Goosegrass was an issue for many golf courses during the 2018 season. For some golf course superintendents, goosegrass is a familiar foe. Others are just becoming acquainted with this weed that can be found in roughs, fairways, tees and even putting greens. When it comes to goosegrass control, preemergence herbicides are extremely valuable tools.
Goosegrass will begin to germinate when soil temperatures are between 63 and 65 degrees Fahrenheit, which is several degrees higher than when crabgrass germinates. For golf facilities located in the Midwest, the time to apply a preemergence herbicide for goosegrass control is either now or it is fast approaching.
Superintendents who face goosegrass as an annual issue have found improved control by making sequential preemergence herbicide applications so both crabgrass and goosegrass are targeted. If a preemergence herbicide has already been applied this season, a sequential application can still be made provided this will not exceed the maximum amount of active ingredient that can be applied in a year.
Dithiopyr and prodiamine are common preemergence herbicides used on fairways, tees and roughs. Unfortunately, these products are not labeled for creeping bentgrass putting greens. Options for preemergence goosegrass control on creeping bentgrass putting greens are bensulide or a combination of bensulide and oxadiazon.
Excessive rainfall and high temperatures will cause the herbicide barrier to break down faster or push the product too deep into the soil for it to be effective. Should these weather conditions be experienced, scout for goosegrass emergence so a postemergence herbicide can be applied while the weeds are small. Unfortunately, there are not any postemergence herbicides labeled for goosegrass control on creeping bentgrass putting greens. Physical removal is usually the most effective method if breakthrough occurs on putting greens.
If goosegrass was an issue at your facility in 2018, it is likely to reemerge this year considering it is a prolific seed producer. Treating preventatively for goosegrass will help avoid issues with playability, as well as saving the time that would be required to physically remove goosegrass if it were to encroach on putting greens.
Central Region Agronomists:
Bob Vavrek, regional director – firstname.lastname@example.org
John Daniels, agronomist – email@example.com
Zach Nicoludis, agronomist – firstname.lastname@example.org