No. 8/August 4, 2022
White Grubs
White grub is a common name for the larvae of June beetles, chafers and Japanese beetles. They are white, C-shaped larvae, about 1 inch long and have 6 jointed legs attached close to their small brown head capsule. The grubs can be found in the first 8 inches of soil beneath turfgrass where they feed on grass roots. 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.
Chicory
Chicory (Cichorium intybus) is an erect perennial growing from a large, fleshy, dark brown taproot. It has a rosette of basal leaves and tall, wiry stems that are sparsely leaved and branching. Chicory grows to about three to four feet tall. It is especially noticeable this time of year when in full bloom and can be found easily statewide along many Illinois roadsides.
Tar Spot of Maple
Tar spot of maple appears in this newsletter on a somewhat regular basis. Disease outbreaks have been more frequent in recent years, likely due to moist spring weather with above-average rainfall. Last week, I observed several trees with tar spots and received multiple questions about the disease.
Cercospora Leaf Spot of Hydrangea
Cercospora leaf spot of hydrangea is a fungal disease that affects bigleaf hydrangea, Hydrangea macrophylla; smooth hydrangea, H. arborescens; and oakleaf hydrangea, H. quercifolia. This disease does not kill the hydrangeas, but the spots can cause unsightly foliage. Severely infected plants may defoliate and often have reduced plant vigor and fewer flowers.