SureGuardĀ® SC Herbicide delivers the longest pre-emerge residual control of grass and broadleaf weeds - often 8 months or more. Weeds prevented include Barnyardgrass Bittercress Bluegrass Chickweed Crabgrass Dandelion Field pennycress Foxtail Goosegrass Groundsel Lambsquarters Morningglory Nightshade Pigweed Pineapple-weed Ragweed Russian thistle Shepherd's-purse Spurge AQUATIC WEEDS Alligator weed Duckweed Frog's bit Water fern Water lettuce Watermeal.