Summer is in full swing and temperatures are forecasted to hit 100 F this week in parts of the Mid-Continent region.
We have two particularly difficult pests that started in the spring and continue to persist - bermudagrass mites and nematodes. Both are difficult to control as the most effective control products are no longer on the market.
Bermudagrass mite damage has been termed “witch’s broom” because of the stunted, branch-type growth from the plant’s nodes. A yellowing of the turf is also prevalent in infected areas. Mites have been active on the ultradwarf bermudagrasses as well but with different symptoms. Instead of the “witch’s broom” effect, stolons tend to grow over the top of the playing surface. Brushing removes them quite well.
Treatment has been successful with a few materials, but a second application is needed in 14 days to break the egg cycle. In the days of Diazinon and Dursban, mite damage could be minimalized, but now companies are in search of better controls. Soluble nitrogen is most helpful to encourage growth and recovery from damage.
Unfortunately, the nematode battle has been more difficult. There are materials available that have shown some success but universities and chemical companies continue to search for products with greater efficacy. A word of caution – there are several materials that claim nematode control but have been unsuccessful in research trials. Ask for data confirming control claims. The industry is hoping for a control product as effective as Nemacur, but the hunt continues. The University of Florida is a great resource for the latest in product testing and results.
Source: Bud White (budwhite@usga.org)
Information on the USGA’s Turf Advisory Service
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