STEADINESS OF POPLAR TO PRUNING IN THE CONDITIONS OF THE CITY OF ARKHANGELSK
The aim of the study was to assess the state of the pop-lar, depending on the method of cutting the crown and its biological characteristics. The studies were conducted on the main avenues and streets of the city of Arkhangelsk in the plantations with a greater proportion of poplars by the method of individual counting of tree species. For poplars the catego-ry of state, pathology, the height of cutting the crown, height and diameter of tree trunks were taken into account. Pruning crown poplar trees were classified from slightly to severely damaged. The condition of poplars after pruning crown was due to the height of cutting trunk, the diameter of the trunk, the age of the tree, the method of pruning. The first pruning of poplar should be performed at young age. Poplar trees with a trunk diameter of more than 30 cm, previously untreated crowns then pruning crown by the "pillar" perish in the way "on a column". At subsequent pruning the crown of the tree pruning height of the trunk is recommended to be not less than 5-6 m. Under homogeneous conditions at different prun-ing crown height between the trunk cutting height and the category of tree state, an inverse significant reliable tightness of the connection was found (r = - 0.62 at t = 8.4). The indica-tor of low level of pruning trees vitality is the presence on the trunks of wood-destroying fungi fruit bodies. When poplar trees are made pruning crown by the "pillar" method the probability of their destruction by wood-destroying fungi in-creases. Between the diameter of the tree trunk and the oc-currence of fruit bodies of wood-destroying fungi high reliable tightness of the connections was noted (r = 0.75 is noted at t = 6.3). Fruit bodies of wood-destroying fungi begin to occur in ripening pruning crown trees. The most resistant to wood-destroying fungi after pruning crown was the laurel poplar; the least resistant was fragrant poplar.