UMass Extension Landscape Message June 3, 2011
"Winter Moth (WM) caterpillars have virtually finished feeding in MA at this time and have entered into the soil to begin pupation. No more damage will occur from this pest this year. Trees that were attacked by this pest should be considered to be stressed trees, especially if defoliated, and should be watered once a week during dry periods for the rest of the growing season. Fertilizer is not necessary nor is it recommended.
Lily Leaf Beetle eggs are maturing on the undersides of Asiatic lily foliage. These are tan at first but then turn orange and eventually a bright red just prior to hatching. Inspect now for the beetles and the presence of eggs. When occurring in small numbers, both eggs and adult beetles can be removed by hand and destroyed. If treatments are necessary a chemical pesticide, such as a pyrethroid, organo-phosphate, or carbamate, is usually required to obtain desired levels of control for the adult beetles. The larvae, which will appear soon, are easily treated with a product that contains Spinosad (e.g. Conserve SC)."