” And of course the berries were eaten “to please the taste of the sick as well as the sound.” [8] As the consumer era took off in the middle of the last century, the raspberry became a mass market food and one of the myriad herbal remedies to assuage modern melancholia.  

 Raspberries are nutritious, contributing to a healthy diet. They are one of the highest sources of dietary fiber (6.5 grams fiber per 100 grams wright) relative to the energy provided (100 kilocalories per 12.5 grams). In addition, they are high in vitamins C and K and in the minerals calcium, magnesium, potassium, and iron. Raspberries also contain a unique set of phytochemicals, secondary substances not involved in plant metabolism, that are likely the basis for the many historic folk medicinal uses. Anthocyanins, which are what make berries (and fall leaves) red, are noted for their antioxidant and anti-inflammatory activity, deactivating the free radicals (ionic forms) that tend to disrupt cellular activity. In vivo animal studies have found that consuming raspberries resulted in “reduced blood pressure, improved lipid profiles, decreased atherosclerotic development, improved vascular function, stabilization of uncontrolled diabetic symptoms (e.g., glycemia), and improved functional recovery in brain injury models”. [9] It may be concluded that the use of raspberries in the treatment of a variety of ailments has at least some rational basis due to actual chemical interactions operating above and beyond the placebo effect.

Native American herbal remedies provide one of the best examples of genuine folk medicine unadulterated by marketing hucksterism. The Iroquois Confederacy of the northeast had many uses for raspberry leaves and roots, including treating bloody diarrhea, as an emetic, to remove bile, to treat children with whooping cough, and, perhaps with some hyperbole, as a  “decoction taken by a hunter and his wife to prevent her from fooling around.”  Raspberries were also important as food, especially in winter when dried fruits were combined with hominy. Further south, Cherokee also used raspberry plants for digestive problems and as food but in the form of pies and jellies suitable for the milder climate. On the more practical side, the prickly stems were used for scratching itchy hard to reach places. In addition, it was used for coughs, boils, and, most significantly to current usage,  to treat postpartum pain. [10] Current usage as an herbal remedy follows those of Native American usage, with an emphasis on pregnancy issues.

The most prevalent use of raspberry over the last century has been during the last trimester of pregnancy to “relax the uterine muscles and facilitate birth.” [11] However, in Germany this is proscribed “because of lack of scientific support of claimed activities as a uterine tonic.” [12] The widespread use of raspberry leaves in herbal preparations for pregnancies has resulted in some serious scientific assessment. Approximately 50 percent of all pregnant women use some form of herbal treatments during pregnancy and the use of raspberry extracts as tea, tablets, or tincture ranges from 7 to 56 percent depending on the country. The claim made by the herbal industry is a “positive effect on childbirth through the induction of uterine contractions, acceleration of the cervical ripening, and shortening of childbirth.” No studies clearly demonstrate that products derived from raspberries have a clear effect on the biochemical pathways of pregnancy. A recent review concludes that “the consumption of raspberry extracts could translate into decreased dynamics, or even the inhibition of the cervical ripening process, which could undoubtedly translate into a more tumultuous and traumatic childbirth course.” It is increasingly clear in the medical community that the best way to stay healthy is to eat a balanced diet, exercise regularly, and avoid stress. Hiking along trails in the quiet of the forest and eating raspberries is a good place to start.

References:

1. Wilson, C. and Looms, W. Botany, 4th Edition, Holt, Rinehart and Winston, New York, 1967, pp 30-31, 285-304.

2. Niering, W. and Olmstead, N. National Audubon Society Field Guide to North American Wildflowers. Alfred A. Knopf, New York, 1998, p.354, 646, 746.

3. Cowan, R. “Rosales” Encyclopedia Britannica Macropedia, William and Helen Benton, Publishers, Chicago, 1972 Volume 15, pp 1150-1154.

