Fractures of trees at forks
The causes and effects of fractures. This type of damage causes the most serious damage to trees. The fracture is in most cases the result of a mechanical weakening of the bifurcation site. In such places, two or more branches or limbs adjacent to each other are pressed against each other. These pressures are caused by the increase in thickness and occur the earlier, the smaller the bifurcation angle (drawing).
Drawing. Successive stages of damage in a narrow bifurcation of the limbs.
If the bifurcation angle is large, the limbs are not pressed against each other. Maintaining this condition is the primary goal of creating the crown structure. Pressures too close to adjacent branches can be so great, that they cause stress, followed by cracks and splits in the trunk. Such a crack occurs most often during strong winds, when one of the branches is tilted back. When the wind force is strong, a complete breakage may occur at the point of fracture. Wood in the persistent cracks of the forks is very easily infected due to rainwater accumulating in these places.. Various contaminants also get into such gaps, which are conducive to maintaining high humidity and progressing infection. The healing tissue formed at the edges of the fracture plane is crushed and rubbed as a result of the movements of the split branches. It is accompanied by leakage of juices (assimilation products), being an excellent breeding ground for various bacteria and fungi. In such conditions, the decomposition of the wood is very fast and progresses downward in the trunk and spreads further and further to the branches.
Very often, the infection of the wood in the fork occurs before it breaks, weakening the place where the branches join; the crack then becomes a secondary damage. This is why, that many of the narrow forks create pocket-like gaps, mis itp., in which water trapping and accumulating organic materials favor the degradation of the bark, and then wood. Such damage, based on the progressive decay of the trunk wood, is very common in limes and maples as a result of defective crown bifurcation. In some cases, filters made of plastic tubes can be inserted into the resulting depressions at the bifurcations, drainage of accumulating water.
Damage to the natural bond, what healthy wood is, always leads to branch breakage, that is, to the loss of a significant part of the tree. The resulting large wounds disfigure the tree, it is very difficult to heal them completely, and even nurturing, preventing the infection of the wood – is not easy. Treatment consists in leveling the entire plane of the fracture with a chisel, including the shore, giving it a vertically elongated shape and securing it by the means already discussed.
In the event of a large internal decay of the trunk wood, breaking off a large limb, and often a large part of the crown is tantamount to the destruction of the entire tree. Undertaking nursing procedures in most of such cases is not justified. Such trees are often a threat to people and should be removed.
Damage caused by a too small bifurcation angle can be avoided by appropriately shaping the crown, and most importantly by maintaining higher branching angles. Preventing bifurcations from breaking, both healthy, as well as those with damaged wood, it is possible by installing special bindings.
Bindings to prevent breakage.
Such bonds involve joining two or more branches together in order to hold each other together, to prevent cracking or breaking at the bifurcation. These bonds can also very effectively prevent breakage of branches and limbs above the branch point (bifurcation). The purpose of binding is not only to protect the tree from damage, but very often it is necessary for security reasons. Such protection is of great importance on roads for car traffic, next to the electric wires, telecommunications and other devices, for which trees can pose a risk.
