In Praise of Poison Ivy

This is a guest post by Margaret Gargiullo. Visit her website, Plants of Suburbia, and check out her books for sale on Amazon.

———————

No one seems to like Toxicodendron radicans, but poison ivy is an important plant in our urban and suburban natural areas. Poison ivy (Anacardiaceae, the cashew family) is a common woody vine, native to the United States and Canada from Nova Scotia to Florida, west to Michigan and Texas. It is also found in Central America as far south as Guatemala. It is all but ubiquitous in natural areas in the Mid-Atlantic United States. It has been recorded in over 70 wooded parks and other natural areas in New York City.

Leaflets of three? Let if be. Poison ivy (Toxicodendron radicans). photo credit: wikimedia commons

Leaflets of three? Let if be. Poison ivy (Toxicodendron radicans) – photo credit: wikimedia commons

Poison ivy does have certain drawbacks for many people who are allergic to its oily sap. The toxins in poison ivy sap are called urushiols, chemicals containing a benzene ring with two hydroxyl groups (catechol) and an alkyl group of various sorts (CnHn+1).

These chemicals can cause itching and blistering of skin but they are made by the plant to protect it from being eaten by insects and vertebrate herbivores such as rabbits and deer.

Poison ivy is recognized in summer by its alternate leaves with three, shiny leaflets and by the hairy-looking aerial roots growing along its stems. In autumn the leaves rival those of sugar maple for red and orange colors. Winter leaf buds are narrow and pointed, without scales (naked). It forms extensive colonies from underground stems and can cover large areas of the forest floor with an understory of vertical stems, especially in disturbed woodlands and edges. However, It generally only blooms and sets fruit when it finds a tree to climb. When a poison ivy stem encounters a tree trunk, or other vertical surface, it clings tightly with its aerial roots and climbs upward, reaching for the light (unlike several notorious exotic vines, it does not twine around or strangle trees). Once it has found enough light, it sends out long, horizontal branches that produce flowers and fruit.

Flowers of poison ivy are small and greenish-white, not often noticed, except by the honeybees and native bees which visit them for nectar and exchange pollen among the flowers. Honey made from poison ivy nectar is not toxic. Fruits of poison ivy are small, gray-white, waxy-coated berries that can remain on the vine well into winter. They are eaten by woodpeckers, yellow-rumped warblers, and other birds. Crows use poison ivy berries as crop grist (instead of, or along with, small stones) and are major dispersers of the seeds.

The fruits of poison ivy (Toxicodendron radicans) - photo credit: Daniel Murphy

The fruits of poison ivy (Toxicodendron radicans) – photo credit: Daniel Murphy

It is as a ground cover that poison ivy performs its most vital functions in urban and suburban woodlands. It can grow in almost any soil from dry, sterile, black dune sand, to swamp forest edges, to concrete rubble in fill soils, and along highways. It enjoys full sun but can grow just fine in closed canopy woodlands. It is an ideal ground cover, holding soil in place on the steepest slopes, while collecting and holding leaf litter and sticks that decay to form rich humus. It captures rain, causing the water to sink into the ground, slowing runoff, renewing groundwater, filtering out pollutants, and helping to prevent flooding.

Poison ivy is usually found with many other plants growing up through it – larger herbs, shrubs, and tree seedlings that also live in the forest understory. It seems to “get along” with other plants, unlike Japanese honeysuckle or Asian bittersweet, which crowd out or smother other plants. Poison ivy is also important as shelter for birds and many invertebrates.

While those who are severely allergic to poison ivy have reason to dislike and avoid it, Toxicodendron radicans has an important place in our natural areas. No one would advocate letting it grow in playgrounds, picnic areas, or along heavily used trail margins, but it belongs in our woods and fields and should be treated with respect, not hatred. Recognize it but don’t root it out.

———————

Further Reading: Uva, R. H., J.C. Neal and J. M. DiTomaso. 1997. Weeds of the Northeast. Comstock Publishing. Ithaca, NY.

This piece was originally published in the New York City Dept. of Parks & Recreation, Daily Plant.

