No. 6/July 1, 2020

Japanese Beetles on Ornamental Plants
They’re back! Adult Japanese beetles (Popillia japonica) have emerged in Illinois and are beginning to feed on ornamental plants. Japanese beetle adults have a broad host range, feeding on over 100 plants including linden, buckeye, rose, crabapple, apple, grape and raspberry. They may feed on the foliage, flowers and fruits of their host plants, skeletonizing leaves so only the leaf veins remain. Beetles tend to feed on and damage the upper portions of plants which can lead to heavy damage in the tops of trees. In some cases, this means that the damage can go unnoticed by passers-by and may not require treatment. While the damage can be unsightly, it does not usually result in dieback or the death of the plant.

Yellow Nutsedge Identification and Control
Overall, sedges are pretty good at disguising themselves as they superficially resemble grass. They blend into a lawn decently with growth that is similar to that of turf. It is the yellow-green color however, that makes yellow nutsedge noticeable. It can be found easily this time of year, unless of course it is hiding within other plants in a landscape bed. Of course, the most successful weeds learn to perfect this art. Job well done, nutsedge growing within my rose bush.

University of Illinois Plant Clinic Summary of ornamental, fruit, and vegetable samples received June 2020
It’s no surprise that our sample numbers are lower than usual this year. While the Plant Clinic remains open, we are currently operating with staff in the lab only as needed for diagnostics. We are often not able to answer or return phone calls in a timely manner. If you need to contact us, we suggest emailing for the fastest response.

Elderberry Rust
The common elderberry, Sambucus canadensis, is an adaptable, native shrub known for its showy white flowers and edible fruit. It has a rather unkempt growth habit, which often limits its landscape use to naturalized areas. The common elderberry also happens to be one of the more common plants that I am asked to identify. The most recent request included photos with symptoms of elderberry rust, a disease that I had not seen before.

Safely Storing Pesticides During the Summer Months
Proper storage of pesticides is essential for protecting not just the chemical but also people and animals. Some items to consider are the pesticide’s container, environmental conditions, and location of the pesticide storage area. These conditions can have an impact on the pesticide’s shelf life.