Mayapple

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Common Name: Mayapple, American mandrake, Indian apple, Ground lemon, Umbrella plant, Duck’s foot, Vegetable calomel – The plant produces a singular white flower in May that results in a fruit in June or July that initially resembles a small green apple until it turns yellow with age. It is incongruously named Mayapple in combining the May flower with the June fruit.

Scientific Name: Podophyllum peltatum – The genus is a combination of the Greek words pod meaning ‘foot’ and phyllum meaning ‘leaf’ to describe the elongated foot-like structure of each palmate leaflet lobe. The species name is from pelte, a small Greek shield, the intent is to characterize the umbellate arrangement of the leaves centered over a singular petiole.

 

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Mayapple emerging in spring

Potpourri:  The Mayapple is one of the first plants to emerge in the spring to take advantage of the relatively short window of sunlight energy availability on the forest floor that precedes the emergence of the shading arboreal leaf canopy; they senesce in early summer. It may be described as a rhizomatous perennial that grows in clonal patches, meaning that it extends horizontally by epigeal roots (rhizomes) that advance every year until the single initial plant has spread to blanket the habitat, typically a boggy area in dense woods. The rhizome radiates from the initial seedling in all directions, forming nodes from which the individual plant structures arise. In the spring, a plant emerges from each node in one of two forms: A single petiole, single-leaf physiology which is an asexual clone and therefore has no flower; or a forked petiole, double-leaf physiology which is a sexual clone that produces a flower that blooms in May at the juncture of the two petioles. The Mayapple is therefore actually a May flower not to be confused with the Canada Mayflower or the Trailing Arbutus, also called Mayflower.

 

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The flower that blooms in May grows only at the juncture of the two petioles

The reproductive strategy of the Mayapple is subject to considerable scientific interest on account of its perplexing contradictions; it is oblivious to the norm of plant evolution that encourages sexual profligacy. The combination of asexual and sexual plants growing along the same cloned rhizome is not a very efficient seed-producing arrangement, the number of flowers being reduced accordingly; this is compounded by the observation that sterile single-stalk growth generally exceeds the potentially fertile double-stalk growth. The flowers that do emerge on the forked variety have no nectar and no scent, lacking both of the two primary methods that plants use to attract pollinators. According to a 2008 article by J. Crants entitled Pollination and Pollen Limitation in Mayapple “Its fecundity is pollen-limited because its flowers are nectarless (sic), and native pollinators do not collect its pollen.” The author reports in confirmation that he had observed Mayapple flowers over time for pollination activity and measured a rate of .03 to .06 visits per flower per hour; for the sake of practicality, this would equate to one visit about every 15 hours, very rarely indeed. There is one other strategy that has evolved to deal with poor pollen transfer conditions – the perfect flower, also known as self-compatibility. This refers to the ability of a flower to pollinate itself, i.e. for the pollen from its anthers to fertilize the ovules in its own pistil. However, Mayapple blossoms are for the most part self-incompatible, this having been demonstrated by experiment – no seeds are produced when a Mayapple flower is manually self- pollinated by human intervention. The combination of a paucity of self-incompatible flowers with a lack of any means of pollinator attraction would seem to doom the Mayapple to eventual extinction, but it thrives nonetheless. How can this be?

 

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Orange Mayapple Rust (Puccinia podophylli)

The answer lies beneath the soil, where the spreading rhizome of the Mayapple is provided with water and minerals by fungi called vesicular arbuscular mycorrhiza (VAM) that penetrate its individual root cells. Mayapples are obligate to their fungal partners, as they cannot function without them. The root-like structures of the fungus called hyphae extend up to about 8 inches from the plant rhizome, thereby extending the volume of soil available substantially. In return, the fungi receive nutrients in the form of the photosynthetic products of the plant. The transfer occurs inside the plant cells, where the fungi hyphae penetrate and expand into branched structures called arbuscules (the A in VAM). While the Mayapple plant benefits in having a source of key nutrients, notably phosphorus and water so that it can extend its growth to form the vast clonal patches in choice habitats, the fungus benefits in its own progression. Large aggregations of spores, the reproductive bodies of fungi, are formed in nodule-like vesicles (the V in VAM) on the roots of the Mayapple plant. These can be as large as an inch in diameter and are filled with lipids that provide for the long term survival of the fungus should the host plant cease to be viable; the spores eventually germinate to extend new hyphae to find new mycorrhizal partners. The importance of fungi in the growth of plants cannot be overstated, fully 90 per cent all plants benefit from mycorrhizal associations. It is also important to note that VAM fungi are not host specific. According to Bryce Kendrick in The Fifth Kingdom, “VAM fungi can usually relate successfully to a very large number of host species (130 fungal taxa with 300,000 plant taxa).” Fungi can also be parasites, and the May apple, as a result of its own reproductive success, is the host to an obligate parasite appropriately named Mayapple Rust (Puccinia podophylli); the species name is an indication of its association to the genus Podophyllum. The generic name rust derives from the characteristic reddish-brown hues of this group of fungi; in the case of Mayapple rust, its bright orange contrast to the verdant green leaf can be readily distinguished in late spring to early summer.

