Landscape Alert
WHAT ARE WHITE GRUBS
What are White Grubs?
High populations of these turf-damaging insects are present in the Tri-City area. White grubs are the C-shaped larvae of many different beetles, including Japanese, May/June, Oriental, European Chafer and Masked Chafer. They feed on the fibrous roots and thatch of turf during the spring and fall months. Infestations of over six per square foot can be devastating to turf causing large brown areas of dead grass, which can be peeled back like a carpet. Other signs of grub activity include birds and animals such as skunks, opossum and raccoons searching and feeding on these grubs as they move near the surface. Moles will also feed on grubs in the soil, but keep in mind that controlling the grub problem will not necessarily rid your lawn of any animal activity.
Fully grown grub larvae are one-half to three-quarters of an inch long and can be identified by the rastral (hair) pattern found on the tip of the abdomen using a hand lens. Though life cycles may vary slightly between grub species, they generally follow these guidelines. Grubs overwinter 3 to 12 inches in the soil and as the weather and soil warms will move toward the surface and start feeding in April. Around June they pupate into adult beetles, leave the soil and begin to feed on plant material. In July they will then enter the soil and lay eggs. In mid August those eggs will hatch and begin to feed and grow near the surface. During the month of October, the grubs will begin to descend into the soil, make winter cells and prepare to emerge the following spring.
Is My Lawn At Risk?
Unfortunately, white grubs typically prefer lawns which are properly maintained through good fertilizing and watering habits because the resulting grass roots are lush and nutrient rich. Seldom are grubs found feeding on lawns that are unfertilized, unwatered, and/or extremely weedy. Lawns with excessive thatch provide an excellent breeding ground for grubs as the heavy thatch layer will prevent insecticides from reaching and killing the developing grubs in the root zone of the lawn where they feed. Prior to the application of any insecticide, thatch levels should be evaluated and, if found to be excessive, reduced through dethatching.
How Are Grubs Controlled?
Whether or not to treat for grubs is determined by population and lawn damage levels. If high populations of grubs are found and damage is present, a “contact type control” may be applied during the insect’s feeding stages in the spring and/or fall. If grub populations and damage levels are lower but determined to be a future risk, a “systemic type control” can be applied in mid-summer. These products are absorbed by the grass plant and allow the turf to protect itself by destroying grubs that begin to feed later in the season. Keep in mind, however, that no control is 100% effective. The goal is to maintain populations below levels that cause serious and/or permanent damage.
Reder Landscaping employs trained and certified lawn care specialists who can inspect your lawn, diagnose problems, make recommendations, and, if necessary, take steps to control pest problems or improve the overall health and appearance of your lawn. We are also deeply committed to the protection of our environment, which is why Reder Landscaping promotes and follows an IPM (Integrated Pest Management) approach to pest control. Because a properly maintained landscape is able to ward off damaging levels of many pests, IPM makes first use of cultural practices such as proper nutrition, watering, pruning, etc to avoid problems in the first place, using chemical controls only when necessary.
Feel free to call us today if you have questions or would like to improve the health and appearance of your lawn and landscape.