Jonathan Green Lawn Weed control contains Trimec®, a herbicide that suppresses broadleaf weeds when they are actively growing. Lawn Weed Control kills hard-to-control weeds such as dandelions, clover, henbit, oxalis, wild onion and over 200 other weeds. For optimal results spread this product on a moist lawn so the weed control granules stick to the plant leaves. Use lawn weed control on all types of cool- and warm-season grasses, when you want to kill weeds but have no intention of seeding or fertilizing. For particularly difficult weeds, make a second application of Lawn Weed Control 30 days after the first application.