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Potato Leafhopper Damage Revisited and Cricket and Nuisance Pest Control
By John Fulton
 

[September 09, 2014]  Potato Leafhopper Damage Revisited - The effects of the potato leafhopper on ornamental shade trees are very striking at this time – particularly on red maples. The red maples are among the most severely injured trees by the leafhopper. Other trees affected include oaks, other maples, red mulberry, red bud, cottonwood, birch, apple, dogwood, hawthorn, euonymus, black locust, and cherry. Infection most likely began in May and June, and the effects are now visible.

The leafhopper is a small wedge-shaped insect, which is light green. Their length is about an eighth of an inch, and they are attracted to light at night. At times of very large numbers, they look like a fog around outdoor lights. Young leafhoppers look like the adults, but they can’t fly. They suck plant sap, then inject a toxin back into the plant leaf. They feed at “points” on leaves, meaning the tips or the lobes. That is where you find the damage beginning.

Damage appears as curled, stunted, mottling, and in the case of red maples in particular, the red coloration is the standout part of the damage. Other discoloration can also appear with lighter leaf areas or brown or black areas. There is often a “v” shaped area at the point of feeding with it progressing from yellow, brown, then black, then tattered out by wind and rain.
 

Treatment is probably only justified on young and nursery stock, and at this time of year, the damage has mostly been done. It would have taken preventative insecticide sprays much earlier in the season to prevent the damage we are now seeing.

Cricket and Nuisance Pest Control

Nothing says approaching fall like the chirping of crickets in the middle of the night. Unfortunately, they are probably coming from inside the house. The best offense is a good defense in this case. If you have been following a foundation spray program all year, keep it up. If you haven’t been, it is probably time to start. It cuts down on crickets, millipedes, spiders, ants, and many others that find their way inside. Of course, fall is a prime time for nuisance pests entering the home.

 To accomplish a foundation spray, you would select a material such as permethrin or bifenthrin to begin with. Then spray the foundation and the adjacent foot or two of soil or plant material with the spray mixture. Both these products are cleared on most types of plants. Foundation treatments should be applied every 7-15 days depending on the temperatures. The materials break down quicker in hot weather.

Foundation treatments won’t prevent everything from getting in the house, and they certainly won’t kill things already in the house. For insects already in the house, you have a few options. The first is mechanical control. This is fancy language for something like a flyswatter, shoe, vacuum cleaner, flypaper, or glue boards. The next is chemical control. This basically means aerosol cans inside the house. The most common ones are for flying insects or ants, although many of the flying insect killers now have permethrin in them and can last quite a while.

[By JOHN FULTON, COUNTY EXTENSION DIRECTOR SERVING LOGAN, MENARD, AND SANGAMON COUNTIES]