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Amaranth in Food Plot?
Is there a way to get rid of Amaranth in an established brassica food plot?
Is there a way to control the Amaranth prior to planting next year?
Is it Palmer? If it's gly resistant you might try going with Liberty beans next yr.
How big is your plot? Is it small enough you could do some weed pulling by hand?
Like Cat suggested, you could plant Liberty Link beans or better yet, Enlist beans. Other than spot spraying or pulling by hand, I think you’re stuck with them in your brassicas this year.
The plot is about an acre. I’m not a weed expert. The app, Picture This says it Red Root Pigweed Amaranth. Gly kills it but it generally grew within and more quickly than the brassica.
If gly kills it you are in luck!!! I'd spend a few hours pulling them by hand or spot spraying. Don't let them go to seed! To be honest I don't worry too much about pigweed. We have the bad kind so a lot of sprays don't phase them, but deer do like them and I do my plot regenerative style so pigweed never really take hold much. I do see one or two occasionally but they never take over. If you are tilling your plots it might be a different story.
If there's a lot of it you could go nuclear and kill the whole plot, with the idea of planting this fall with cereal grains and clovers. You'd loose your brassicas but gain a different crop.
You have plenty of time to replant brassicas. They are cheap, and easy to grow. If your pigweed is exploding I wouldn’t hesitate to nuke it with glyphosate or Liberty and broadcast fresh brassica seed right over the dying vegetation. I wouldn’t till it since that will likely just pull more pigweed seeds to the surface again. I’ve planted brassicas as late as 9/15.
Pat is right the amaranths all have tiny seeds with a thick tough coating. Their propagation strategy is for some seeds to lie dormant for months or years until the coating is damaged so they can germinate. (Vetches use a similar strategy ) Tilling will not only bring them to the surface it will activate germination by scarifying the seed coat. Clip, spray, and broadcast the brassica. We used to fight "horse nettle" in pastures that way.