Can Poa annua and Barricade co-exist?

Effective pre-emerge herbicides such as Barricade (prodiamine) are usually used to prevent infestations of crabgrass, poa and other weeds. So why, you may wonder, are we worrying about whether Barricade and poa can co-exist?

The reasons for our concern come our observation that in mixed turf situations, Poa annua is frequently a significant component — sometimes more significant than anyone realizes. We have recently encountered a few situations where applications of Barricade made several months earlier had unexpected, and undesirable…