Study on stem pests of elm tree in Uzbekistan

Abstract

Forest stem pests are of great interest as permanent components of forest biocenosis. In the forest they perform different roles; in a healthy forest they participate in the process of thinning and recycling the wood of naturally dying trees. In turn, they serve as food for other forest inhabitants. When the biological stability of plantings is violated, they act as pests and cause the death of still living trees. Many of them cause great physiological and technical harm. Stem pests constitute a large ecological group of insects that feed on the bark and wood of trunks and branches and have varied economic significance. Some colonize trees without visible signs of weakening, others are very weakened and even felled trees. Trees infested with stem pests die differently, this is due to the nature of the weakening of the tree and the infestation by pests. One of the main factors for the mass reproduction of stem pests is the physiological weakening of plantings, which provides food for pests. And the reasons that ensure the weakening of plantings are environmental factors: climatic (drought, excessive moisture, saline groundwater, windbreaks, snow banks, fires and others), and biotic (leaf-eating pests, tree diseases and human economic activity).