4. Stuart, M. ed The Encyclopedia of Herbs and Herbalism, MacDonald and Company Publishers, London, 1987, p 255.

5. Pliny the Elder,  The Natural History – John Bostock, M.D., F.R.S. H.T. Riley, Esq., B.A. London. Taylor and Francis, Red Lion Court, Fleet Street. 1855. Book 16 Chapter 71 – https://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1999.02.0137:book=16:chapter=71&highlight=raspberry    

6. Burton-Freeman, B. et al “Red Raspberries and Their Bioactive Polyphenols: Cardiometabolic and Neuronal Health Links” Advanced Nutrition, Volume 7, Number 1 January 2016 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4717884/

7. Gerard, J. Herball – Or, Generall Historie of Plantes, John Norton, London, 1597. Pp 260-261

8. Parkinson, J. Paradisi in Sole, Paradisus Terrestris  1629. Reprinted by Methuen &Company, London, 1904, p 557 -558  https://www.gutenberg.org/files/69425/69425-h/69425-h.htm#Page_557 

9. Burton-Freeman et al, op. cit.

10. Native American Ethnobotany Data Base. http://naeb.brit.org/  

11, Polunin, M. and Robbins, C. The Natural Pharmacy, Collier Books, New York, 1992, p 122.

12. Foster, S. and Duke, J. Medicinal Plants and Herbs, Petterson Field Guide Series, Houghton Mifflin Company, New York, 2000, pp 264-265

13. Socha, M. et al “Raspberry Leaves and Extracts-Molecular Mechanism of Action and Its Effectiveness on Human Cervical Ripening and the Induction of Labor” Nutrients, Volume 15 Number 14, 19 July 2023. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10383074/

Horsenettle

Horsenettle flowers range from light purple to white, all with tubular yellow stamens to attract pollinators

Common Name:  Horsenettle, Bull nettle, Carolina horse nettle, Apple of Sodom, Devil’s potato, Thorn apple, Wild tomato, Poisonous potato – A nettle is a plant of the genus Urtica noted for stinging hairs. The name has been widely applied to other plants that have prickles like the horsenettle. The horse association is likely due to the fact that horsenettle plants are commonly found in pastures, like those fenced off for horses.

Scientific Name: Solanum carolinense – Solanum is Latin for nightshade. The genus name is attributed to Pliny the Elder (Gaius Plinius Secundus), a Roman military commander and naturalist in the first century AD. The origins of Solanum are unclear, but sol is Latin for sun; there is a sunberry flower in the nightshade family. The similarity in spelling to the Latin word solamen which means comfort is another possible etymology. [1] Plants of the Solanum genus have historically been widely used as medicine for a variety of ailments and conditions.  The species name is reference to the North American colony Carolina where it was first noted, probably before its division between north and south.

Potpourri: The horsenettle is a weed according to the standard definition as it grows where humans don’t want it to grow and crowds out preferred plants. If weediness is a matter of garden aesthetics, however, an argument can be made that the five-petalled white or purplish star with five yellow elongated stamens projecting from the center has some appeal. If weediness is detrimental to food crops like soybeans and wheat awaiting harvest from farm fields, then eradication with herbicides may be justified. Horsenettle is also poisonous to the extent that it is included in edible wild plant field guides as a cautionary measure to prevent gathering the wrong things when edible plants are sought. [2] But it is also medicinal, having been used by Native Americans and subsequently by colonizing Europeans for centuries. This, too, is not unusual, as horsenettle is a member of the Nightshade family, a rogue’s gallery of deadly plants that also includes potatoes, tomatoes, peppers, and eggplants, mainstay edibles of western cuisines. Horsenettle is bad weed, good medicine, and has ugly prickles.

Another thing that can be said about weeds like horsenettle is that they are successful plants, able to flourish in marginal soils and spread outward in profusion. That is what all living things aspire to do, perpetuating their own kind following the recipe for survival by being fittest. Darwin came to recognize that competition among plants was equal to if not more than that among animals, even as Galapagos finch beaks became his focus. As a backyard scientist with inimitable curiosity, he conducted an field test in his backyard by clearing six square feet down to bare soil to observe the emergence of native weeds. He noted that “out of 357 no less than 295 were destroyed, chiefly by slugs and insects,” the detail testimony to thoroughness. As confirmation, he repeated the experiment on a second area of established turf, noting that “out of twenty species … nine species perished” because the “more vigorous plants gradually kill the less vigorous.” [3] It is evident that becoming a successful weed is an evolutionary feat rather than a routine event. It is also apparent that the weeds that persist and become human problems are the cream of the weed crop, exceptionally evolved with propagative efficiency.

