The extent and nature of damage to trees by low temperatures are associated with the biological characteristics of species and varieties, rootstocks, the age and condition of plants, garden location, as well as the terms of his care. Prosperous wintering garden depends on preparing for it, the weather conditions of the previous season, the moisture from the provision of plant and harvest their overload. The prolonged vegetation also affects the hardiness of trees. One of the signs of readiness for the winter garden - the timely completion of the autumn leaf fall. It shows a sufficient accumulation of carbohydrates and aging tissues. The incompleteness of this process - the main cause of reduced resistance to winter desiccation and frost.
The resistance of trees to low temperatures are also reduced when applying a large number of major injuries after cutting in the first half of the winter. Therefore, even in the south in the winter pruning begin with the most winter-hardy varieties - summer and autumn.
Particularly affected by frost in the forks of the young branches with sharp angles of divergence. It is these forks and should be avoided during the formation of the crown. The angles of divergence of 50-60 degrees increase frost and leafy - even fouling branches in length. More vulnerable open branches bare spots.
It should be borne in mind that in the period of forced rest heartwood least resistant to freezing, the most stable - the cambium (Cloth in the stems and roots of providing their growth in thickness), bark and wood occupy an intermediate position. If you hit the cambium - the tree dies; preserved - under favorable conditions the plant may recover.
Therefore do not rush to remove branches and trees: after heavy frost is difficult to determine the state of the cambium, this takes time. However, we must remember that in the growing cambium not tolerate cold temperatures. The consequences of freezing of the spring and fall - the most severe.
The ability to recover podmerzshie trees, especially after the harsh winters with little snow, and is directly related to the state of the root system. When soil freezing to minus eight degrees can damage the roots of vegetative rootstocks of apple, pear, cherry. If you have suffered thin fibrous roots and remained intact conduction system and the cambium, the trees are restored.
The extent and nature of damage to fruit trees determined in several stages: 10-12 days after the critical frost after bud break and early summer, when the crown overgrown foliage.
Externally freezing of much to change the color of the bark, and wood core. It becomes more expressive after thawing. So, the color of apple wood and bark can be of vitreous light green (with an initial extent of damage) to brown, brown, dark brown (with a strong frost build-up). In pears, peaches and other stone fruit darkening can be even more intense - to black.
By darkening fabrics in cross sections on trunks from different angles, in the forks of branches and branches along the border and identify pockets of damage bark and cambium wood.
With significant damage there is a smell of alcoholic fermentation, the bark is peeled longitudinal stripes. However, even a sharp change in color of fabric is not always a sign of death.
Yet the most common damage to trees is the partial or total loss of generative buds.
To establish the state of the kidneys to the method of germination branches. On a typical trees of different varieties of stone taken away from the kidneys to one hundred, with apple and pear - at thirty. In cross sections show a darkening of the kidney tissue. Take into account the number of dead and surviving buds and flowers of pome melkokostochkovyh rocks. Do peach and apricot buds counted the dead (they have one at the rudiment of a flower in the kidney). We melkokostochkovyh species (cherries, sweet cherries) podmerzshie kidneys sometimes do not fall, the trees are blooming, but do not form fruit: at the flowers are damaged pistils.
The dead flower buds of peach, apricot and plum trees turn brown and not revealing, crumble in the early growing season. In seed species rarely kidney frosted over, their freezing after discovering other organs.
It is worth noting that the generative buds are damaged more in the lower part of the crown at the top, they are saved.
