By: Frank S. Rossi, Ph.D. (September 15th ShortCUTT)
The last month has been very dry and on the cool side. Those with a functional irrigation system are enjoying the lack of other stresses, beyond traffic stress related to unabated golf for more than a month with limited rainfall.
Chinch bugs can still be active on cool-season turf this time of year, especially during warm, dry spells when grass might be drought stressed. They feed at the base of plants by sucking sap and injecting toxins, which causes patches of turf to yellow and thin, often resembling drought stress. To scout, part the grass at the soil surface near damaged areas and look for small, black-and-white nymphs or adults moving quickly. Control includes targeted insecticide applications. Regular monitoring is important, since chinch bug damage can persist until cooler, wetter weather slows their activity.
Crabgrass naturally declines at this time of year and will be killed by the first frost in a few weeks, but the thousands of seeds it drops will fuel next year’s infestations. At this time of year, control is limited—hand removal or mowing before seed heads mature can reduce seed return—but it’s also a good opportunity to identify thin or infested areas where additional pre-emergence herbicide applications should be targeted next spring. Maintaining dense, healthy cool-season turf through fall fertilization before mid October, and overseeding remains the best long-term strategy to outcompete crabgrass.