No. 6/May 28, 2010
Gypsy moth caterpillars hatch when common lilac, Syringa vulgaris, blooms. However, its main hosts, oaks, are typically just leafing out at that time. It is recommended to delay treatment until there is sufficient foliage expansion for sprays to have enough leaf surface to be effective.
Boxwood psyllid, Psylla buxi, can be found feeding on boxwood in many portions of Illinois. Boxwood psyllids are small (1/16-inch), grayish green insects that are normally covered with a white, waxy, filamentous secretion that partially covers the body, providing protection from parasitoids and sprays of pest-control materials. Winged adults appear in late May and June.
Hawthorn mealybug is being found in high numbers on cotoneaster in northeastern Illinois. Hawthorn mealybug, Phenacoccus dearnessi, is also known as two-circuli mealybug. It feeds on hawthorn, cotoneaster, pyracantha, mountain ash, amelanchier, and other rose family plants.
Helpful Info from NPDN
The National Plant Diagnostic Network (NPDN) is indeed a network of people employed at land grant universities, federal agencies (such as APHIS), and state departments of agriculture, consultants, and other stakeholders.
Know Your Invasives: Garlic Mustard
One of the seemingly fastest moving invasive plants in Illinois is garlic mustard. In fact, in one Illinois study, it advanced an average of 20 feet per year, expanding as much as 120 feet per year. It aggressively invades forested areas and can be found along roadsides as well. It likes shaded areas, especially disturbed sites and open woodland.
On the Watch for Emerald Ash Borer
This metallic green beetle was recently found in Iroquois county, just north of Loda. Citizens are asked to be on the lookout for this invasive pest, but do you know what you are looking for?
Raspberry Orange Rust
Customers growing raspberries other than red raspberry may be seeing an orange growth on the leaves now. This is a fungal disease called orange rust that infects blackberry, black raspberry and purple raspberry. Red raspberry is resistant. Raspberry orange rust should not be confused with the late leaf rust disease of red raspberries.
This spring, many plants have become infected with anthracnose. There are several similar fungi that cause anthracnose diseases. Most of these fungi infect foliage and overwinter on the dead leaves.