martin - 8/2/2021 07:32
Butyrac is safe on alfalfa - both RR alfalfa and non-RR alfalfa. Label does not specifically have Waterhemp on it, but label does say control of pigweed, up to 3" tall. Also, I was thinking it was 30 days to harvest. However, the label I read says "do not feed straw or hay for at least 30 days after harvest". The way I read that.... is different from " do not harvest for 30 days after harvest."
I would try Butyrac and do it soon after alfalfa regrows - maybe when alfalfa is 3-4" tall. That way you will be catching the Waterhemp when it is small as well.
Butyrac label also lists a tank-mix of Butyrac and Butril as a possibility for pigweed. Rate of Butyrac would be less on the Butyrac when tank-mixing with Butril. I don't use Butril much. I don't know if this is a better way to go, than just Butyrac (and Roundup).