This section has primarily to do with the categorization of trees into forest management unit groups; secondarily it deals with quality sort criteria.
For various economic and biological characteristics and position in the canopy the trees are classified into three groups; I - the best, II - support (useful) and III - unwanted (to be removed).
These tree classifications are necessary when carrying out cutting/harvesting in the logging site to increase overall bio-dynamics and provide the best conditions possible for quick regeneration and renewal of the forest massifs.
The tiers in the illustration refer the relative elevation level at which different groups of plants grow. That is trees of a tier are characterized by certain height, level of undergrowth and etc. It is important to clear the trees from all tiers, belonging to all three classes of trees.
The timber is mainly procured from tree class I, however at times of necessary sanitary maintenance we do indeed end up with timber material belonging to the second class of trees. But it is very important to understand that quality sort and tree classes are two very different things.
The quality sort of any timber product has to primarily do with physico-mechanical properties that are determined per type of product per size via special number of designed to test for these properties tests. We produce our timber products for Western European market using EN EUTR regulations regalement.
Once we determine the annual volume for various quality sorts, product needs, our technologists pinpoint the positioning of the needed trees in each geographic position and work out a tailored, to the location optimal, logistical and organization structure for the year’s harvesting.
Depending on the purpose of planting the trees, best features may be different. When forming the pine nut plantations, for example, the best trees are defined by having well-developed, low lowered crown regardless of the shape of the trunk; in the avalanche and landslide areas the trees and shrubs with a strong root system, low drooping canopy and thick branches (creeping cedar, birch, alder and others) would belong to the class I.
In natural forest massifs the healthiest trees are the ones full of woody twigs stripped of straight trunk, a narrow uniformly developed normally pine/leafy crown with no thick boughs, relatively fast growth, good rooting. They are selected from the trees I, II, III growth classifications too.
Auxiliary trees that are contributing to the purification of the best trees from the branches assist them in forming their crowns and trunks and help them with extra protection from sunburn and frost, as well as carrying out soil conservation and soil enrichment and a purification function. Auxiliary trees belong to all kind trees and plants species, with key characteristic beign that they have to reside in any part of the canopy, but mainly being subject to the canopy, or it could form the second tier of undergrowth. Most commonly used auxiliary trees are fir, spruce, birch.
Primarily these windfall trees, requiring sanitary and preventative work, so that these trees do not obstruct to the growth of the best and support trees. Such trees can be of different breeds (mostly aspen and birch), of all growth classes and they are can be in different parts of the plantations, but mostly in the upper canopy (tier). Some of the felled trees are also characterized by morphological defects of their trunks & abnormal development of the canopy. After harvesting our forest look like as depicted on the illustration below.
Continue reading at the from selection to harvesting section.