Rush is the only Kentucky bluegrass variety bred specifically for competitiveness with Poa annua, particularly under close, fairway-height mowing. Rush was tested as experimental J-2222 and is an elite hybrid of BlueChip Kentucky bluegrass.

Dr. Doug Brede, breeder of Rush, remarks that it's the most Poa-resistant bluegrass he's ever seen: "In our 2000- 2006 Idaho turf trial, Poa annua overtook the close mowed plots. Only a handful of Kentucky bluegrasses resisted the Poa invasion. Of the 3000 commercial and experimental varieties in that trial, Rush did the best."

.