I usually let broadleafs grow as it's my belief that nature grows whatever is needed to correct some type of imbalance in the soil. I just let them grow along with my food plot stuff, and try to keep them from seeding out. But in the case of knapweed it's believed to stunt the growth of other plants nearby. So I'm gping to spot spray it. Does anyone know if gly or 2-4d will work better?