The Palisade Colorado Japanese Beetle Eradication Program

NEWS RELEASE - May 19, 2004

IMMEDIATE RELEASE

Help control Japanese beetle by proper lawn watering.

The Palisade Japanese Beetle Eradication Program recommends proper watering of lawns as a method of controlling this devastating pest. Watering lawns deep and infrequently will help dry out and kill eggs and the early stages of the larvae.

Soil moisture is extremely important in the life history of Japanese beetle. Eggs and the first stage of the white grub larvae are very susceptible and can be killed by drying of the turf. Female beetles will not lay eggs in dry soil and survival is very poor for small larvae in soils that dry out after egg-hatch has occurred.

Allowing soil to dry between irrigations can be a very effective method of helping to wipe out the Japanese beetle from the Palisade area. This dry-down technique, supplemented with the larval insecticide treatments planned for Palisade this month, will be a one-two punch that should eradicate the larval stages of the Japanese beetle. The insecticide will need to be watered in! TruGreen ChemLawn®, the firm applying the insecticide for the JB eradication project, recommends you apply three-quarters of an inch of water following insecticide application to activate the insecticide and move it into the root zone. Excessive watering can move the insecticide below the grubs and reduce the chemicals effectiveness. Cans or mugs set around the lawns can be used to determine when three-quarters of an inch of water has been applied.

To dry out eggs and larvae, homeowners should follow a schedule of infrequent (once a week), but deep watering (to the depth of a normal screw driver blade) for established turf. This would allow the soil to dry between waterings and still provide sufficient moisture to maintain the lawn. A deep watering of turf areas each week will provide sufficient water for nearby trees and shrubs that have roots in these areas.

Turf with a shallow root system may turn brown during this dry down period as it goes dormant due to reduced water. Dormant Kentucky bluegrass should recover as soon as water is applied later in the season. Homeowners who allow their lawns to go dormant for longer periods of time during this critical egg laying period will be much more successful in killing the eggs and larvae of Japanese beetle as well as other types of white grubs.

This dry down period should begin as soon as possible and extend through the month of September.

In addition to producing a lawn that is Japanese beetle free, deep and infrequent watering will help develop a deeper root system and a turf that is more drought tolerant and requires less water to maintain.

For more information on watering lawns, check out the web pages at http://WesternSlopeTurf.org or contact the Colorado State Cooperative Office in Grand Junction at 244-1834. For further information on the Palisade Japanese Beetle Eradication Project, contact Matt Camper, Project Coordinator, at 250-2694.