[Image: poa]It won’t be long before annual bluegrass (Poa annua) starts germinating in Louisiana and Mississippi. Annual bluegrass is characterized by its pale green color, heavy seed production and an affinity for golf course turf.
Seed germination is stimulated by daytime temperatures in the 70s, nighttime temperatures in the 50s and high light intensities. Poa becomes most noticeable from mid to late winter through spring because of the weed’s unsightly seed heads. Seeds are easily tracked onto greens by players' shoes and turf maintenance equipment.
Poa prefers damp, compacted soils; therefore, practices that reduce soil compaction and promote drainage reduce weed infestations. That being said, Poa infestations are usually combated with herbicides. Several options exist with preemergence herbicides applied in the early fall on golf courses that will not be overseeded; however, most of these herbicides are not labeled for bermudagrass golf greens. Below is a quick table of preemergence herbicides that can be used on non-overseeded greens. Consult label for specific application information and precautions.
|
PRE Herbicide for Poa control on non-overseeded greens |
Rate in Pounds
Active Ingredient /Acre |
Comments |
|
Bensumec/Pre-San |
7.5 to 12.5 |
Apply irrigation soon after treatment |
|
Kerb T/O |
0.5 to 1.0 |
Restricted-use herbicide – has both pre and post activity |
|
Anderson’s Goosegrass/Crabgrass Control |
7.5 |
Can injure greens – Expect yellowing |
Over the past few years, several herbicides with the acetolactate synthase inhibitor mode of action have been released for postemergence control of Poa on golf courses. TranXit and Revolver may be applied on greens. TranXit, Revolver and Certainty may fit when applied a specific number of days before overseeding (see table below for application timings). Here is a list of “newer” herbicides labeled for postemergence annual bluegrass control. Remember: Do not apply these products to overseeded turf. To maintain Poa control in overseeded turf, you must have a thick overseed cover to keep the Poa out. On non-overseeded turf, you may have follow-up treatments as needed to maintain a Poa-free turf. Consult label for specific application information and restrictions.
|
Herbicide |
Rate in product/Acre |
Days before overseeding |
Labeled for Greens |
|
Certainty |
1.5 to 2.0 oz |
7 to 10 |
no |
|
Monument |
0.33 to 0.56 oz |
42 |
no |
|
Revolver |
4.4 to 17.4 fluid oz |
14 days |
yes |
|
TranXit |
2.0 oz |
14 days |
yes |