I have a plant at our new home which I initially thought was rhubarb, but it...

Asked July 12, 2014, 8:02 PM EDT

I have a plant at our new home which I initially thought was rhubarb, but it has since sprouted very tall stalks . I was going to cut it down, but a neighbor recommended that I ask if it was a dangerous plant. She had heard that a new invasive weed has been popping up that is quite dangerous. Are you able to help from this picture? Thank you very much!

Washington County Minnesota invasive species horticulture

3 Responses

Thank you for your question and the picture. Could you take another closer picture of the leaves both at the bottom where they are mature and the top where they re immature. Also a picture of a branch so I can see how the leaves are coming out of the branch? Thanks again

Thank you so much for such a quick response! Here are the additional pictures

It looks like you have two different weeds there; neither is the giant hogweed your neighbor told you about (see http://www.dnr.state.mn.us/invasives/terrestrialplants/gianthogweed.html and http://www.extension.org/pages/70838/giant-hogweed#.U8k0eY1dWQg) They are also not Cow parsnip (Heracleum lanatum), which is a common plant that looks very similar to the giant hogweed, but does not contain the same damaging chemical.

The bottom plant, which looks very much like fuzzy rhubarb, is burdock (http://www.extension.umn.edu/garden/diagnose/weed/broadleaf/basal/cburdock.html). You can pull it out or treat it with glyphosate (Round-up is one brand). Burdock is not poisonous. In fact, it has been used for centuries in herbal medicines. It is a biennial, meaning it forms a shorter plant the first year and then comes back with a flower the next. The flower brings lots of seeds that spread the plant rather aggressively. I get burdock in my yard and pull it before it has time to flower. I wear gloves when doing so, but the plant does not have anything in it that would cause contact dermatitis like the hogweed. I am not sure what the other weed is, but recognize it as something I also get. I would pull it right away because it looks like it is setting seeds.

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