Is it? Could it be . . . Poison Ivy?

– Posted in: Fruit, Native/Invasive, Pests, Plagues, and Varmints, Plant info

It was April. I had just come back from a cabin-fever-induced tramp over our field and through our woods. I had noticed this red-leafed vine growing all over:Red foliage of mystery vineIf our field is 5 acres, then this was easily growing on two acres of it. It lined the main walking path and carpeted the ground near my favorite sitting spot. And then I read Judith’s post about poison ivy. Uh-oh.

It’s a vine. It has three leaves. It has the lovely red fall color that is supposed to be characteristic of poison ivy, carried through the winter into spring. (We had had rather mild winter temperatures, and not too much snow.) How could it have grown all over without my realizing it was happening?

So I fretted about the difficulties of eradication, and braced myself for the onslaught of poison ivy rashes. Well, a funny thing happened on the way through the summer. No one ever got a poison ivy rash. Not even me, when I inadvertently ripped the vine out of the ground with my bare hands, while weeding around my gooseberry bush.

And another thing. While I had seen it growing on the ground around many trees, I had never seen the vine start climbing up a tree.Stem of mystery vine And the vines have bristles on them. While looking for identification pictures on the web, I’ve never seen a photo of poison ivy with bristles.

And the fruit of poison ivy is a white berry. As my son showed me, this vine’s fruit is definitely not white. As a matter of fact, it looks a lot like a . . . blackberry. But it’s not a blackberry. Blackberries have long whip-like branches called canes. They grow upright, making bushes. The prickles are, as anyone who has picked blackberries knows, quite a bit more pronounced–and vicious. Fruit of mystery vineAnd a blackberry typically has more of those little round balls (drupelets) in one berry.

It turns out it’s a native plant called swamp or bristly dewberry (Rubus hispidus). It took me a long time to make a positive id, because there’s more than one kind of dewberry, and on some sites, the photos didn’t look quite like my plant. (In fact, I now think the largest photo on this site is not the correct plant.) And while some of the poison ivy sites I visited had a photo of blackberry brambles in their gallery of impostors, none had dewberry. It’s hard to search on the internet for something that you know what it looks like, but not what it’s called.

At last, this mother breathes a sigh of relief. Not. poison. ivy. But I sure did learn a lot. I hope you did, too.

About the Author

Kathy Purdy is a colchicum evangelist, converting unsuspecting gardeners into colchicophiles. She would be delighted to speak to your group about colchicums or other gardening topics. Kathy’s been writing since 4th grade, gardening since high school, and blogging since 2002.

What differentiates a bulb from a perennial plant is that the nourishment for the flower is stored within the bulb itself.…There is something miraculous about the way that a little grenade of dried up tissue can explode into a complete flower.

~Monty Don in The Complete Gardener pp. 142

Comments on this entry are closed.

Mary Lou September 7, 2006, 6:19 pm

WHen I saw It I immediately said Blackberries! We have what we call Railroad Track Blackberries that grow along the ground, looks just like your vine, and looks like a small blackberry. Not the round berries that you have. and they take a BUNCH to make jam with but they are soooooooo good!

Cynthia September 7, 2006, 9:17 am

I’m so glad to be getting notification of new posts again. I now remember what I’ve been missing: your insatiable appetite for knowledge and your apt ability to share it. I always steer clear of ivy-like plants for fear of a recurrence of an incredibly horrible experience with poison ivy when I was 9 years old. I would do better to just educate myself!

Jenn September 7, 2006, 7:04 am

Hah! Since we battle the ivy on a regular schedule, I guess I assume everybody gets regular robin dropped seedlings.

Good for you, to not have any ‘volunteers.’

Much as I like robins, I do wish they didn’t like the ivy berries so…

Laurie September 6, 2006, 10:57 pm

Dewberries are edible; they grew all over the back field at my parent’s house, and my brothers and I would often eat them. That said, the berries are very small, the plants are not heavy producers, you have to crawl around on the ground to find them, and they really don’t taste better than other, easier to harvest berries. Leave them for the birds. Anything that likes blackberries will like dewberries.

Carol September 6, 2006, 9:10 pm

I agree, since it’s not poison ivy, leave it. Food for the birds.

That was some good plant detective work on your part to figure out what the plant was. It is hard to find a plant online when you only have a picture. Where’s a “dichotomous key” when you need it?

Kathy Purdy September 6, 2006, 6:51 pm

Jenn–I’m not sure what you mean about steeper curve. If there’s any poison ivy on our land, I haven’t seen it. It’s all been this dewberry vine.

Kim–the various websites and books I consulted were kind of wishy-washy about human consumption. They are definitely NOT poisonous, but the flavor is described ranging from tasty to insipid. I presume wildlife of all kinds like to eat the berries, but I didn’t see a list anywhere.

There’s no way I’d pull out two acres of plants, and why would I want to? It’s a native plant, and it’s NOT poison ivy.

Kim September 6, 2006, 11:13 am

Are the dewberries edible, or do they make good bird food? Are you going to leave them where they are, or still pull the plants out?

Jenn September 6, 2006, 11:04 am

Convincing imposter!

Bristles are a good field sign. Ivy does that roots-all-over-the-stems thing, but doesn’t have bristles. I’d’ve been fooled by this guy though.

Now, however, you have a steeper curve on finding the ivy before it gets out of hand.

Ah, nature.