18-09-2018
Why the pine forests are drying?
Recently, in the forests of Ukraine there was a emergency situation, caused by the confusion of pine tree in large areas. The reason for this is the upper crust (Ips acuminatus Gull), which belongs to the family of the rigid bats or beetles. The large number of pests is able to settle and healthy pine trees. First, the beetle is inhabited by thin branches, and later passes to the top of the trunk, in the area of the fine crust, where mainly the life cycle passes. The initial sign of settling of pine tree trees is the so-called "Gilkopin", when a large number of broken twigs are placed under a crown of trees. The drilling of the needles on the top shoots and the upper part of the Crown testifies already to the death of the tree. The period from the beginning of settlement to total death of the tree lasts 2 – 3 months. But the coronoid for such a short term is not able to completely destroy the tree. In its passages are developing pathogenic fungi, which cause a complete blockage of the SAP vessels and the gray wood.
But how happened that a beetle of size 2 – 4 mm managed to settle pine forests on a large area? The reason lies in changing climate conditions. Due to increase of air temperature and intensity of precipitation there is a weakening of pine tree-Mills. The most prone to weakening and settling of the crown are artificially created clean pine plantations, which consist of most of the area of the Forestry fund of Ukraine. Mixed pine plantations of scabies reluctantly, but also settling, preferably by the side of the hills and the log cabins, with a well-lit side.
What is the reason for such selective settling of pine trees in clean and mixed plantings? First of all, it is necessary to pay attention to physiological features of protection against stem pests that have in the arsenal of pine trees. A healthy, non-weakened tree is capable of counteract the pests by means of a feeder. When there is settling of this or that stem pest, a healthy tree produces a greater amount of feeder and fills the insect in place of its settlement. In other words, a healthy tree creates a crossing on the road to the settlement of pests. Instead, a weakened tree cannot resist it.
Vitality and resistance of pine trees directly depends on the presence of nutrients in the soil. In pure pine planting the litter is poorly decomposed, forming a sour coarse humus, increases the acidity, slightly worsens the structure and decreases the soil aeration. Unlike pure pine trees, mixed plump bedding helps to better access oxygen to the roots of trees. The presence of bedding of the hardwood leaf contributes to its best decomposition, enriches the soil with nutrients, reduces the intensity of the grass cover, increases the stability of the plantings. The opadhardwoods are nitric, potassium and phosphoric compounds that are required to be woody, improving the properties of the soil. That is, the participation of deciduous breeds in pine plantations contributes to the improvement of vitality and sustainability of pine trees.
In past times, the LITSIVNYKY was used during the creation of forest crops of pine a large range of concomitant deciduous wood and shrub breeds to improve the growth of the main breed. But now, unfortunately, this assortment of breeds is almost not used in forest-cultural production. And so it was formed that the creation of the vast majority of monoccultures of pines together with climate changes and caused the drying of pine trees.
Unfortunately, the fight with the top loaf using chemical methods does not give proper results. By spending their life cycle under the bark, the bark is almost achievable for the action of insecticide. So far the only way to deal with the tip of the upper crust is selective and solid sanitary chopping in the cells and perimeter of the swelling. But while the drying of pine tree Mills failed to stop. Hot weather this summer only contributes to the formation of new cells of the pine tree.
But despite all the problems, scientists do not retreat. Laboratory for protection of Forests of Ukrainian Research Institute of Forestry and Agroforest reclamation them. G. M. Vysotska in cooperation with the "Kharkivforest protection" group began to grow natural enemies of the tip-loaf, ant (Thanasimus formicarius). Already in July of this year in the forests of the Sumy Regional Department of Forestry and Hunting economy (SE «Okhtyrka forestry» and SE «Krolevetsky forestry») The party larvae of Ant was released in the cells of pine tree.
Also, in the future to prevent the emergence of pine trees from the action of pests, it is necessary along with the use of lysine and biological methods of protection to cultivate persistent mixed pine plantations.
And. At. Bobrov, K. S., N. S. Se "Novgorod-Siverska Lvat"
Recall earlier reported that the area of the drying of trees is almost 400 thousand hectares