On the one hand, the reason for the decline of the various milkweed butterflies appears largely to be a result of areas that once supported some milkweed populations were hit with glyphosate which killed the host plants off at a massive scale. On the other hand this is already happening with chemicals sprayed indiscriminately, this reduces the amount that's sprayed, which could save farmers money, and this reduces glyphosate runoff which is good. Still seems to have the down side that if actually adopted would likely cause even more loss since it could be used on crops where it's avoided now. And no farmer is going to program it to skip milkweed or some other important host plants, they hate milkweed.