Botany in Popular Culture: Black Orchid

Black Orchid coverBlack Orchid is a minor character in the DC Comics universe. She is a superhero with a troubled past, and although she first began appearing in comic books in 1973, her origin was a mystery until 1988 when Neil Gaiman wrote his 3 part mini-series entitled, Black Orchid, revealing that she was a plant-human hybrid created by Dr. Philip Sylvain after combining the DNA of Susan Linden-Thorne with the DNA of an epiphytic orchid.

Curiously, in order to reveal Black Orchid’s origins, Gaiman has the namesake of his series killed off within the first few pages. A master of disguise, Black Orchid is following her standard modus operandi of impersonating someone in order to infiltrate enemy headquarters. In this case she is pretending to be a secretary in Lex Luthor’s employ. While sitting in on a board meeting in which the activities of Luthor’s crime ring are being discussed, her secret identity is revealed, which leads to her being tied to a chair and shot through the head. The bullet doesn’t kill her though since invulnerability to bullets is one of her superpowers (along with flight, super strength, shape shifting, and others). However, the building is also set on fire, and ultimately all that is left of Black Orchid at the end of the night are some charred plant remains.

The story can’t end there though, so as Black Orchid goes up in flames, two of her clones emerge from flower buds in Dr. Sylvain’s greenhouse. They aren’t sure what they are at first. They have some of Susan’s memories but don’t know what to make of them. One of them is a child called Suzy, and the other is an adult who eventually gets the name Flora Black. They find their way to Dr. Sylvain who tells them the story of how they and the original Black Orchid came to be.

Dr. Philip Sylvain tells the Black Orchid clones about how he

Dr. Philip Sylvain tells the Black Orchid clones about his childhood with Susan Linden.

Susan was Dr. Sylvain’s childhood friend. They spent lots of time in the garden together learning about plants and growing things. But Susan was abused regularly by her father and eventually ran away as a teenager. Dr. Sylvain didn’t see her for many years, and in the meantime grew up and became a botanist. At university, Dr. Sylvain studied with Jason Woodrue, Pamela Isley, and Alex Holland, each of whom went on to become plant-human hybrids of some sort (Floronic Man, Poison Ivy, and Swamp Thing respectively). Dr. Sylvain had ambitions of making “people of plants” as part of a plan to save a dying earth. His ambitions remained a dream until Susan returned.

Dr. Sylvain's friends from university who later became plant-hybrid heroes and villians.

Dr. Sylvain’s friends from university who later became notorious plant-human hybrids.

Susan was running away again – this time from her abusive husband, Carl Thorne, who worked for Lex Luthor as an arms dealer. Thorne was in trouble with the law and was ultimately put on trial for his crimes. Susan came to Dr. Sylvain seeking refuge. She was set to testify against her husband, but before she could do that, Thorne killed her. Dr. Sylvain then used Susan’s DNA to create the crime fighting, superhero, Black Orchid.

Coincidentally, as the original Black Orchid is being killed and the two new Black Orchids are emerging, Thorne is finishing his prison sentence and being released. He first goes to Luthor to try and get his job back, but is turned away. Next he goes to Dr. Sylvain’s house where he discovers the newly emerged Black Orchids. He alerts Luthor, who sends a team to hunt down the “super-purple-flower women” and bring them back to the lab for “examination and dissection.” The rest of the series details the Black Orchids’ mission to make sense of who they are and what their purpose in life is while simultaneously contending with Luthor’s men (and Thorne) who are out to get them. Flora Black meets with Batman, Poison Ivy, and Swamp Thing along the way, filling in her origin story and gaining instruction and insight about her future as a superhero.

Gaiman is a popular, prolific, and well-respected author; however, this is the first of his books that I have read. I was impressed by his storytelling and appreciated the departure from the typical superhero vs. villain narrative. Dave McKean did the artwork for this series, which was an excellent decision as his work is also quite atypical for the genre. His illustrations gave the book a mystical feel as the panels altered from standard storytelling sequences to abstract, fantasy pieces.

This Black Orchid storyline continued for several issues after Gaiman’s three part mini-series without Gaiman as the author. Flora Black was eventually killed off. A new version of the Black Orchid character currently appears in the ongoing Justice League Dark series.

Alba Garcia (aka Black Orchid), a member of Justice League Dark

Alba Garcia (aka Black Orchid), a member of Justice League Dark

You can read more about Black Orchid on her Wikipedia and Comic Vine pages.