ommon Name: White Mulberry, Black-fruited mulberry, Mulberry bush, Silkworm mulberry, Chinese white mulberry, Russian mulberry, Chi sang, Moral blanco – The name mulberry is from a combination of the Old French moure (see Morus below) anglicized to mul and the Old English berie.
Scientific Name: Morus alba – The generic name comes directly from morus, the Latin name for the mulberry tree; the species name is Latin for white.
Potpourri: There is a great deal of diversity in the taxonomy of the Morus genus, likely a result of the wide geographic distribution of the tree and the degree to which it has been hybridized. There are about 15 recognized species world wide and over ten times that many cultivars, mostly in Asia, that are considered separate species by some. The USDA recognizes four species: white, red (M. rubra), black (M. nigra), and Texas (M. microphylla). The different species share a generic similarity in the general appearance of their fruits, which consist of an aggregation of berries in a cluster that ranges in color from white to deep purple.
Though the red mulberry is native to North America, the white mulberry of East Asia is widely naturalized after having been intentionally imported to support sericulture, the manufacture of silk. It is considered an invasive weed according to some references. The white mulberry is the predominant food of the silkworm, Bombyx mori, the species name attests to its preference for the Morus genus. The use of silkworms to produce silk fabric is attributed to the Chinese empress His-ling Shih, who allegedly discovered the method in 2640 BCE. The silk industry was surreptitiously extended to Byzantium during the reign of Emperor Justinian (527-565 CE). According to the prevailing legend, two Persian monks managed to smuggle silkworm eggs and mulberry seeds out of China in hollow staves. Sericulture subsequently spread to the Arab states in the 8th Century and to Italy, Spain and France in the 12th Century. The silk industry literally emigrated to England when the French King Louis XIV, who had apotheosized himself as the “Sun King,” repealed the Edict of Nantes in 1685 (The Edict was issued by King Henri IV in 1598 to end the persecution of the French Calvinist Protestants known as the Huguenots; its revocation made Protestantism illegal). Consequently, most of the Huguenots left France for other countries; a group from Lyon, skilled in sericulture, settled near London.
Though the silk industry in England initially prospered, it gradually though irrevocably succumbed to the better quality and cheaper prices of foreign silk; it is ironic given the origin of the silk industry that France was England’s major competitor. One of the key productivity problems was the importation of raw silk for the looms. Attempts to establish a viable mulberry-silkworm biocenosis in England failed due to the notoriously cool and moist climate of the British Isles, silkworms flourish only within a relatively narrow temperature range. An obvious if faulty hypothesis was that the warmer and more humid American Colonies would provide the necessary environmental factors for silk production. The spread of the white mulberry tree to North America was thus a part of an intent to establish a viable commercial enterprise in the colonies; King James I sent silkworm eggs and mulberry seeds to his namesake colony in the early 17th Century and directed that the colonial government plant mulberry trees for the silkworm. This original attempt quickly failed, but the white mulberry tree became established.
This was not, however, the end of the silk industry in America. Sericulture was thought to be so clearly achievable in the United States that it was for many years considered an advisable business investment. This sentiment was manifest by the passage of a resolution in the U. S. House of Representatives on 11 May 1826 to issue a manual on the economic opportunities of silkworms and mulberry trees. The Secretary of the Treasury responded with a 220 page manual entitled “Growth and Manufacture of Silk” in February of 1828 that extolled the lucrative potential of the enterprise; over six thousand copies of the manual were sold to aspiring sericulturists. The promise of a quick fortune in the silk trade fueled a decade-long speculative bubble. The early 19th Century was fraught with various agricultural crazes that were driven by the economic realities of the times. Agricultural production was moving west to the rich Ohio River Valley; those left in the east sought viable alternatives.
The mulberry craze started with the planting of tracts of mulberry trees by well-intentioned entrepreneurs seeking to fulfill the desire of the government to establish an American silk industry. The spirit of Yankee ingenuity extended to the choice of tree; a cultivar of the white mulberry called the many-stalked mulberry (M. multicaulis) was preferred for its larger leaves which would provide more food for the voracious larvae. By about 1834, the difficulties associated with silkworm production in the relatively cold climate of New England became manifest to the early adopters, who were now stuck with plantations of mulberry trees. Among this group, ever-enterprising individuals with questionable moral scruples promoted the sale of mulberry trees for silk production. A four-page pamphlet published in 1834 by William Kendrick, the owner of a nursery near Boston extols M. multicaulis as “decidedly superior over all others” that “braves the most rigorous winters of France” that was so profligate that “two crops of silk may be produced in a single season.” With shameless hucksterism, he continues with an appeal to the patriotism of the hapless reader to help staunch the flow of capital for imported silk through “unceasing toils, and mighty efforts, and matchless labors” to make silk that will “add to the substantial wealth of the nation and to the glory of the whole republic.” Because of Panglossian treatises such as this, the price of mulberry saplings went from $4 per 100 saplings in 1834 to $30 per hundred in 1836, encouraging more people to plant mulberry trees. By 1839, the bubble was at its peak when prices soared to $500 per hundred trees, the trees becoming at this point too valuable to feed to silkworm larvae. The cold winter of 1839-1840 combined with an inevitable economic downturn burst the bubble, leaving many speculators bankrupt. A fungal blight killed off most of the multi-branched mulberry trees in 1844; the white and red mulberry trees survived.
The white mulberry figures prominently in cultural references that extend from ancient Rome to English nursery rhymes. As written in Ovid’s “Metamorphoses,” Pyramus was the most handsome of eligible men and Thisbe the most beautiful of all maidens in Babylon. They were forbidden to associate by their families so they expressed their mutual love through a chink in the garden wall that extended between their neighboring houses. Mounting frustration resolved them to meet at night under a white mulberry tree next to a spring at the nearby tomb of Ninus. Thisbe, veiled against the night, arrived first and sat under the mulberry tree there to espy a lioness who had stopped to drink at the spring, its jaws covered with the blood of its most recent prey. Frightened, Thisbe ran, inadvertently dropping her veil which the lioness found and shook, marking it with the bloody gore of carnage. Pyramus arrived to find the veil, concluded that Thisbe had been eaten by a lion and, in anguish, promptly drew his dagger and plunged it into his heart. His blood immediately stained the white mulberries red and soaked the ground that bore the roots of the tree, thus tainting the tree and all of its fruits. Thisbe returned with trepidation to find Pyramus dead of his own hand with her bloody veil clutched to his chest. With the bathos of romantic tragedy, she took his dagger and plunged it into her own breast, succumbing with an imprecation to the mulberry tree to “retain the marks of slaughter. Let thy berries still serve for memorials of our blood.” And the white mulberry tree accordingly has purple berries to this day.
“Here we go round the mulberry bush” resonates with many adults imprinted as children with the familiar nursery rhyme with the “jack-in-the box” tune. In one of the more common American versions, it goes: “All around the mulberry bush, the monkey chased the weasel, the monkey stopped to pull up his sock, Pop! goes the weasel.” Though speculative, it is credible that the words refer to the English textile industry, where children (monkeys) were employed to restore the loom shuttle (weasel) to its proper place on the loom. The pop referring to the noise made by the weaver in knocking the shuttle back and forth on the resumption of loom operation.