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

Problem Identifier Unit Screen//v.w/ RR Template Twig and Needle Blight

Problem
Needles, twigs, and branches turn brown. In some cases, the upper branches die from the tips back; in other cases, the lower two thirds of the plant dies. The needles often drop in late summer, starting at the tips and leaving the infected branches bare. Sometimes minute black dots appear on the dead needles and stems. This disease is most serious in wet weather or in shady locations. Plants may be killed.

Analysis
A number of different fungi cause twig and needle blight on plants in the cypress family. During wet weather, spores germinate on twigs and spread into the needles and twigs above and below the point of entrance, killing them. Reinfection may continue until the whole plant dies, or the plant may persist for many years in an unsightly condition. With some fungi, black spore-producing bodies develop and spend the winter on dead needles.

Solution
Prune out and destroy infected branches below the line between diseased and healthy tissue, making the cut into live tissue. Valuable specimens can be sprayed with a fungicide containing basic copper sulfate at weekly intervals throughout the growing season until new growth stops. Plant trees in areas with good air circulation and full sun.

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