Parthenium Species, Congress Weed, False Ragweed, Santa Maria Feverfew, White Top Weed

This plant moved in when our yard changed due to oak wilt loss. We didn't like it and kept pulling it up, but it's persistent. I've had t...Read Moreerrible problems with an allergic rash for the past three years. I put on gloves and long sleeves a few days ago to pull a bunch that was flowering. Terrible reaction, as bad as rolling around in poison ivy. I wonder if this is the root cause of my allergy problems? I don't know if everyone is sensitive to it like this, but I think I'm going to use an herbicide for the first time in my life. Do not plant this in your yard!

Definitely do not plant Ragweed parthenium see UF/IFAS/Extension publication ...Read Moretarget="_dgnew"rel="nofollow">http://edis.ifas.ufl.edu/pdffiles/EP/EP44800.pdf
This is invasive worldwide!
There seems to be a lot of confusion with Baby's Breath
Gypsophila paniculata L. which may also be invasive.
We have entire vegetable growing fields that fill up with white top, remain untended until fall and spread this weed even more which causes additional use of herbicides!

This plant is growing in shade in my garden. I did not plant it, just found it one day. I love the flowers and the foliage is a deep green.

This plant is growing like mad in an area of my horse pasture, and one of my donkeys was chowing down on it, which is what led me to want...Read More to find out what it is (and if it was poisonous or not). Like the other poster, it took FOREVER to figure out what this was. My sister and I have been searching online off and on for two days now!

Today we finally were able to narrow down to a hunch that it was in the Asteraceae family, then we found a site that listed the Parthenium genus plants. Voila, we saw a photo of False Ragweed, but the photo wasn't very good. FINALLY, we did a search and found it was listed here on Dave's.

Thank heavens for this site. It was beginning to drive us nuts!
Thank you everyone who posted pictures of it, too!

For us, we had no allergic reactions. We have been handling them quite a bit these last few days, so if we were going to we'd be in pretty bad shape as much as we've handled and sniffed, etc.

I'm wondering if perhaps the Texas variety is not as noxious as the ones elsewhere...?

I'm in Spicewood btw. I think my membership here says Brownwood, but I've moved. Spicewood, TX is outside of Austin.