No. 7/June 4, 2010
NPDES General Permit Comment Period
The U.S. Environmental Protection Agency (EPA) has announced the public availability of a draft National Pollutant Discharge Elimination System (NPDES) permit for point source discharges from the application of pesticides to waters of the United States. This Pesticides General Permit (PGP) was developed in response to a decision by the Sixth Circuit Court of Appeals in which the court vacated EPA's 2006 rule that said NPDES permits were not required for applications of pesticides to U.S. waters.
Emerald Ash Borer Treatments
The recent discoveries of additional infestations of emerald ash borer in Illinois and surrounding states have increased concern among tree owners of the need to treat their ash trees with insecticide to protect them from this pest. Part of this concern arises from no known cases of survival of untreated ash trees when attacked by this insect.
European Elm Flea Weevil
European elm flea weevil, Orchestes alni, is feeding throughout the state. This is a tiny insect, about only 1/16 inch long. It is reddish, with black spots on the wing covers, and has on elongated snout with tiny mouthparts at the end. Adults overwinter, emerging in the spring to feed on leaves of Eurasian elms, including Siberian elm, where the damage is most noticeable.
Fire Blight of Ornamental Pear
This has been the week for symptom expression of fire blight on ornamental pear, at least in parts of Illinois. I have heard of multiple samples in Champaign, Sangamon, and Vermilion counties. We have received physical samples from Champaign and St. Clair counties. Symptoms seen now were initiated by infections from 5 to 30 days ago.
Cryptodiaporthe Canker of Pagoda Dogwood
Although resistant to most diseases, pagoda dogwood usually succumbs to Cryptodiaporthe canker when it reaches the ripe age of 20-25 years. Cryptodiaporthe canker is also known as the golden canker, due to the yellow-orange color of infected bark.
Rhododendrons Limited by More than Phytophthora Root Rot
If you have a rhododendron that is suffering but does not have Phytophthora root rot, consider the possibilities of Botryosphaeria canker or Armillaria root rot. Also consider noninfectious possibilities such as poor drainage, wet conditions, deep or shallow planting, and other abiotic factors. Diseases are not always the problem.
On the Watch for Gypsy Moth
One of the most notorious hitchhiking insects, the gypsy moth, is also one of the most destructive forest pests in the United States. This defoliator is a voracious eater; and when populations are high, they can devour all of the leaves from the trees and plants in a neighborhood.
Know Your Invasives: More Native Plant Resources
I received some great feedback from my article on "Learning to Identify Locally Invasive Plants," particularly on supplying some resources on alternative planting for gardens. Following that same theme, here are some resources that I've provided over time on our Illinois Cooperative Agricultural Pest Survey Program blog where you can find some of the latest news on invasives in Illinois.