| I'm posting this question on a few forums, so please excuse if you find it redundant.
Today I got positive ID for a 9-10' tall weed growing just two feet from my raised vegetable bed as being poison hemlock. I've removed the stalk and bagged it for disposal as advised by our County Extension Agent. Will have to keep after the root, since I don't want to herbicides, especially next to the garden.
One concern still haunts me, however: Since the roots are in such close proximity, will the produce from the plants in the vicinty be tainted through uptake of chemicals from the hemlock? Montana Univ. fact sheet mentioned that the toxins are most highly concentrated in the stalk base and root.
The hemlock was growing outside the retaining wall of the raised bed, which is about 8-9" high, and 24" from the tomato plants, which are now 16" high.
I hope my concern won't seem too far fetched, considering the success of companion planting, and research I'd come across years ago on how trees increase the amount of tannins in their leaves when a neighboring tree is undergoing defoliation (thus increasing their own protection against leaf-eating insects). Apparently there's some kind of (presumably chemical) "communication" going on down under the soil.
Quite an amazing plant, actually, considering it grew from a rosette only a few inches high in Feb/March - healthy, strong green leaves even in those frigid temperatures - to a 9 to 10-foot high plant today when I cut it down. I'd never seen anything like it before and wanted to ID it before destroying it ... which definitely had to be before it set seeds.
Thank you in advance for any advice or direction you can provide.
Diane | 
