Controlling Annual Bluegrass in Warm-season Fairways

Published online: Aug 15, 2017 Sod

Annual bluegrass (Poa annua) remains one of the toughest weeds to control on warm-season golf courses. Poa annua is becoming increasingly difficult to control as this weed has developed resistance to many of currently available pre-and postemergence herbicides.

Maximize cultural control – Increasing competition by the desired turf is critical to minimizing annual bluegrass:

* Maintain fertility

* Keep mowing heights as high as feasible

* Manage compaction through frequent aerification and traffic management

* Minimize soil moisture

* Minimize diseases, insects, and nematodes to limit voids where annual bluegrass can germinate

Preemergence herbicides - are most effective of the herbicides because they limit annual bluegrass at its weakest point:

* Apply prior to germination, which could begin as early as late August depending on geography

* Specticle FLO applied in the late summer/early fall should control annual bluegrass through early spring. Application rates and number of application will vary depending on your location, length of desired control, and threat of winterkill

* Ronstar Flo can be use in areas where the turf goes dormant and prior to green-up of Bermuda or zoysia in late winter to extend control of annual bluegrass and to obtain preemergence control of crabgrass and goosegrass

* Specticle Flo or Ronstar + fertilizer could be used later in the spring to further extend control of crabgrass and goosegrass

PRE/POST combinations - can also be effective and increases the number of modes of action for resistance management

* Can be applied later in the fall through the spring after annual bluegrass has germinated

* Specticle Flo + Tribute Total or Specticle Flo + Revolver can provide control until early spring

Need more info? – Find more Poa annua resources on the Talking Turf blog, or follow along on Twitter with #TalkingTurf.