Horsenettles are poisonous because they produce an alkaloid chemical named solanine, the name derived from Solanaceae, the Nightshade family of almost 4,000 plant species in nearly 100 genera. Alkaloids are complex organic chemical compounds that can in many cases have physiological effects on animals ranging from medicinal like morphine, hallucinogenic like mescaline, and stimulants like nicotine (the “ine” suffix is prescribed). The root alkali is derived from the Arabic word for the calcined ashes of the saltwort plant, and refers to molecules that are basic (pH > 7), the opposite of acidic. Alkaloids are mostly bitter, which is undoubtedly the reason why bitter is one of the five tastebud types also including sweet for sugars, salt for minerals, sour for ripeness, and savory for proteins. Bitterness warns of  poison and most animals avoid bitter plants like horsenettle. The genetic code for bitterness taste sensors was retained by the survivors; individuals that lacked sensitivity learned about bitter poisons the hard way. Up until the nineteenth century, plant compounds were only known through trial and error. The alkaloid associated with the poison hemlock (coniine) was the first to be synthesized in 1886. [4]

The taxonomy of plants is based on familial similarities. The production of a specific alkaloid is typically a shared characteristic. This is true of the nightshades (Solanaceae) just as it is of buttercups (Ranunculaceae), poppies (Papaveraceae) and barberries (Berberidaceae). Alkaloid concentrations vary among the different species of a plant from plentiful to nearly nonexistent. The nightshades range from almost no alkaloid in tomatoes, potatoes, and eggplant to substantial amounts in horsenettle and tobacco. Why plants produce alkaloids is uncertain. Experiments have shown that tomatoes grafted onto tobacco stems produce no solanine.  Conversely, tobacco grafted onto tomato stocks does. This would indicate that solanine isn’t involved in growth or metabolism. However, that is not to say that there is not a purpose for a plant to make a complex chemical compound, which takes energy and raw materials. There is more to life than growth and there is more to genetics than the here and now. Alkaloids may be vestigial remnants that once had a purpose in the evolutionary past but which is no longer relevant.

Horsenettle fruits look like small tomatoes

Alkaloids may also have a role in reproduction, as some plants produce high levels during seed and fruit formation which become depleted when the seed is ripe. Horsenettle fruits look like miniature tomatoes. Whether they are toxic or not is an open question. One source says “the berries are the most toxic when they are mature” [5] and another says “all parts of the plants, except the mature fruit, are capable of poisoning livestock” [6] Since poisoning experiments on humans and livestock are not ethically acceptable, almost all reports of poisoning are anecdotal. It is probable that immature fruits are poisonous and mature, ripe fruits are not. This makes sense, as plants produce fruit to be eaten by animals so that the seeds are distributed in a dollop of fertilizing manure. For example, all parts of the mayapple are poisonous except the ripe fruit. Experiments with livestock that consumed ripe horsenettle fruits have shown that the seeds pass through the gut unharmed, exactly as would be intended and predicted. [7]

The relationships between animals and plants are complex. This is particularly true when it comes to alkaloids. Ostensibly, plants produce the bitter compounds through random genetic mutation and eventually a formulation occurs that keeps animal predation in check. However, in the niche-centric ecology of survival, the opposite must also occur. That is, animals that evolve some form of immunity to certain alkaloids in certain plants gain the advantage of abundant food avoided by competitive herbivores. The example of the monarch butterfly caterpillars eating milkweed that is poisonous to nearly all other animals is well known. Experimentation has shown that this is more the rule than the exception. When the Panama Canal was built in the early twentieth century, the flooding of Gatun lake created Barro Colorado Island where a Smithsonian Field Station was opened in 1924 to conduct long term experiments of evolution in an isolated biosphere. A recent study of the 174 caterpillars found on the island found that they were “picky eaters” is choosing which types of over 200 toxic compounds they would consume. This “encourages diversification, as new species with new, temporarily insect-proof toxin profiles emerge.” [8] It is not therefore surprising that a fair number of insects, and some animals, eat horsenettle leaves, stems, and fruit.

