WHITE GRUB CONTROL IN LAWNS
One of the major pests in lawns is the white grub, it occurs in most areas of Texas, but may cause damage only in certain areas. The adult form of the white grub is often called the June beetle and is about ½ to 5/8 inches long and light brown. The flight period for the adults in the High Plains generally occurs from mid-to-late June and lasts from one to two weeks. It is during this time the mating takes place. The mated female bores back into the earth and begins laying between 30-40 eggs which hatch in three to four weeks giving rise to small larvae or grubs.
The larvae pass through three stages becoming larger with each successive stage as they feed voraciously on grass roots. Stages 1 and 2 only require about three weeks for development while stage 3 is in the soil for the rest of the year or two years and causes most of the lawn damage. Feeding of large number of the larvae causes lawns to turn yellow in the affected area.. Positive identification of white grub damage is possible when yellowed grass can be lifted easily by hand from the ground. In severe infestations, large section of lawns can be rolled up just like a carpet. The stage 3 larvae build up large quantities of fat in the summer and fall and may not need to feed further during the remainder of the annual cycle.
Lawns suspected of having white grubs should be checked by cutting and digging up one square foot section of lawn four inches deep and examining. Treatment is justified when more than four grubs per square foot are found. Many products provide adequate control when applied properly. Merit or Grubex are two products that can be applied from late July through mid September. During this time the grubs are quite small, just beginning to feed on your lawn and are easier to control. Waiting until next spring to treat is too late. The damage to your lawn has already been done.
Granular formulations of insecticides are easier to apply and easier to wash into the soil than spray formulations. Granulars may be applied with a fertilizer spreader. If spray formulations are used, water the lawn with about one-quarter inch of water before applying the spray. This allows the spray formulation to better penetrate the soil.
Insecticides should be washed into the soil immediately with one-half to one inch of water. Children, pets and other animals should be kept off the lawn until the insecticide has been thoroughly washed into the soil.
Always use insecticides according to the directions on the label. Proper lawn care is important in the reduction of home owners’ grub problems. Adequate water and fertilizer and annual dethatching produces a healthy, vigorous lawn that is less susceptible to damage by white grubs.
