No. 11/July 28, 2014
Mugs, Mothers, and Mums
The Plant Clinic was recently contacted by a gardener who had ordered and purchased mums but instead received something mum-like with huge rhizomes. Most likely what they received was mugwort.
Imported Longhorned Weevil
The imported longhorned weevil, Calomycterus setarius, has been numerous this summer. This pest is native to Japan and has been in this country since the 1920's. It is apparently controlled by natural enemies as noticeable populations occur infrequently. Adults feed on flowers, grass, shrubs, trees, and vines causing ragged edges on leaves and petals.
Potato leafhopper damage has become obvious during recent weeks, appearing to be heavier than in most years. These leafhoppers attack oak, maple, red mulberry, red bud, cottonwood, birch, apple, dogwood, hawthorn, wafer ash, euonymus, black locust, and cherry.
Adult Japanese beetles do not appear to be very numerous this year as predicted from the deeply frozen soils in the northern half of Illinois last winter, and the dry soils in non-irrigated turf during the second half of the last two summers. It is unlikely that insecticide applications to protect trees from defoliation will be needed in most areas of the state.
We have recently received reports of chinch bug damage in turf. Chinch bugs are typically not much of a turf problem in Illinois, being more of a pest problem in the Great Plains region.