The vast majority of twenty first century humans have plenty to eat―in many cases too much. There is no cornucopia in the wild where life is “nasty, brutish, and short” according to Thomas Hobbes. Many insects and a few animals consume not only the horsenettle fruit, but also the bitter, normally poisonous leaves and stems as well.  A study conducted in Virginia over a period of six years (1996-2002) revealed that 31 insects from six different orders ate horsenettle voraciously. In fact, a detailed survey of 960 horsenettle plants found that the plants were severely damaged. And it wasn’t just bugs, as meadow voles also consumed horsenettle with no apparent ill effects. The most damaging insect species were those that also fed on other Nightshade family plants including the eggplant flea beetle and the false potato beetle in keeping with the evolutionary pathway of alkaloid tolerance.  Fruits were assessed separately due to their importance in propagation as the seed bearing component of the plant. The three species accounted for 75 percent of fruit damage were false potato beetles, pepper maggots, and meadow voles. [9] This also provides some validity to the overall scheme of life with plants producing sweet, tasty fruit to attract animals for seed dissemination.  

As is the case with many plants that are listed as poisonous to animals in general and humans in particular, horsenettle has historically been used for medicinal purpose. In the eons that preceded the Renaissance in the arts and sciences, treatment of human and livestock ailments was a matter of local lore and tradition using naturally occurring substances, mostly plants. Essentially, the chemicals created by a plant for its own use and protection provided similar benefits when consumed by an animal. In the case of horsenettle, the Cherokee who were indigenous to Virginia and the Carolinas where it originated were its most inventive purveyors. The leaves were used internally to dispel worms (apparently worms don’t like it either) and externally to treat poison ivy (although one would think that Cherokee had figured out the “leaves of three let it be” rule). Fruits were boiled in grease to treat dogs with mange and the seeds of the fruit were made into a sore throat gargle. [10] The Native American uses of native plants were in many cases adopted by early colonists so that these “natural remedies” appeared in the early listings of drugs. Horsenettle was listed in the United States Pharmacopeia  from 1916 to 1936 as a treatment for epilepsy, and, in keeping with the “snake oil” practices of unregulated past, both an aphrodisiac and a diuretic. It has long since disappeared from the apothecaries shelves, and is now mostly known for its toxicity. A modern medicinal plant guide concludes with “fatalities reported in children from eating berries.” [11]

References:

1. Simpson, D. Cassell’s Latin Dictionary, Wiley Publishing New York, 1968, pp 560, 772.

2.  Elias T. and Dykeman, P. Edible Wild Plants, Sterling Publication Co. New York, 1990, p 265.

3. Darwin, C. On the Origin of Species, Easton Press, Norwalk, Connecticut, 1976, p.50.

4. Manske, R, “Alkaloids” Encyclopedia Britannica, Micropedia, William Benton Publisher University of Chicago, 1974, Volume 1 pp 595-608.

5. North Carolina State University Agricultural Extension https://plants.ces.ncsu.edu/plants/solanum-carolinense/   

6. Bradley, K. and Hagood, E.  “ Identification and Control of Horsenettle (Solanum carolinense) in Virginia” http://www.ppws.vt.edu/scott/weed_id/horsenettle.PDF           

7.  https://www.illinoiswildflowers.info/prairie/plantx/hrs_nettlex.htm

8. “One hundred years of plenitude” The Economist, Science and Technology, 6 July 2024. p 64.

9. Wise, M. “The Herbivores of Solanum carolinense (Horsenettle) in Northern Virginia: Natural History and Damage Assessment” Southeastern Naturalist,  1  September 2007,  Volume 6,  Number 3, pp 505-522.

10. Native American Ethnobotany Data Base http://naeb.brit.org/  

11. Duke, J. and Foster, F. Medicinal Plants and Herbs, Peterson Field Guide Series 2nd edition, Houghton Mifflin Company, Boston, 2000, p 206.

Spotted Lanternfly

The adult spotted lanternfly has a head and eyes similar to the closely related cicada

Common Name: Spotted Lanternfly, Chinese blistering cicada, Spot clothing wax cicada – The term lanternfly is generally applied to several families of planthopper insects even though there is no known species that emits light. Most planthoppers are small insects that are colored to blend into the backdrop of greens and browns. This species of lanternfly is distinctive in having prominent spots on its folded forewings.

