The Amazing Mayapple

mayapple leaves carpeting ground by Martin LaBa

mayapple leaves carpeting ground by Martin LaBar (Creative Commons BY-NC)

After twelve years, the first mayapples bloomed inside our three-acre deer exclosure. Almost as soon as we put the fence up in March 2001, mayapple leaves popped up in the lower, wet, wooded section of the exclosure. But they were single leaves, not the double leaves with a notch in the middle from which a single, six-petaled, waxy, white flower would emerge.

Last spring on our mountain the first umbrella-shaped mayapple leaves unfurled on March 30, by far the earliest date ever for this wildflower that often doesn’t flower until the second week in May. The frosts of April didn’t wilt the leaves, and on the 18th of April, I found three double-leaved mayapples in the exclosure, each bearing a large flower bud.

The exclosure isn’t the only place mayapples bloom. These clonal plants have formed large colonies beside our road, along Sapsucker Ridge Trail, and beside the Far Field Road. But the largest colony of all covers more than an acre at the Far Field thicket. One leaf even appeared in the middle of the Far Field last spring, but I doubt it will make much headway against the goldenrod and asters.

As usual the first mayapples bloomed along the Far Field Road on April 27, the earliest blooming date ever during our 40 years here, but those mayapples beside our access road didn’t flower until May 1, right in time for May Day.

While the first part of its common name refers to the month it usually flowers in, the “apple” refers to the yellow-green, egg-shaped fruit that is purported to appear in August or September after the plant has fallen down. I say purported because I’ve never actually found a fruit on any of our mayapples. Although the deer allow our mayapples to leaf and flower, they never allow them to fruit. Or maybe the culprit is the occasional eastern box turtle that finds and devours the odd fruit. Apparently, the seeds inside the fruit must go through the gut of a box turtle in order to germinate.

I had always hoped to find enough mayapples to make Euell Gibbons’s mayapple marmalade, which he describes as “ambrosia” in his delightful book on wild foods Stalking the Wild Asparagus. (He also says that “the woods are full of ripe Mayapples.”) Despite having a laxative effect on some people, many have found the taste of mayapple fruit worth the risk. Back in 1612 Captain John Smith described it as “a fruit that the Inhabitants call Maracocks, which is a pleasant wholesome fruit much like a lemond (sic).” The Huron Indians gave it to the French explorer Samuel Champlain in 1619, and he thought it tasted like a fig. Early Rhode Island settlers called it “a pleasant fruite (sic).” Gibbons claims that the flavor “is not easily described…When I eat a thoroughly ripe May apple, I am reminded of several tropical fruits, the guava, the passion fruit and the soursop, but I can’t honestly say that it tastes like any of them.”

Girl balancing mayapple blossom on her nose

Girl balancing mayapple blossom on her nose, by talkingplant (Creative Commons BY-NC-ND)

Even its odor was debated, and Charles F. Saunders, in his book Edible and Useful Wild Plants of the United States and Canada, describes the strong scent of the ripe fruit as a composite of cantaloupe, summer apples, and fox grapes. Gibbons writes that “I love the sweet scent of the ripe fruit with its hint of mysterious muskiness.” But all of this is hearsay as far as I’m concerned.

Despite the appeal of its ripe fruit, its raw leaves and roots are poisonous. Native Americans used the plant to commit suicide and made an insecticide from it to kill corn worms. Today it is an ingredient in laxatives and is useful for the treatment of intestinal worms.

But its most important use derives from its ability to produce podophyllotoxin, which is “the starting material for the semi-synthesis of the anti-cancer drugs etoposide, teniposide and etopophus,” according to Rita M. Moraes, Hemant Lata, Ebru Bedir, Muhammad Maqbool, and Kent Cushman in their paper “The American Mayapple and its Potential for Podophyllotoxin Production.” These compounds have been used to treat lung, testicular, stomach and pancreatic cancers, and some leukemias. It’s also a precursor to a new derivative called CPH 82, which may be useful for treating rheumatoid arthritis, psoriasis, and even malaria.

It’s expensive for pharmaceutical companies to synthesize podophyllotoxin and originally, back in the 1970s, when its anti-cancer properties were discovered, the pharmaceutical companies used the rhizomes of our mayapple—Podophyllum peltatum—to produce podophyllotoxin. In one year they harvested more than 130 tons of American mayapple rhizomes.

Then the scientists found that P. emodi, a perennial rhizomatous herb growing in the understory of Himalayan subalpine forests, contained more podophyllotoxin than P. peltatum, so during the next three decades, they switched to the roots and rhizomes of the Himalayan species. The demand by the international market for this plant quickly turned it into an endangered species.