 

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The fruit of the Mayapple turns yellow when ripe

Every part of the Mayapple is poisonous except the fruit, which is edible; the only concession made by the plant to the propagation of the species. As the fertilized ovule of the flower’s pistil, fruiting requires that the flower (that has no nectar or scent) attracts a pollinator to the concealment on the underside of the umbrella-like leaves. It has been experimentally demonstrated that flower fertilization is enhanced where the Mayapple grows in proximity to flowers that have a great deal of nectar like the wood betony (Pedicularis canadensis); the hypothesis is that clumsy pollinators like moths and bumblebees, blunder into mayapple flowers while feeding on other flowers in the vicinity. The Mayapple fruit, which is normally yellow (May lemon has been suggested as a better name), is eaten by box turtles, birds, and mammals including humans for successful seed dispersal. The taste evokes different sensations that vary from one person to the next. Captain John Smith of Jamestown wrote in 1612 that “a fruit the inhabitants call maracocks a pleasant wholesome fruit much like a lemond,” whereas Samuel Champlain, the French explorer, wrote in 1619 that “one of their berries is new to us. It looked rather like a small lemon but tasted more like a fig.” It has been made into jams, jellies and pie filling and is a notable staple of the cuisine of the Appalachian mountain people. The “Hoosier Poet” James Whitcomb Riley imbued the mayapple with ineffable delectation in the classic 1890 Rhymes of Childhood

And will any poet sing
Of a lusher, richer thing
Then a ripe May-apple, rolled
Like a pulpy, lump of gold
Under thumb and finger tips,
And poured molten through the lips.

I am not sure I would go quite that far; some people find it nauseous and there are many cautions against eating the seeds. It is well to note that Mayapple has a long history as a medicine, an insecticide, and even worse; it is a potent poison.

The virulent toxicity of the Mayapple was well known to Native Americans, so much so that they used it for suicidal purposes, a fact that is well documented, if contrary to the general notion of the animist coexistence with nature with which they are traditionally associated. The Moravian missionary David Zeisberger wrote in 1779 that “In the use of poisonous roots, the Indians are well versed, and there are many melancholy examples where they have, by their use, destroyed themselves and others.” The French naturalist Michel Sarrazin was a little more descriptive about his experiences with the Indians of New France: “The root (of the Mayapple) is a very effective poison which the savages use when they cannot bear their troubles.” It is likely that the underreporting of suicide in the historical record written largely according to religious precepts masks its centrality to the human condition, and that the rise in suicide in the last half century is a matter of better reporting and not a matter of the increased stress due to the frenetic pace of modern life. It is important to note that the death inducing use of Mayapple was the extreme and not the norm for its use by Indians. A diluted decoction of roots and leaves was used widely as a vermifuge to treat intestinal worms and as a laxative ptisan. It was even used as an insecticide by many eastern tribes to protect their crops; the Cherokee soaked corn seeds in it before planting and the Menominee sprinkled it on potato plants, among many others. The use by the Native Americans was passed on to the colonial Americans to the extent that the noted autodidact naturalist Constantine Rafinesque wrote that Mayapple was “one of the best native cathartics … the medical properties have been well ascertained, and are admitted by all physicians; many use it frequently in the country… ten grains of the powder alone, taken at night, purges next morning.” The expressed universal use of Mayapple as a pharmaceutical is most attributable to William Bartram, the son of the well-known naturalist John Bartram, considered by Carolinus Linnaeus to be the world’s greatest botanist. He applied his Quaker universalism to his travels in the Indian back country of the South in the late 18th Century and learned of their mastery of herbal medicine. Of the Mayapple he wrote: “the root is the most effectual and safe emetic and efficacious in expelling worms from the stomach – the lives of many thousands of the people of the southern States are preserved, both children and adults.” His work led to the development of the first United States Pharmacopoeia in 1820 which included 296 substances of which 130, including Mayapple, were of Native American provenance.

There is a very good reason why Mayapple was widely used – because it was – and is – good medicine; the name American mandrake reflects is similarity to the European mandrake (Mandragora officinarum) also known for the magical powers of its roots. It was first investigated at the start of the “Pharmaceutical Revolution” of the 20th Century based on its historical use in both North America and Asia. In 1947, J. Hartwell and M. Shear published “Chemotherapy and Cancer: Classes of Compounds under Investigation and Active Compounds of Podophyllum” in Cancer Research to report on the demonstration of the effectiveness of Mayapple in tumor reduction. Subsequent research on lignin glycosides derived from Podophyllum isolated the compound podophyllotoxin and ultimately to two of the primary drugs used in cancer treatment: etoposide and teniposide. The Mayapple-derived drugs work by blocking mitosis (cell division) and are currently used in the treatment of a many cancers including leukemia, pancreatic, testicular and lung. Research is continuing on the potentialities of Mayapple compounds in the treatment of rheumatoid arthritis and psoriasis. Podophyllotoxin has been traditionally extracted from a cousin of the North American Mayapple that grows in the Himalayas (Podophyllum emodi). The similarity of species on opposite sides of the Pacific Ocean is not at all unusual (the tulip poplar tree is also an Asiatic offshoot); it results from common origins and the physical separation for the continents from Pangaea. The increasing demand for Podophyllotoxin (130 tons in 1970) has led to a rapid depletion of the Asian variant to the extent that it is now endangered. The North American Mayapple, while less potent than its Himalayan cousin, is being examined as a replacement. The new ginseng perhaps.