Early effects of drought include wilting or discoloration of foliage, shedding of leaves or needles, and reduction in growth. As drought stress continues, plants become more susceptible to disease and insect issues to which they would normally be resistant. Pests like borer beetles and canker fungi are often only found attacking stressed trees.
Avoiding drought stress for woody plants requires multiple tactics. Irrigating plants is essential in these conditions. Mulching the root zone with fresh wood chips will help to retain irrigation or natural moisture in the soil, and it will help to regulate extreme soil temperatures. Application of potassium phosphite is also beneficial. Research has shown that this treatment increases plant tolerance to environmental stresses such as drought, and also improves resistance against some secondary stress-related disease issues.