No. 3/May 26, 2022

Modified Growing Degree Days
Insect development is temperature dependent. We can use degree days to help predict insect emergence and activity. Home, Yard, and Garden readers can use the links below with the degree day accumulations above to determine what insect pests could be active in their area.

Jumping Worm Update
The map of known locations of the invasive jumping worms in Illinois continues to expand as more reports are being submitted. In 2015, jumping worms were first found in Illinois with a total of seven reports in three counties. Currently, we have known populations in 42 counties with another five counties suspected of having jumping worms.

Getting to Know Common Wasps
Throughout the summer you may encounter many different types of wasps. These wasps can look similar at first glance but they often have very different natural histories and behaviors. While one wasp species might be aggressive and sting, another may be more interested in the food you’re serving at your family picnic or the juicy spiders in your garden. The following descriptions are intended to help landscape professionals and gardeners identify a few common wasps and determine whether they require control or may be neutral or beneficial in your shared space.

Weed Seedlings Recently Found in Central Illinois
Weeds can be challenging to identify. Tiny seedlings can be even trickier. Often times, letting your mystery seedlings grow a little so that all the parts are easier to see and handle can greatly help your identification efforts. Of course, waiting until your weeds are too tall can result in weeds that are more difficult to control or perhaps have exceeded label height restrictions. Therefore, timely identification is essential.

Cherry Leaf Spot
Cherry leaf spot symptoms are evident on edible and ornamental cherries in Illinois. This disease is caused by the fungus, Blumeriella jaapii. We usually see symptoms appear in early to mid-summer, beginning as small reddish/purple spots on the upper leaf surface. These spots turn brown and may merge together. The centers of the spots may drop out, giving the leaves a shot-hole appearance. The affected leaves often turn yellow and may prematurely fall from the tree.

Cultivar Reversion
Don't be alarmed, but you have mutants in your yard! What's more, they are hiding in plain sight! Many of the unique cultivars that we use in our landscapes originated from sports or mutations growing on plants with normal characteristics the species. Sports may differ by foliage shape, color, and branch structure. Breeders and growers propagate the more interesting sports, with some eventually working their way into the trade.