White Grubs

These short, fat, soil inhabiting white worms can cause severe damage to all of the varieties of lawn grasses found in our area. Although open, sunny lawns are the most likely to attract this pest, partially shaded areas have been exhibiting more damage in recent years.

The cause of this problem is the larval stage of a particular 'June Bug' whose life cycle is completed in one year. The adults are small, brown beetles that appear during the evenings in June and early July. Since the adults are attracted to light, they often converge on porch lights, patio lights or uncovered windows. You may hear them bumping into the glass panes of storm doors or windows as they seek the light source. In our area the peak of the adult activity usually occurs around the first week of July.

After mating, the female beetle flies over a lawn, selects the 'right' spot and deposits her eggs in the soil. Depending on soil conditions, these eggs hatch from late July through August. As they begin feeding on the roots of grass plants, the 'baby' grubs grow rapidly in size. Most damage becomes obvious during August and September when the full-sized grubs are feeding to store up reserves for winter survival. As the soil temperature drops during the fall, the grubs move deeper into the soil to wait out the winter below the frost line.
The following Spring brings rising soil temperatures; the grubs return to the root zone, feed briefly (causing very little, if any, additional damage), pupate and emerge as adult beetles in June to begin a new cycle.

Some nocturnal animals like skunks, opossum, etc, love to feed on grubs and will cause significant damage to lawns as they rip up the turf to get at the grubs. Moles, which feed on soil inhabitants such as earthworms and grubs, may be attracted to areas with high grub populations.
Fortunately, the White Grub problem is easily prevented by a timely application of the appropriate control agent. The newer controls are quite effective and require only one application per year.