The Master Gardener Articles

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Grubs

This spring you many have noticed areas in your lawn which failed to green up. Upon closer inspection you may discover that the turf is very loose and rolls up like a piece of carpet. If this is the case, you have experienced a grub attack. This damage occurred last fall but was not evident till spring. The cool weather of the fall and frequent rains kept the grass green, although it had very little roots remaining. Grubs will feed on the roots of your turf, from egg hatching in late July till cool weather forces the grub deep in the soil (6 – 12”) in November. In April as the soils warm the grub will again surface up to the 1”-2” depth, feed for a short period of time, then emerge as a beetles in late May and early June, (Japanese, May and June Beetles and European chafers). For optimum insect control, apply when the grub is just starting to develop (later July). Some grub control products have up to 4-5 months residual, so time of application is less critical. A late spring application (mid June) is recommended to assure chemical penetration to the feeding zone, which is induced by late spring rains. If later applications are made, but before mid August, be sure to water in the product should summer rains not be cooperative. The fringe benefit of a good grub control program is a reduction of the mole population. Although moles live on other protein in your lawn (worms), you have reduced their food supply substantially. Hopefully they will move on to better hunting grounds.

For more information, contact George McVey, Union County Program Assistant, Horticulture and Master Gardener Coordinator at 937.644.8117 or by e-mail at gmcvey@ag.osu.edu.