No. 9/August 12, 2019

White grubs
White grub is a common name for the larvae of June beetles, chafers and Japanese beetles that feed on the roots of turfgrass. The grubs can be found in the first 8 inches of soil beneath turfgrass. They are white, C-shaped larvae, about 1 inch long and have 6 jointed legs attached close to their small brown head capsule. Excessive root feeding by white grubs can leave turfgrass poorly anchored to the soil and can result in brown patches in a lawn that can be pulled back like a rug. This can impact the aesthetics of a lawn and, in some cases, can make sports fields less safe for children and athletes.

Nimblewill Noticeable During Hot Dry Conditions
There have been a few recent calls about nimblewill (Muhlenbergia schreberi).  With the hot, dry conditions we have had lately, our cool-season turfgrass growth has slowed, making warm-season nimblewill growth more noticeable.  While cool-season turfgrasses are dormant, nimblewill is actively growing and enjoying the lack of competition.  This unbalance can allow nimblewill to be a serious weed problem.

Fire Blight
I have received a few reports and questions regarding fire blight on ornamental pears. Fire blight is a bacterial disease that infects approximately 75 different species of plants, all in the Rosaceae family. Apples, pears, crabapples, and ornamental pears are the most seriously affected species. Other rosaceous hosts include cotoneaster, hawthorn, quince, firethorn, and mountain-ash.

Bacterial Leaf Scorch – New Molecular Service Available
It’s the time of the year that we start seeing bacterial leaf scorch symptoms develop in central Illinois, and several samples have been submitted that appear to be infected in the last few weeks. We are now offering a molecular test for this pathogen, which will reduce the turnaround time, and because it’s more sensitive than the previous ELISA test, ca be used any time during the growing season when symptoms appear.