Scientific Name: Lycorma delicatula – Lyco is Latin for wolf and could possibly be in reference to a color or texture of the body or wings. A more plausible etymology is a derivative of lychnus, Latin for lamp. The species name means dainty or nice. So, it could be construed as delicate lamp, consistent with the common name.

Potpourri: The spotted lanternfly is the latest North American invasive insect invader. It has taken its place alongside Japanese beetles, gypsy moths (spongy moths since 2022), and woolly adelgids in the rogue’s gallery of unwelcome invertebrates.  The invasive species epidemic is the unintended yet almost inevitable result of global trade in shipping containers that pass from continent to continent with almost anything inside in numbers that preclude anything close to universal screening. The spotted lanternfly has followed the invasive biological playbook in reproducing geometrically, eating everything in sight, and taking advantage of an environment devoid of any serious predation. It is unique among insect pests in having been preceded by its favorite host plant, Ailanthus altissima or tree of heaven, which was imported from Asia and intentionally planted for its robust tenacity and rapid growth. It was the tree of Betty Smith’s iconic “A Tree Grows in Brooklyn.” It became the tree that grows everywhere in North America as a ready source of food for its Asian lanternfly cohort.

The spotted lanternfly is a planthopper, a group consisting of mostly tropical, inconspicuous insects that are easily confused with treehoppers, leafhoppers, and froghoppers in the “endless forms most beautiful” of the class Insecta. In that they extract the liquid nutrient produced by plants with a hollow beak, literally sap-sucking, they are generally placed in the order Hemiptera. These are the true bugs as opposed to the more common use of the word bug for almost any insect like ladybugs that are beetles. Hemiptera is Latin for half wing, referring to the forewing that is solid at the base and membranous at the tip. Some entomologists separate those bugs with wings that are membranous from base to tip in a separate suborder Homoptera meaning same wing. The homopterans consist of three broad groups: cicadas, aphids, and planthoppers. [1]

As a close cousin of aphids and cicadas, it is easy to understand why there might be a problem with spotted lanternflies. Aphids are perhaps the most economically damaging insect in the global temperate regions that constitute the breadbasket for most of humanity. Cicadas are masters of reproduction, producing millions of offspring in seventeen, thirteen, or single year cycles. The spotted lanternfly reproduces with cicada fecundity and sucks sap with aphid voracity. Having been first introduced into Pennsylvania in 2014, they have spread with Malthusian certainty over the mid-Atlantic states to the extent that there is a hue and cry for some form of countermeasure before epidemic populations ensue. This will be difficult if not impossible since they feed on a wide variety of plants, are not palatable to most insect predators, deposit mounds of excrement called honey dew that attracts other pests and pathogens and pass from the scene only after having mated and laid massive egg deposits that are well protected and hidden by a waxy overcoat. [2]

The bright orange contrasting wing bars may be a aposematic warning of toxicity to birds.

Even though spotted lanternflies prefer the tree of heaven, they are not finicky. They have been found feasting on over 100 different hosts from 33 plant families that include but are not limited to vines, ornamentals, specialty plants and fruit trees. The list of plants narrows considerably as they grow and molt. Like all insects, lanternflies have a life cycle based on metamorphosis. They overwinter as eggs that hatch in spring as nymphs that are black with white spots that must extract plant sap to survive. As they grow over the next several months, they literally get too large for the original carapace and must molt several times to form a new, somewhat larger body called an instar.  The first three instars are similarly diminutive and inconspicuous nymphs that move to ever larger plants to provide the additional amount of nutrients needed for their larger-sized appetites.  The fourth instar marks a radical change in appearance. The adult is metamorphosed by evolution’s magical genetics into a much larger body with moth-like wings that are brightly colored with stark contrast. It is the adult spotted lanternfly that is nemesis of vineyards and orchards. [3]

