Prime Source Meso 4SC Select contains the same active ingredient as the popular Tenacity Herbicide. Meso 4SC is a unique herbicide formulated for both post and pre-emergence and controls over forty-five broadleaf weed species and grasses in turf grass. This herbicide represses photosynthesis in susceptible and receptive plants as it is absorbed systemically through roots, leaves, and shoots. It can be effectively used against weed invasion and also promotes excellent control of tough-to-control weeds before and during seeding of particular types of turf grasses. This formula can be employed anytime during seeding including over seeding of established turf grass, during renovation, or bare ground seeding. Weeds are expected to die and wither within 3 weeks from the application, turning the weeds white in color due to the loss of chlorophyll. Whitening of the turf grass is common but temporary and typically occurs between 5 to 7 days after application and may last for several works. This product comes in an 8-ounce bottle.