I’ve noticed a lot of poison ivy this spring. We get lots of questions at the N.C. Cooperative Extension, Caldwell Center throughout the year about poison ivy identification and control. I thought I’d get ahead of the questions and give details on identification and control.

Poison Ivy in its native habitat. The small white flowers will become yellow white berries in the fall. (credit: Seth Nagy)

Everyone has heard the saying “Leaves of three, let it be”. That saying is a good first step to identifying poison ivy because its leaf is made up of three leaflets. Poison ivy leaflets are two to four inches long with pointed tips. The leaves can be dull or glossy. Of the three leaflets, the middle one is generally larger than the two outside leaflets. The leaf margins or edges tend to be variable in that they can be toothed, lobed, or smooth. Poison ivy is often confused with Virginia creeper vine. The easiest way to tell the difference between poison ivy and Virginia creeper is the number of leaflets. Poison ivy has three and Virginia creeper has five leaflets.

Poison ivy can be shrub-like or vine-like. Poison ivy typically grows like a vine when trees or other objects are available to provide support for the vine. The vine has aerial roots on the stems that give it a “fuzzy rope” appearance. In the fall, poison ivy leaves turn an attractive red or reddish yellow color and produce clusters of waxy, berry-like fruit.

My colleague, Matt Jones, created a great 4 minute video that will make anyone an expert at identifying poison ivy. Catch the video at go.ncsu.edu/poisonivy.

Control options are similar to other weeds and vines. Mowing, hand pulling, or using a weed eater are all good options unless you are allergic to poison ivy. The allergic part comes from the urushiol oils that are in all parts of the plant. As a side note, if you are allergic and you think you’ve been exposed to poison ivy, wash with a heavy duty dish detergent like Dawn. This will wash the oils from your skin.

Another control option is grazing animals. Goats, sheep, and cattle will all preferentially graze poison ivy. Animals will select it and graze it before consuming most other forages. Poison ivy will not survive if grazing animals can reach the leaves. It is interesting to note that grazing animals, as well as animals in general, are not allergic to poison ivy.

Herbicides are typically the most popular option for homeowners. The pesticide label indicates where the product can be applied and what restrictions or caution the applicator should take when applying the product. Pesticide labels have lots of good information. It is worth investing a few minutes before you make an application to best understand how the product should be used. One herbicide option is a product with the active ingredient glyphosate. Glyphosate was originally marketed by Monsanto as “RoundUp”. This product is now marketed by many companies under many brand names.

Glyphosate is a non-selective herbicide that is an appropriate choice in the home landscape and most other locations. This product can be applied as a spray, or it can be applied with a wiper or sponge directly to the foliage. A wiper application uses a concentrated solution of glyphosate and is applied or “painted” onto the leaf surface of the plant to be controlled. There are directions on the glyphosate label on how to make a wiper application.

Another option is a herbicide cocktail with the active ingredients of triclopry and 2,4-D. This selective herbicide was originally marketed by Dow AgroSciences as Crossbow. This herbicide can now be found marketed by many companies under many brand names. Ortho was the first company to offer the active ingredient triclopry in a homeowner version called “Poison Ivy and Brush Killer”. Triclopry is a very good brush killer that will control poison ivy. This product can also be applied as a spray or as a wiper application.

If you have agricultural questions, visit us anytime at caldwell.ces.ncsu.edu or contact us during normal business hours at the N.C. Extension, Caldwell Center at 828-757-1290.

IMG_20180515_063453713.jpg – Poison Ivy in its native habitat. The small white flowers will become yellow white berries in the fall. (credit: Seth Nagy)

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Seth Nagy is the Caldwell County Cooperative Extension director. The Caldwell County Cooperative Extension Center, 120 Hospital Ave., #1 in Lenoir, provides access to resources of N.C. State University and N.C. A&T State University through educational programs and publications.