Field Note: Common Lambsquarters Management

This week’s weed, Common Lambsquarters, can be a difficult to control in corn and soybean rotations because of its early emergence and competitiveness. Of course, if not controlled, you can always utilize it to replace your spinach in your salad as it is edible and very nutritious! Now back to controlling this tough weed.

Corn offers effective control of Common Lambsquarters through starting clean and utilizing products with soil applied residual. Keystone® LA NXT contains acetochlor and is effective at stopping small seeded broadleaf emergence. Start clean by applying a burn down application of 2,4-D or dicamba to corn fields or utilizing tillage to remove small weeds. Larger sized common lambsquarters can be tough to remove utilizing tillage, sometimes requiring an application of a burn down herbicide even after a tillage pass. Post applications of products like Resicore® and Atrazine® are extremely effective against common lambsquarters.

Soybeans, once again, give us the biggest issue when controlling this broadleaf weed, especially in no-till systems. As always, start clean with a burn down of 2,4-D or FeXapan® in RR2 Xtend® soybeans. The addition of a herbicide containing FirstRate such as Sonic® can be very effective. Fomesafen, found in common soybean herbicides Reflex® and Flexstar® is generally ineffective due to its thick waxy cuticle. Other residual herbicide options for pre-emergence include Authority® MTZ, Enlite®, and Valor®. Glyphosate can be effectively utilized as post control, and though not 100 percent effective is a valuable tool. FeXapan® in RR2 Xtend® soybeans is effective as well. Herbicide systems involving gluphosinate can be effective, but rates should be increased as common lambsquarters height increases.

The main lesson with this week’s problem weed is to start clean. Otherwise you may need to start eating a lot more salads!