Brightly colored defenseless animals seem a contradiction. The goal of every living thing is to reproduce to perpetuate the species. Getting eaten before mating and oviposition leads to genetic extinction. Many animals hide from predators by adapting their coatings to match the colors and textures of their environment. This is called crypsis. However, if an animal is poisonous to its predators it is advantageous from the evolutionary perspective to make that clear in advance. It does not help if the poison is only detected after the insect’s body is mangled. Bright coloration to alert predators of potential toxicity is called aposematism. The monarch butterfly, which consumes the poisonous milkweed plant is the classic example. And this, apparently, is where the tree of heaven comes in. A simple field test of this predator alert effect on birds was conducted using two different batches of suet, one made with crushed spotted lanternflies that had eaten Ailanthus altissima and one with spotted lanternflies that had not. Birds preferred the latter, demonstrating that consuming tree of heaven was effective in protecting the spotted lanternfly. [4] That they actually evolved their distinctive bright orange wing bars to indicate toxicity is correlated but not proven. It has been suggested that the closed forewings are cryptic so that the spotted lanternfly can hide on tree trunks but that the aposematic flash of orange occurs when they are under attack by a pecking bird.  

If the spotted lanternfly ate only A. altissima, that would be a good thing. Were it not for its other inimical activities, it could even be considered a biological control against the tree of heaven, which has invasive problems of its own. This is in part because of its chemistry, producing cytotoxic alkaloids that suppress the growth of other plants. One of its chemicals, named ailanthone for the genus, reduces the growth of other plants by 50 percent at a concentration of only 0.7 ppm. [5] It is not known which of the secondary metabolites of the tree are employed by the spotted lanternfly, but there is some serious chemistry going on. The spotted lanternfly has been used in traditional Chinese medicine since the twelfth century to reduce swelling, presumably due to its tree derived toxins.  Spotted lanternflies have become a biological bane due primarily to their second favorite food, the plant sugars fructose and sucrose that are especially concentrated in the genus Vitis, which includes the various grapes of the global wine industry. [6] In North America, there are 40 other known hosts, including black walnut, tulip tree, oriental bittersweet, multiflora rose, and hops, a key beer flavoring ingredient. [7]

Sap sucking insects require the same three basic inputs necessary for all plants, animals, and fungi: carbohydrates for energy, lipids for membranes, and proteins for amino acids. Sap is high in carbohydrates but low in protein. Much more sap must be extracted than is needed for carbohydrate energy to get enough protein for growth. The result of the extra input of sugar is more output as insect excrement or frass. The high sugar frass produced by sap-sucking insects is fittingly called honeydew. Some ant species herd and protect aphids to collect honeydew as food for their larval offspring. The honeydew of spotted lanternflies becomes a social problem due to their numbers and the volume excreted. The sticky goo builds up on whatever is underneath, which may include things like picnic tables and lawn furniture that become stained with mold. Honeydew is also attractive as a food source for stinging insects like yellow jackets that are disruptive to outdoor human activities.  [8]

The ootheca are almost impossible to see in between ridged tree bark

The global spread of spotted lanternflies is mostly due to the coating that they apply to their eggs that both conceals and protects them. Each gravid female lays about 40 eggs and then secretes a brownish, waxy substance to cover them. The end result is an oothecum, a thick-walled egg case similar to that made by cockroaches. While most insects lay eggs on host plants that will serve as the first meal for the emergent larvae or nymphs, spotted lanternflies will use almost any available surface with a preference for the vertical. In most cases, the ootheca are further protected by placement in obscure locations that range from tree bark fissures several meters above the ground to stone monoliths and building walls. Once the process is complete, the ootheca are almost impossible to find absent a detailed inspection which can only be effective if you already have a good idea where to look. As the egg casing ages, it looks more and more like dried mud, making identification even more challenging. It is believed that the first spotted lanternflies arrived in Pennsylvania as an oothecum attached to a shipment of landscaping stones, almost certainly sent in a shipping container from Asia. [9]

Control and containment of the spotted lanternfly is evolving in concert with its radiating spread outward from its point of origin with concomitant economic damage. Estimates at this point are speculative as they are based on extrapolation of local damages in infested areas. Pennsylvania, where the spotted lanternfly first appeared, may see damages of up to $100 million annually due to crop loss. If spotted lanternflies spread to the Pacific Northwest, losses to cherry, wine grape, and hops crops in Washington are estimated at about $4 billion.  Two spotted lanternflies have already been found in Oregon on packing containers and ceramic pots that both came from Pennsylvania. They were dead, but egg cases cannot be too far behind. [10]

The three basic methods to exterminate pest insects are mechanical, chemical, and biological. Mechanical means range from the satisfying but fruitless attempts to find and squash the bugs to affixing host trees with some form of baited trap. In the case of lanternflies, glue coated sheets, some with attractive pheromones, have been tried with limited success but with the caveat that bycatch of birds and butterflies is always a concern. As discussed above, finding and scraping egg masses is not feasible and getting rid of its preferred tree of heaven host that are the dominant tree along many miles of US highways would be nearly impossible.

