Problem Identifier Unit Screen//v.w/ RR Template

Problem Identifier Unit Screen//v.w/ RR Template Leafminers and Tip Moths

Problem
Leaf tips turn yellow, then brown and dry, contrasting sharply with the healthy green foliage. Damage is most severe in plants growing in shady areas. When a yellow leaf is torn open, a small (1/5 inch long), greenish caterpillar with a dark head may be found inside. Gray or brownish moths with a 1/3-inch wingspread may be seen flying around the plant in April, May, or June.

Analysis
(Argyresthia species)

Several species of insects, known as leafminers in the eastern United States and tip moths on the West Coast, infest arborvitae, cypress, and juniper. Damage is unsightly, but plants may lose over half of their foliage and still survive. The larvae spend the winter inside the leaf tips. When the weather warms in late spring, adult moths emerge and lay eggs on the leaves. The eggs hatch and the larvae tunnel into the leaf tips, devouring the green tissue. The tips above the point of entry yellow and die. The larvae feed until late fall, or through the winter until early spring.

Solution
Spray with an insecticide containing acephate or diazinon when eggs are hatching in June or July (mid-August in the far northeastern states). Trim and destroy infested leaves in fall and spring.

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