For gardeners, weeds are an unavoidable nuisance.

But have you ever heard of a weed that can fight back and hurt you?

The giant hogweed plant can grow anywhere from eight to 16 feet high and it looks like a giant Queen Anne's Lace.

The Pennsylvania Department of Agriculture is worried that they've made their way into Mercer County.

What makes it so dangerous? It's sap. Sunlight exposure after contact with the sap will result in blisters.

You'll then get a burn that will last for weeks and scaring lasting for several years.

"And you'll then have a sensitivity to light and that's what causes the issues. It is dangerous if you get it in your eye. You could get temporary of permanent blindness from it," said Penn State University Master Gardener Coordinator, Susan Lanigan.

So don't go using your weedwacker on this weed.

One of the most identifiable features is the purple color of the stem and coarse white hairs on the stem as well. The leaves can grow up to five feet across.
The plant likes to grow in wet areas.

There are some plants out there that look similar to giant hogweed and they are kind of cousins; cow parsnip and Angelica. Hogweed has a thicker stem and although the flowers are similar, they aren't tall enough.

 If you find it you can call Pennsylvania and Ohio's plant pest control hotlines (PA 877-464-9333. OHIO 614-728-6400.)