This and that         

By John Fulton

[JULY 3, 2006]  Insects seem to have been the major story of the past several weeks. Well, the saga continues. Japanese beetles continue to be the most impressive of the insects so far, at least for those who have them. There are still soldier beetles around, and mosquito populations are exploding.

Let's delve a little further into Japanese beetle feeding patterns. As many now know, the beetles give off a pheromone when feeding that attracts other beetles to feed in the same area of a plant. That's why it is said that they feed in hoards.

Another factor is what the plant is. Usually, red maple, silver maple, boxwood, shagbark hickory, flowering dogwood, persimmon, euonymus, white and green ash, holly, butternut, tulip tree, sweet gum, magnolia, white poplar, common pear, white oak, scarlet oak, red oak, and common lilac are relatively free of feeding. Box elder, black oak and American elder usually have light feeding. Japanese maple, Norway maple, horse chestnut, hollyhock, gray birch, American chestnut, rose of Sharon, shrub Althea, black walnut, flowering crab apple, apple, London plane, Lombardy poplar, cherry, black cherry, plum, peach, apricot, roses, sassafras, mountain ash, linden, elm and grape are nearly always severely attacked by the adult beetles.

Also remember there is a grub stage to the Japanese beetle. The adult beetles will be with us for a month or so; then they lay eggs. These eggs will hatch out into a grub in early August. Large numbers of beetles probably means a large number of grubs, with favorable weather conditions. Treatments are the traditional grub treatments, applied in August or early September, or one of the alternative type applications.

The alternative applications include "Milky Spore" dust, which is actually a bacteria, or parasitic nematodes. The Milky Spore is a bacteria that affects only Japanese beetle larvae (doesn't affect other grubs) and takes a few years of fairly high numbers of Japanese beetle grubs to distribute it well. The nematode can occasionally be found in specialty catalogs.

Mosquito control

Mosquito numbers are rapidly increasing. With the threat of West Nile virus in the area, as there has been positive identification in some surrounding counties, control becomes more of a concern. Of course, eliminate sources of stagnant water by draining or changing water in birdbaths, wading pools and tires. One chemical control option is the Bt israelensis in water. This is great for ditches, small ponds and other places where water is present all the time. Area sprays of malathion, permethrin or tetramethrin will do quite well.

Cut tall grass and treat shrubs and vines, as these are resting places for the mosquito. You can also avoid times when mosquitoes are more prevalent, such as early morning and at dusk. Use of an effective repellent like DEET is your best preventive when you are in areas with many mosquitoes. The repellent will also be helpful in preventing ticks and chiggers. With the proper precautions, you can still enjoy the outdoors this summer.

[John Fulton, unit leader, University of Illinois Extension, Logan County Unit]