Very old and tall trees are most often damaged by electrical discharges, often towering over their surroundings. The size of the damage is very different and depends on such factors, how: discharge force, the species and size of the tree and the properties of the soil, such as the degree of humidity. To tree species, which most often attract discharges, include oaks, clones, pine trees, spruces, poplars d elms. Some species, like for example. book, birches and chestnut trees, they are damaged by lightning less frequently. This can be attributed to many different properties and characteristics of the tree, such as the content of various chemicals in its tissues and the overall conductivity associated with it, the quality of the root system, etc.. Trees with a deep root system are attacked more often than the plates with this system. It is also related to the quality of the geological substrate and its structure. Trees growing in areas with a high groundwater level are affected more often than those growing in dry areas.
The most common form of damage by an electric discharge is a bark stripe over a considerable length of the trunk, often with a thin layer of wood. During very strong discharges, the entire top of the trunk may shatter and the trunk will split over a considerable length. The high temperature accompanying the discharge may cause the tree to catch fire. The high humidity of the tree tissues usually prevents this from happening, dry trees light up easily, rotten interiors. An electric discharge can electrocute or kill living cells. Most often it concerns young roots.
In the event of slight damage to trees, treatments should be applied, which apply to open wounds, properly caring for them and protecting them against infection.
Difficult access to some places of damage causes, that are , they are generally neglected and consequently in trees such as e.g.. secondary infectious damage occurs very quickly. Therefore, in cases of very large and complicated damage, saving the tree may be abandoned. First of all, the required effort and resources should be analyzed and compared with the overall value of the tree. In assessing the tree should be taken into account: overall plastic value, age, overall health, species, ability to heal wounds and regenerate, safety of the surroundings. Decisions as to what to do, although they are sometimes difficult, they should be taken fairly quickly, because if a tree is left behind, all open wounds should be covered without delay.
The only way to protect trees against lightning damage is to use an appropriate lightning protection system. It consists of a lightning arrester placed at the top of a tree and a wire made of flexible metal cable, protected against corrosion by galvanization.. The line should be attached to the trunk with hooks protruding above the plane of the trunk on 20-30 cm. The end of the cable should be branched to 2-3 parts, led out in shallow grooves beyond the root reach zone and attached vertically to metal bars driven into the ground 1- 1,5 m.