Ethofumesate 4SC Select – Compare to Poa Constrictor®Overview Ethofumesate 4SC Select is a selective turf herbicide labeled for control of Poa annua (annual bluegrass) and other grassy weeds in established turfgrass. This formulation contains 42. 0% ethofumesate and is designed for use on labeled cool season turf species. Comparable to Poa Constrictor and Prograss based on matching active ingredient and concentration, Ethofumesate 4SC Select delivers professional grade annual bluegrass suppression and