Forest Restoration Methods
Burning is a forest restoration method. The sites picked for burning are usually of low or medium fertility, because highly fertile forests are usually too moist to be burned. When the forest is burned, a part of the trees are charred. Some die immediately, and some die over a period of years. As a result, wood in all stages of decay is continually produced in the area. The diversity of tree species usually increases after a fire. The new tree stands sometimes form in clusters, sometimes separately, with varying distances between the trees. The trees are of different ages, because part of the original stand survives the fire. Increased insolation caused by burning is a prerequisite for certain rare or threatened species.
Restoration fires are carefully planned. Part of the trees in the area are felled in order to facilitate the burning, and increase the amount of charred wood formed. A protective zone is usually cleared around the restoration site by removing foliage and exposing the mineral soil. The ground has to be dry enough at the time of burning. Forest burning requires numerous people for fire extinguishing and guard duty.
Small openings are usually created in young, very monotonous conifer forests. The openings are created by felling all conifers within an area of a few hundred square meters. There are two main methods. Small openings, in which new deciduous trees may grow, can be created. Alternatively, conifers can be felled around the existing deciduous trees which are loosing the competition for light and living space. The creation of small openings increases the amount of deciduous trees, and increases the mosaic-like structure of the forest. The saplings growing in the openings also increase the diversity of the age distribution of the stand.
Increasing the Amount of Dead and Decaying Wood
The amount of dead and decaying wood is increased primarily in areas where the natural continuum of decaying wood is in danger of being severed, and in areas lacking decaying wood but with valuable species in the vicinity.
Dead and decaying wood can be produced by stripping the bark off trees while they are standing, or by cutting them down. Both stripping and felling are mainly done by chainsaw. Barking or marking irons can also be used for stripping. Excavators can be used to fell trees together with their root clumps. The mineral soil thus exposed forms a good substratum for saplings.