How can you control Poa Annua (Annual Bluegrass)?
The most important treatment is the application of pre-emergence before we hit nighttime temperature at 70 degree or lower for three nights in a row. After that Poa Annua will began to germinate. This will usually occur in Atlanta about mid September, maybe a little soon in Northern suburbs. Even though the Poa Annua has germinated, you can not see it. In November/December, application of Simazine will help control any Poa Annua that has already germinated. Simazine will kill any recently germinating Poa Annua, and it will add an additional level of pre-emgerence. One problem is that Poa Annua can sometimes build a resistance to Simazine. As early spring arrives, there are several post-emergent chemicals that can handle Poa Annua. The key is to identify Poa Annua early and to treat immediately.