Mayapple with fruit and leaves spotted with rust

Mayapple with fruit and leaves spotted with rust by OakleyOriginals (Creative Commons BY)

For this reason Moraes, Lata, Bedir, Maqbool, and Cushman used a different extractive method on the leaf blades of our mayapple to produce podophyllotoxin. Unlike ripping up the roots and rhizomes, which destroys the plants, leaf blades are a continually renewable resource. Then, too, our mayapple is common and grows in large colonies from northern Quebec and Minnesota to Florida and Texas and west to Nebraska. It also thrives under wide-ranging growing conditions from the low winter temperatures of the north to the high summer temperatures of the south.

Like many spring wildflowers, mayapples reproduce both sexually and asexually. Sexually, bumblebees and other long-tongued bees cross-pollinate the flowers from one clonal colony to another, while asexually the rhizomes continually expand in dense circular clones, usually crowding out any competing vegetation. The plants are one to one and a half feet tall and consist of sterile, immature, palmate-shaped, single leaves or two to three, palmately-lobed, reproductive leaves.

Both its genus name—Podophyllum—which means “foot leaf,” and its species name peltatum meaning “shield-shaped” refers to its leaves. So too do three of its common names—”umbrella leaf,” “duck’s foot,” and “Puck’s foot” (the forest fairy in A Midsummer Night’s Dream).

Its fruit has also inspired several alternative names—”Indian apple,” “hog apple,” (wild pigs love it), “wild lemon,” “ground lemon,” and “raccoon berry.”

Its medicinal uses have given it still more nicknames that need more explanation for modern readers. “American mandrake,” the most popular alternative name for mayapple, referred to one of the most powerful of Old World medicinal herbs, mandrake—Mandragora officinarum—that grows in the Mediterranean countries. Its brown root, which penetrates deep into the ground, often branches and resembles a human figure. While neither the plant nor its flower looks like our mayapple, its fruit is a large, fleshy, yellow to orange-colored berry. It was used as a sleeping pill when the sufferer was in pain or being operated on, as a remedy for depression, and as a purgative. Like mayapple, the plant is poisonous.

Mayapple flower

Mayapple flower by M.W. Fisher Jr. (Creative Commons BY-NC-ND)

“Devil’s apple” may refer to its fruit or, more likely, to its medicinal use, because mandrake is also known as “Satan’s apple.” “Vegetable mercury” probably refers to its similar uses to dog’s mercury (Mercurialis perennis) a poisonous plant that is taken as a purgative or laxative. “Vegetable calomel,” comes from the fact that calomel was used as a purgative and as a fungicide and is also called mercurous chloride, which brings me back to the “vegetable mercury” nickname. “Wild jalop” is similarly confusing. Jalop is a Mexican morning glory used as a purgative, but wild jalop (Ipomoea pandurata), the hated bindweed, is used to treat skin diseases and as a laxative by some herbalists although again it is dangerous to overdose on.

A member of the Barberry family, the mayapple genus has only four species worldwide, our own mayapple and three Asian species. It also has its own fungus—Podophyllum podophylli or the mayapple rust, which only lives and reproduces on mayapple leaves. I find some of the angular, yellow spots on some mayapple leaves every spring.

According to Joan Maloof in her book Among the Ancients: Adventures in the Eastern Old-Growth Forests, the life cycle of the mayapple rust is more complex than that of the mayapple itself. When the mayapple germinates, she writes, a “dark, spiky, club-shaped thing smaller than a grain of sand” also germinates in the forest soil and produces tiny spores. All are in search of mayapple shoots.

When one spore finds a mayapple, it produces a “microscopic, threadlike filament” called a hypha, which is in search of another hypha thread made by a second hypha spore. If they find and merge successfully, they create a hypha with two nuclei in every cell instead of one. They then produce more dark, club-shaped spores which germinate and create a second generation of spores just as the mayapple leaves unfurl. Using wind and/or water, those spores are carried on to the stems and leaves of mayapples. Again the spores germinate and their hyphae look for nutrition and each other.

Under the mayapple parasols by Dave Bonta

Under the mayapple parasols by Dave Bonta

If the spores land on a mayapple stem or vein with sufficient nutrition, they will create more dark, club-shaped structures that will overwinter on dead leaves on the forest floor, but if they “fuse on leaf blades, they will form pockets filled with rust-colored spores,” Maloof writes, that cannot live through the winter. However, she adds that they “can reinfect the plant, germinate, and eventually form the dark overwintering clubs.” The yellow spots on the leaves are a signal that the fungus has used up the food in the leaf cells and infected the leaves. But Maloof calls this “Mother Nature’s yellow and green abstract art work,” rejecting the negative connotation of the word “infect.”

Maloof reminds us, after her discussion of mayapple rust, that a forest is more than its trees. “And in ways we do not yet fully understand, these small things may determine the lives and deaths of trees.” And not only those of trees, but of humans too, in the case of our amazing medicinal American mayapple.