What are these and how does someone get rid of them? My mom's flowerbeds are infested with these things (the thistles) and she doesn't know what to do. She has tried Round Up on them and they just seem to come back heavier the next year. Any other ideas out there? TIA!
Are they near a birdfeeder? I don't know if they're the same kind of thistles that are in the thistle seed mix, but that would explain them coming back every year even after she hits them with Roundup.
I don't think she has a bird feeder, but I will ask. Anything else out there stronger than RU that you don't have to have a business license for?
http://en.wikipedia.org/wiki/Guizotia_abyssinica
http://davesgarden.com/guides/pf/go/139810/
The so-called "thistle" for bird seed isn't really a thistle. (Not that birds wouldn't have deposited the seeds for those weed thistles.) I guess I shouldn't be surprised to find it listed in plantfiles!
Sorry, no advice about the real thistles. I dig the same one up every year.
So, if a person wanted to remove all the soil from their bed to try to get rid of any roots, how far down do you think they should dig?
Deeper than I can say...I really thought I got the one big one last year, and I dug a foot or so. But it's back.
That's kinda what I figured. I'm thinking she should dig it out and then use Preen on the new soil?
I had similar thistles in an Oriental Poppy bed in Ohio. I think that they were dormant or not noticeable, or small when I put the poppies in. I had gotten the poppies from another person's yard and probably brought the thistles with me in their soil. I was trying to get every bit of their soil that I could so the poppies would survive. I was kind of dense when they started up the next spring. I was extra happy with the showing of so much poppy foliage. Then it hit me about the two different leaf shapes and the one plant was not prickly like the other plants. I had a huge awakening I can tell you that. I tried to eliminate the thistles, but could not do so. Both of them got stronger, larger, grew together, and made it miserable for me!
Karin ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
That does sound miserable, Karin!! I don't think I want to tell my mom your story though....that would be way too depressing for her! lol
The Preen will work to prevent new seedlings from coming up, but if these guys are coming back every year from the roots it won't do anything for that. I don't have this type of thistle, but I've had some luck with cutting things like this off at the base, then immediately spraying the wound with Roundup, I think that helps the RU get all the way into the root better than it would if you spray it on the leaves. But I think my thistles here are mostly annuals so they're not as tough to get rid of.
Well, my mom sprayed RU on the thistles and let them sit for 2 weeks. It actually killed them this time and she cleaned them out and planted some flowers. Thought I would show it off.
