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Updates from the Help Desk Visit Woodford MG on August 7

For Immediate Release:

Please join University of Illinois Extension Woodford County Master Gardeners at the Eureka Public Library on August 7 th from 4:30 to 6 p.m. Whether you want to sit and talk about gardening or ask about a specific issue that you would like them to research, please visit the Woodford County Master Gardeners at their monthly help desk.

Many gardeners have been plagued with unwanted visitors, from the large populations of Japanese beetles to the sudden infestation of blister beetles in the tomato patch. In addition, caterpillars are eating the oak leaves and everybody is concerned about the large menacing wasps flying around the house known as cicada killers.

University of Illinois horticulture educator, Kelly Allsup, says helping gardeners find the silver bullet for Japanese beetle is a difficult task because controlling the larvae stage that lives in the ground for ten months of the year does not ensure the adults will not decimate your apple trees. Gardeners must have a plan as soon as they see the first beetle to prevent the large populations.

Allsup says " blister beetles have flown under the radar in my five year appointment as horticulture educator until this year." " They have come out in droves to eat on our veggies." Be careful when picking them off the plants as they will cause blisters with their spray. Other sources indicate they are only a temporary problem.

Oaks are being consumed by small caterpillars skelontonizing the leaves. The leaf looks white from the caterpillars eating the mesophyll layer of the leaf. Entomologists, Phil Nixon, says this is just an aesthetic issue and no control is warranted.

Cicada killers (Sphecius speciosus) are on the prowl, and there have been many inquiries about them at the Master Gardener plant clinics.

Cicada killers are solitary wasps with yellow banding on their abdomens. They appear in late July and early August and resemble large, black hornets. These insects are considered beneficial because they help control the annual cicada (Tibicen spp.) population. However, the excavating and burrowing that they do in open, dry ground when constructing their nests can be a nuisance for gardeners and homeowners.

Cicada killers are usually non-aggressive, although the male may investigate a person who invades its territory to determine that it is not another male cicada killer. Males are unable to sting. The females can sting but do so only when handled or disturbed because they lack the instinct to guard their nest as the honey bee does.

The singing of the annual cicadas causes the adult wasps to come above ground out of hibernation. On their search for annual cicadas, they will stop and drink nectar and water from gardens. Once the female cicada killer has found and paralyzed a cicada, she will carry it back to her underground nest. She places her prize in a nest cell, lays her eggs on it and seals up the cell. The larvae hatch in a few days and begin to feed upon the cicada before they form a cocoon to pupate for the winter and early spring.

For gardeners concerned about the safety of children or pets, U of I Extension suggests planting ground covers and grass to prevent bare spots, adding mulch, and using irrigation to deter nesting. An application of a carbamate-based chemical product to the nest will kill cicada killer adults and their larvae, but killing this beneficial insect is discouraged.

For more information on garden pests, visit the Woodford County Master Gardeners at the Eureka Library on August 7th.