Question Well, despite using both kinds of beneficial nematodes (for both masked chafer and Japanese) in 2012 to keep grub worms disabled, they did damage about 15-20% of our San Augustine lawn in August. What do we do in 2013? I don't like chemicals, but......
Both nematodes and Milky Spore disease are very effective against these beetles but they can be difficult to use correctly and hence are prone to application errors. The standard insecticide treatment for lawns is imidacloprid (Merit) (see http://www.livingwithbugs.com/white_grub.html for control options and follow the link to Merit Insecticide info). Merit has been implicated in Colony Collapse in honey bees so be sure to follow label instructions carefully. Post a follow up if you have questions.
I can answer questions in any area of entomology (study of insects, spiders, mites, ticks, and other terrestrial arthropods). Contact me about home and garden insects such as aphids and spider mites, insects that bite and sting such as ticks and wasps, and insects that damage homes such as carpenter ants and termites.
20 years as university extension entomologist, now retired; currently publish a website about home and garden insects.
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Fine Gardening magazine
Education/Credentials Ph.D. in Entomology (the study of insects)
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