Spring burning has been recommended for seed fields, but may cause injury if growth has already begun. Downy Mildew Downy mildew. Pale leaves with grayish fungal growth on undersides. Downy mildew is common but seldom causes severe damage. It is favored by cool and wet or humid weather.
Leaves turn light green to yellow, and appear twisted and curled.
The tops of shoots often become dwarfed. A fine, grayish to violet fungal growth can be seen on the underside of affected leaflets. Downy mildew is most likely to be a problem in the spring. Varieties with resistance to downy mildew are available. Contact your district agriculturist for information on resistant varieties.