Dick Adams wrote:
Last summer and again this spring, I sprayed
Round Up on a bed of poison ivy. The stuff
came back. What should I try next?

Dick
http://www.nfpa.org/categoryList.asp?categoryID=161&
URL=Codes%20and%20Standards/Code%20development%20process

Crossbow is another one -- it's a mixture of 2,4-D and triclopyr that
may be more effective than just Roundup alone.

As another poster (and the above link) notes, poison ivy is tough
stuff--even a trace of root alive will regenerate over a summer plus you
may have seed from previous years germinating as well...it's a
multi-year project if there's any established colony at all in all
likelihood...

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