Do not confuse poison ivy with imposters

Wednesday, June 1, 2016

Poison ivy is nasty, commands attention and needs to be dealt with through management practices. However, misidentifying other plants as the itch-causing agent is a common occurrence.

Perhaps one of the most commonly misidentified plants is Virginia creeper, said Dwayne Elmore, Oklahoma State University Cooperative Extension wildlife specialist.

“This vine grows throughout Oklahoma and the eastern United States. It can be found in forests and prairie edges where it is often mistaken for poison ivy,” Elmore said. “While both plants are vines, they can be readily distinguished as poison ivy has three leaflets and Virginia creeper has five.”

Virginia creeper is an important plant for many wildlife species. White-tailed deer consume the foliage of Virginia creeper, birds eat its purplish fruit during the fall and several species of birds will nest in the dense foliage the plant provides.

Incidentally, poison ivy also is an important wildlife plant despite the bane it is to humans.

“Beyond the value to wildlife, Virginia creeper is a wonderful landscape plant,” said Elmore. “It can grow in both deep shade and full sunlight, although the foliage is larger and a darker green in shaded lawns.”

During fall, it often provides a brilliant splash of color before dropping leaves for the winter. The fruit, while small, provides winter color as well, until birds consume them.

The vine can be vigorous when well watered, making the plant a good choice as a ground cover or for arbors and trellises.

“Another nice attribute is Virginia creeper is drought and heat tolerant and will grow in a wide variety of soil types,” he said. “While this plant can be found commercially, it is readily available along roadsides where it can be transplanted, assuming enough root biomass can be retained. The seeds will readily germinate as well, although it will take a few years to establish into a robust addition to your landscape.”

Another common misidentifications are of boxelder. The boxelder plant is actually a tree and looks very much like poison ivy when it is young.

“One of the big differences between boxelder and poison ivy is the arrangement of the leaves of the stem,” said Karen Hickman, professor in OSU’s Department of Natural Resource Ecology and Management. “Boxelder leaves come out at the same spot, where poison ivy and poison oak leaflets will be staggered.”

As boxelder becomes older, it will grow more leaflets and be distinguishable from poison ivy.