What's New
What’s New
July 2026
What's Wrong with My Lilacs?
Fungal leaf spot of lilac has been favored by warm and wet summer weather conditions this year, which results in small brown spots, blight, and premature defoliation. Fungicide applications may help to prevent the disease by reducing new infections, but wouldn't eradicat them. So, good sanitary and cultural practices are critical to effectively manage the disease. For general information of fungal leaf spot diseases and strategies for their manament, please read the fact sheet Leaf Spot Diseases of Ornamental Trees and Shrubs.
New Fact Sheets Published Online
Link to Bacterial Leaf Spot of Herbaceous Ornamentals
Link to Foliar Nematodes of Herbaceous Ornamentals
May 2026
What's Going on My Cedar Trees?
The orange structure in the photo is cedar-apple rust fungus. Several species of Gymnosporangium can cause rust diseases on cedar trees. For more informaiton of Gymnosporangium rust diseases, please read the fact sheet Gymnosporangium Rusts: Common Cedar Rust Diseases.
April 2026
Two New Fact Sheets Published Online
Link to Cherry Leaf Spot fact sheet
Link to Rose Downy Mildew fact sheet
March 2026
What Happend to My Lawn
Gray snow mold is a common fungal disease in late winter especially after prolonged snow cover. Symptoms appear when snow melts, which including gray or bleached grass blades and reddish brown fungal structure on infected leaves. Linked please find a fact sheet Gray Snow Mold of Turfgrass in Home Lawns. For correct disease diagnoses, please send us samples by following the Sample Submission Guidelines.