Spiny amaranth in newly planted alfalfa/orchard field

Previously 20ac were row cropped with last 2 years in soybeans. I put in annual rye this spring which did well. August came around and I went to work on putting in alfalfa/orchard on 20ac and Timothy on another 10ac.

Now, the alfalfa is doing great with a little orchard poking through, but I have quite a bit of spiny amaranth in this field which apparently was previously held back with sprays and the rye. But now... how do you deal with it in a mixed pasture?

Will the alfalfa keep it in check next spring? I'm kind of at a loss on what to do right now. Or whether I should do anything.

I thought about a wiper, but I've read it is hard to kill bigger than 6".

I planted a strip around the outside which will be bluegrass/orchard, just for something to mow and keep clean around the fences (when they are built). It's why the edge isn't filled in yet.



Spiny amaranth in newly planted alfalfa/orchard field