3. Foramsulfuron (Revolver) - Apply to emerged goosegrass plants in the late spring or early summer. Repeat the application in 7 to 14 days.  For the highest level of control, apply foramsulfuron before goosegrass plants have exceeded the 3-tiller growth stage. Revolver will not control smooth crabgrass.  DO NOT apply Revolver within 2 weeks of sprigging. The reseeding restriction for this product is 2 weeks.

 

Annual bluegrass control in overseeded bermudagrass greens

 

1. Pronamide (KERB 50WSP) - Apply to bermudagrass greens no sooner than 90 days before overseeding with a cool-season turfgrass.  Apply 1/4 to ½ inch irrigation water within 24 hours of application.  In the event that Kerb is applied closer than 90 days before overseeding, activated charcoal at a rate of 10 pounds per 1,000 sq. ft. should be applied to treated areas.  Reseed no sooner than 7 days after charcoal application.

 

2. Fenarimol (Rubigan 1AS) - Suppresses annual bluegrass.  If Poa trivialis or bentgrass is used for overseeding, then the triple application (4.0 fl. oz./1,000 sq. ft.) program should be used, with the last application no sooner than 30 days before overseeding.  Where perennial ryegrass is used, use the double application (6.0 fl. oz./1,000 sq. ft.), with the last application 14 days before overseeding.  A single application of 2.0 fl. oz./1,000 sq. ft. in January or early February will help to extend the length of annual bluegrass control.

 

3. Foramsulfuron (Revolver) - Apply foramsulfuron for the control of emerged annual bluegrass two weeks before overseeding bermudagrass with perennial ryegrass.  Revolver is rainfast within 2 hours of application. Revolver must be allowed to dry on bermudagrass foliage before traffic is allowed through treated areas.  Revolver is NOT recommended for use on creeping bentgrass greens.

 

4. Rimsulfuron (TranXit) - May be used to control annual bluegrass before overseeding bermudagrass with perennial ryegrass or Poa trivialis and to control annual bluegrass in non-overseeded bermudagrass. Add a nonionic surfactant at 0.25% v/v.  Apply 10 to 14 days in late summer or early fall before overseeding bermudagrass.  DO NOT apply after overseeding, or to bentgrass putting greens.  Irrigate within 2 hours of a TranXit application and then follow normal irrigation schedule.  TranXit is NOT recommended for use on creeping bentgrass putting greens.

 

Creeping Bentgrass putting greens.

 

Preemergence options for crabgrass and goosegrass control.

 

1. Bensulide (Bensumec 4LF, Betasan 4E, Pre-San 7G) - Studies have shown that bensulide will provide high levels of crabgrass control.  However, in the southern United States, bensulide does not usually provide acceptable levels of goosegrass control.  use rates range from 7.5 to 12.5 lbs. ai/acre.  Irrigate with ½ inch of water immediately after application for best results.  Reseeding restriction is 4 months after application.

2. Bensulide + oxadiazon (Andersons Goosegrass/Crabgrass Control) - A good product for both crabgrass and goosegrass control.  Apply to dry turf and irrigate-in with ½ inch of water.  This product may cause thinning and discoloration of creeping bentgrass  Delay reseeding for 5 months after treatment.

 

Postemergence options for crabgrass and goosegrass control.

 

1. Basically there are none.  MSMA/DSMA is extremely risky to use on creeping bentgrass putting greens.  Considerable research as been conducted on the use of fenoxaprop (Acclaim Extra) for crabgrass and goosegrass control on creeping bentgrass greens.  The bottom line is that this herbicide can severely injure creeping bentgrass at rates needed to control crabgrass and goosegrass.  The use of a preemergence herbicide for crabgrass and goosegrass control on bentgrass greens is recommended.  Otherwise, “hand-picking” will be necessary.

 

Annual bluegrass control in creeping bentgrass greens.

 

The golf course community has a strong need for a “sure-fire” herbicide that will control annual bluegrass on creeping bentgrass putting greens.  While progress has been made, annual bluegrass remains a very difficult weed to control.  Options include preemergence herbicides such as bensulide and plant growth regulators.  In Georgia, bensulide has not provided good control of annual bluegrass in research plots.  Probably the best option for managing annual bluegrass on creeping bentgrass putting greens is the use of paclobutrazol (Trimmit).  The label recommends spring applications after bentgrass has resumed active growth.  Use rates range from 6.4 (0.1 lbs. ai/acre) to 16.0 (0.25 lbs. ai/acre) fl. oz. per acre.  On bentgrass greens the use of a non-burning nitrogen fertilizer at 0.25 to 0.5 lbs. per 1,000 sq. ft. is recommended as a tank mix. Apply 0.25 inch of irrigation water within 24 hours of application.  Growth regulation of annual bluegrass will occur in 1 to 2 weeks and last for approximately 3 to 8 weeks.  Research conducted in Georgia showed that repeat applications of paclobutrazol would also gradually reduce perennial Poa annua spp. reptans infestation in ’Penncross’ bentgrass.  This program consisted of applying paclobutrazol at 0.5 lbs. ai/acre in mid-March and mid-April, followed by 0.25 lbs. ai/acre in mid-May; followed by 0.38 lbs. ai/acre in early October and early November, followed by 0.25 lbs. ai/acre in early December.  After 2 consecutive years of use, perennial Poa populations were reduced by approximately 60%.  Creeping bentgrass can be injured by these high rates of paclobutrazol.  The maximum creeping bentgrass injury observed from this program was 28% at 13 days following the October applications.

 

 NOTE: PACLOBUTRAZOL IS NOT LABELED FOR USE ON CREEPING BENTGRASS PUTTING GREENS AT RATES ABOVE 0.25 LBS. AI/ACRE.  THE DATA SHOWN ABOVE REFLECTS THE RESULTS OBTAINED IN RESEARCH PLOTS, AND DOES NOT CONSTITUTE A RECOMMENDATION OF THIS PRODUCT AT THE RATES DISCUSSED.