Two Great Locations, One Organization
By Joseph Mooney
Poison ivy leaves-two colors-Annie Roonie

Poison ivy leaves showing two different colors on the same plant. Photo by Annie Roonie.

Poison iovy fall leaves-Alan Schmierer

Poison ivy’s fall leaves are brilliant orange-red and really stand out in the landscape. Photo by Alan Schmierer.

Poison vy flowes-Bob Peterson

Poison ivy flowers are small but quite beautiful. Photo by Bob Peterson.

You read that right: poison ivy (Toxicodendron radicans) is our featured native plant this week.
Not that we recommend seeking out or handling this widespread native plant. In fact, we strongly urge you not to handle poison ivy unless you plan to remove it from your property. Even then you’ll need to take extra care to avoid contact with all parts of the plant. (Also, just saying, this is not a plant to put in your garden.)
Mainly we’re featuring poison ivy this week because it’s 1) native and 2) starting to appear in many local parks and gardens. You can certainly find it in the Arb and at Matthaei. So you’ll want to be able to identify it. But its shape-shifting ways, especially in the leaves, can sometimes make ID difficult even for seasoned spotters.
It can be a vine, growing up a tree and attaching itself with a dense network of hair-like aerial roots. It can be a kind of groundcover, sprawling over the forest floor or a clearing. It can even take the shape of a small upright shrub. How does it pop up in your well-tended garden? Birds and mammals eat poison ivy seeds, and then….
Poison ivy roots-Jay Cross

Poison ivy roots climbing a tree are often covered with a hair-like aerial roots. Photo by Jay Cross.

Black raspberry-leaves-B Walters

Sometimes black raspberry leaves are mistaken for poison ivy. Photo by B. Walters.

Virginia creeper

People often mistake the leaves of Virginia creeper for poison ivy.

Poison ivy berries-Sam Fraser-Smith

Pearl-shaped poison ivy berries are beautiful but contain the skin irritant urushiol found in all parts of the plant. Photo by Sam Fraser-Smith.

The “leaves of three” look different from plant to plant and even on the same plant. They may be dark or light green, shiny or matte, or reddish when first emerging. And T. radicans is often confused with Virginia creeper (Parthenocissus quinquefolia) or plants in the raspberry family.
All parts of poison ivy contain urushiol, an oily compound that causes a rash in almost everyone whose exposed skin comes in contact with it. If you get urushiol on your skin, wash the affected area as soon as possible with cool water and a dishwashing soap or rubbing alcohol. You can also use a specialty product made specifically for contact with poisonous plants such as Tecnu. If removing poison ivy from a garden or landscape, use vinyl gloves and loppers to cut branches (no chain saws!). Bag and dispose of plant material in the trash. And never burn poison ivy. The aerosolized urushiol can be accidentally breathed in and irritate the lungs.
Next week we promise a nicer native plant!
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