It is often tricky to distinguish poison ivy lookalikes from the real deal. But we’ll try to make that easy by sharing some tips and tricks for differentiating between poison ivy and several other common plants.
Just remember to check out our comprehensive poison ivy ID guide: What Does Poison Ivy Look Like?
One Quick Thing: Know Where the “Leaf” Starts
One of the most important things to note when trying to identify a leaf, plant or tree is to understand exactly where the “leaf” starts.
Failing to do so can lead to problems when trying to identify any leaf, but the potential for disaster is even greater when the leaf in question may be poison ivy.
For example, you may think you’re looking at a group of three individual leaves, but you’re actually looking at three leaflets that combine to form a compound leaf.
The former will not be poison ivy, but the latter very well may be the itch-inducing plant!
In a nutshell, the “leaf” starts at the junction with the twig.
Great, but uh, how do you tell whether you’re looking at a twig or a rachis (the “stem” of a compound leaf)?
Generally, the easiest thing to do is to look for a bud at this junction. But buds aren’t always visible — especially during the early spring.
Don’t worry — there are a few other clues you can consider to determine whether you’re looking at a simple leaf or a compound leaf.
Just check out our infographic to learn a few tips and tricks for distinguishing simple and compound leaves!
You can also read more about the differences between simple and compound leaves in this article from TreeHugger.com.
Poison Ivy vs Lookalikes: Comparing Poison Ivy with Similar-Looking Plants
There are a number of plants and trees that resemble poison ivy — known to botanists as Toxicodendron radicans.
But the five discussed below probably cause more confusion than the rest. Familiarize yourself with them so you know what’s what on the trail.
1. Blackberry
Blackberries (Rubus spp.) and their relatives typically produce leaves consisting of five or seven leaflets, which means they’re rarely confused with poison ivy’s trifoliate leaves, which bear three leaflets.
However, young leaves and those emerging from lateral meristems sometimes bear only three leaflets. And confusion is common in these situations.
However, there are two pretty simple criteria by which you can distinguish blackberry from poison ivy:
- Look at several different leaves. Any large, mature blackberry plant is sure to have plenty of leaves bearing five or seven leaflets. By contrast, poison ivy will always (save for the occasional mutant) have leaflets grouped in threes.
- Look for thorns. This is the easiest way to distinguish blackberry from poison ivy; the former has thorns, the latter does not. Thornless cultivars have been developed, but you’re unlikely to encounter these in a natural habitat.
Unfortunately, blackberry and poison ivy often grow in relatively similar habitats — sun-drenched forest clearings and edges. They’re also both common in disturbed habitats, including parking lots near parks, roadside areas, and backyards.
2. Ash-Leaf Maple
The ash-leaf maple (Acer negundo) is a pretty unusual member of the maple-tree clade. Unlike most other maples, which produce leaves looking more-or-less like the one adorning the Canadian flag, ash-leaf maples produce bipinnately compound leaves, which are more reminiscent of ash (Fraxinus spp.) or hickory trees (Carya spp.).
And wouldn’t ya know it, some of these leaves bear only three leaflets (others bear five). And this, friends, can make the tree easy to mistake for poison ivy.
However, there is a pretty easy way to distinguish ash-leaf maples (which are also known as box elders) from poison ivy. Just look at the leaf arrangement — ash-leaf maples have leaves paired in opposite fashion, while poison ivy leaves are attached to the stem in alternating fashion.
Another way to think about it is that ash-leaf maple leaves occur in pairs, while poison ivy leaves burst from the stem individually.
Of course, ash-leaf maples also reach proper tree-like proportions, while poison ivy will never exceed “shrub” status.
3. Kudzu
The infamous colonizer of disturbed fields, parks, and some natural forest edges, kudzu (Pueraria spp.) is an invasive plant, which was first brought to the new world in the late 19th century. Currently, it’s found across much of the eastern United States, and it’s even been spotted in portions of Canada.
Volumes have been written about the ecological damage kudzu is causing, but we’re focusing on a different issue today: It looks just like poison ivy in some cases.
In fact, this may be the trickiest species for novice nature lovers to distinguish from poison ivy. The best way to do so is by looking for dense hairs on the stems of new growth. If you see dense hairs, you’re looking at kudzu; if you see smooth, hair-free stems, you’re likely looking at poison ivy.
Just be careful while getting this up-close-and-personal to an unidentified plant.
4. Virginia Creeper
Perhaps the most similar to poison ivy in terms of growth habit and general lifestyle, Virginia creeper (Parthenocissus quinquefolia) is another plant outdoor enthusiasts often confuse with poison ivy.
Like it’s skin-irritating lookalike, Virginia creeper often grows as a tree-climbing or ground-covering vine. It also grows in the same kinds of places that poison ivy does — the two are commonly found growing up the same tree in side-by-side or even intertwined fashion.
But it’s easy to distinguish the two when the leaves are visible: Poison ivy has leaves bearing three leaflets; Virginia creeper has leaves bearing five leaflets.
But if the leaves aren’t visible, you can note the vines. Poison ivy is covered in dense, “hair-like” roots, while Virginia creeper’s roots are thicker and they end in a small disc.
If you are lucky enough to encounter a mature plant in the fall, you can also note the fruit, which are typically white or nearly so in the case of poison ivy. The fruit of Virginia creeper plants are blue to purple.
5. English Ivy
Admittedly, this species is much easier to distinguish from poison ivy than the others listed here. But true nature newbies are occasionally confused by English ivy (Hedera helix).
At any rate, all you need to do to distinguish this leaf from poison ivy is to, you know, look at it.
Poison ivy has compound leaves with three leaflets per leaf. English ivy has simple leaves. They may be lobed, but they’re always attacked singly to the stem.
Large vines also provide identification clues, as the aerial rootlets that help English ivy cling to trees are much shorter and thicker than the hair-like rootlets of poison ivy.
Poison Ivy Comparison Infographic
Hopefully, you now feel comfortable distinguishing poison ivy from some of the plants that people most commonly confuse it with. But to make it even easier, we’ve put together a comparison infographic for handy reference.
Feel free to print it out and stick it on the fridge, save it to your phone, or share it (we simply ask that you give us credit or tag us).
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A few of the plants above are clearly pretty easy to distinguish from poison ivy, but ash-leaf maple and kudzu can be fairly tricky at times. Hopefully, we’ve made things a little easier on you in this guide.
But we’re always eager to hear other helpful tips and tricks that help people tell whether they’re looking at poison ivy or some other plant. So, have at it! Let us know how you distinguish poison ivy from some of its lookalikes in the comments below!
