No. 12/July 16, 2010

White Grubs
Preventative treatment for white grubs is recommended to watered turf in those areas of the state where rainfall has been slight and non-irrigated turf is dry and dormant.

Sod Webworms
High numbers of sod webworm adults have been noticed around lights and in light traps. There are several species of sod webworms that are damaging to turf, but the adult moths look similar. They have light tan wings that are held tight against the body, giving the body a tube-like appearance.

Cicada Killer and Velvet Ant
Cicada killers are becoming numerous in turf areas. Adult cicada killers are large wasps, about 2 inches long and black, with yellow band-like marks. Velvet ants are parasites of cicada killer and bumblebee nests.

Peony Powdery Mildew
A recent peony sample at the University of Illinois Plant Clinic was covered with powdery mildew. The disease can be identified by its white, powdery growth covering the foliage.

Cherry Leaf Spot
A current problem on edible and ornamental cherries in Illinois is cherry leaf spot, caused by the fungus, Blumeriella jaapii. The pathogen is also known by one of its synonyms, Coccomyces hiemalis.

Foliar Nematode of Hosta
The foliar nematode is a pathogen in the genus Aphelenchoides. It lives in the plant foliage, not in the roots or soil.

Highway Invasives: Road Spread Weeds
Roadways and highways are becoming one of the major pathways by which invasive plants spread. Wind and air movement from passing vehicles help disperse seeds. Cutting and mowing, and regular road maintenance activities can aid in the spread of these invasives.

Brown Marmorated Stink Bug: Know This Invasive!
The Brown Marmorated Stink Bug (Halyomorpha halys) is native to Asia but has been transported to the United States and found in many states in the eastern U.S. Its presence in Illinois is unknown.