Poa Annua, aka annual bluegrass, is a smallish, tufted winter annual that infiltrates lawns and causes general dispair throughout the nation. Poa Annua begins the germination process in the early Fall and will begin to appear early in the Spring. This cool-season annual is one the toughest weeds to control because there is no post-emergent solution.
Pre-emergent Eradication of Poa Annua
Because annual bluegrass is tolerant of all selective post-emergent herbicides on the market, the only way to get rid of it is to stop the germination process. This can be accomplished with an application of a pre-emergent such as Prodiamine. As Poa Annua begins to emerge, Prodiamine will attack and sterilize the seed and to prevent germination. Once Poa Annua has emerged, the only option is to over-spray with a non-selective herbicide such as round up. This will take care of the Poa Annua and everything else it touchs.