This leaves chemical and biological as the only two viable means to combat the spotted lanternfly invasion. Pesticides like neonicotinoids (Dinotefuran is prescribed by federal agencies) and organophosphates are effective, but they are general agents that have been implicated in reducing beneficial insect populations like honeybees. The other problem with pesticides is the development of immunity by species through natural selection. There will almost always be individual insects that are resistant to a pesticide due to the randomness of mutation. The resistant mutants survive the poison to propagate their genes, replacing those that were killed by it.  A second issue is the economic cost of using pesticides over large areas, relegating most applications to field size acres instead of the county size square miles that are necessary for extirpation. Vineyards in Korea that were sprayed with pesticide were rapidly repopulated by spotted lanternflies from nearby forested areas. [11]

Biological controls are more promising. A lot of attention has been paid to the role of birds, which are put off by the toxins that spotted lanternflies extract from the tree of heaven.  It was even suggested that if 70 percent of the spotted lanternflies could somehow be kept from their favorite food, then birds would do the rest. This was proffered with the caveat that “we need to do everything we can” even if this cannot. [12] The best place to look for biological controls is in the country of origin, where the local ecosystem keeps the target species in check. One promising possibility is a wasp native to China that parasitizes up to 80 percent of spotted lanternflies. However, introducing an alien predator species is cumbersome due to the need to test both its efficacy on the target species and its possible harmful effects on other species. However, biological control is in all likelihood the only way to prevent the dystopia of spotted lanternfly proliferation over the long term.

References:

1. Marshall, S. Insects, Their Natural History and Diversity, Firefly Books, Buffalo, New York, 2006, pp 91-104.

2. . “Spotted Lanternfly Pest Alert” (PDF). USDA-APHIS. USDA https://www.aphis.usda.gov/sites/default/files/alert-spotted-lanternfly.pdf  

3. Barringer, L. “Lycorma delicatula (spotted lanternfly)”. www.cabi.org. 17 December 2021

4. Kranking, C. “Birds Are One Line of Defense Against Dreaded Spotted Lanternflies” Audubon Magazine, 17 September 2021. https://www.audubon.org/news/birds-are-one-line-defense-against-dreaded-spotted-lanternflies    

5. https://hikersnotebook.blog/flora/deciduous-trees-and-shrubs/ailanthus-tree-of-heaven/

6. Dara, S.; Barringer, L.;  Arthurs, S. (2015). “Lycorma delicatula (Hemiptera: Fulgoridae): A New Invasive Pest in the United States”. Journal of Integrated Pest Management. 20 November 2015 Volume 6 Number 1. pp 1–6. https://academic.oup.com/jipm/article/6/1/20/2936989?login=false

7. Murman, K, et al. “Distribution, Survival, and Development of Spotted Lanternfly on Host Plants Found in North America”. Environmental Entomology. 31 October 2020 Volume 49 Number 6. pp 1270–1281. https://academic.oup.com/ee/article/49/6/1270/5947504?login=false

8. Barringer, op cit.

9. . Urban, J..; Leach, H. “Biology and Management of the Spotted Lanternfly, Lycorma delicatula (Hemiptera: Fulgoridae), in the United States”. Annual Review of Entomology. 23 January 2023. Volume 68 Number 1 pp. 151–167. https://www.annualreviews.org/content/journals/10.1146/annurev-ento-120220-111140    

10. Department of Agriculture. “Pest Alert: Spotted lanternfly Lycorma delicatula”. Oregon Department of Agriculture Fact Sheets and Pest Alerts    https://www.oregon.gov/oda/shared/Documents/Publications/IPPM/SpottedLanternflyPestAlert.pdf              

11. Dara. S. et al op cit.

12. Grandoni, D. “Squashing lantern flies (sic) isn’t enough; it might be time to send in the birds” Washington Post 7 March 2024.