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Why pines die in the Moscow region

By the nature of my activity, I often have to drive along our main highways in the Moscow region. At the beginning of autumn, he drew attention to the mass death of old and middle-aged pines. This was especially striking on the forest edges and on the clearings of spruce trees that were killed by the typographer's bark beetle. The symptoms of the dead trees were similar: still green crown and bark peeled off by woodpeckers from the beginning of the crown and up to the level of 1-1.5 meters from the ground.

Pine tree that died after settling with blue pine goldfish. The bark is peeled off by woodpeckers. The passages of the larvae developed under the bark are visible.Flight holes of the blue pine gem.

I got interested and drove up to see what was the reason for the death of the pines. Oval flight holes of beetles and winding passages of larvae on the inner side of the torn bark are clearly visible on the bark. In the shape of the flight hole, the pest is a goldfish. These are very beautiful, shiny beetles that belong to a large group of stem pests. The larvae of many species of goldfish develop under the bark of trees and bushes, gnawing long winding passages in the bast. In the place of development of the larva, the conductive tissues of the plant die and the vertical transfer of organic matter along the canteen is disrupted. The fact that the crown of pines is still green is understandable - the vessels of the wood, which are not damaged by the larvae, are responsible for supplying the crown with water. The dying off of branches and needles will occur later - closer to spring. By the size of the flight hole, he suggested that the pest is a blue pine goldfish (Melanophila cyanea F.).

I examined the bark knocked down by woodpeckers, tore off the bark closer to the butt - I found larvae in the bark and the goldfish that died during the flight. The assumptions were confirmed - the death of the tree was caused by the development of the blue pine goldfish. The settlement of trees took place in the summer, since there are practically no bark beetle passages, and the larvae of longhorn beetles were found only in the butt area. Apparently, a number of dry years and snowless winters, as well as a sharp change in growing conditions due to the cutting down of dead spruce forests in the area, led to a sufficiently strong weakening of the pines, as a result of which they were inhabited by golden beads and died.

Blue pine goldfish and its larva from a dead pine tree

Forecasts for summer 2015 are disappointing:

  • Another snowless winter led to an even greater drop in the water level in the soil horizons.
  • It is more difficult to deal with golden beetles than with bark beetles because of the extended flight of beetles for almost the entire summer (from June to almost the end of August).
  • No one is engaged in the prevention of control and tracking the colonization of pine forests by this type of pest.
  • The number of the pest will grow, the pine forests will be settled further and, first of all, well-lit and warmed up pines growing in the forest edge zone and on clearings of spruce forests killed by bark beetles are in the risk zone.
Blue pine goldfish and its larva from a dead pine tree

Photo by the author

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