Preselection of the inventory

All areas designated as forest according to the NFI forest definition. The forest definition includes shrub forest. The target variable "forest area" is also used when classifying the total area as forest or non-forest.

Sum of the stem cross-sectional areas at a height of 1.3 m (level for measuring diameter at breast height [dbh]) of living trees and shrubs (standing and lying) with a dbh ≥12 cm.

Wood volume of the stem without bark and stump ≥7 cm in diameter (limit for merchantable wood) of all trees and shrubs with a diameter at breast height (dbh) ≥12 cm that were harvested between two inventories and were alive during the earlier inventory.

Stemwood volume of all trees and shrubs with a diameter at breast height (dbh) ≥12 cm with bark that were harvested between two inventories.

Stemwood volume of all trees and shrubs with a diameter at breast height (dbh) ≥12 cm with bark that were harvested, died or disappeared between two inventories.

Volume of stemwood with bark of all trees and shrubs ≥12 cm diameter at breast height (dbh) that were felled, died or disappeared between two inventories with the cause of death given.

Wood volume of branches ≥7cm in diameter with bark (limit for merchantable wood of all trees and shrubs with a diameter at breast height (dbh) ≥12 cm that were harvested between two inventories and were alive during the earlier inventory.

Wood volume of the stem without bark and stump and the branches with bark ≥7 cm in diameter (limit for merchantable wood) of all trees and shrubs with a diameter at breast height (dbh) ≥12 cm that were harvested between two inventories and were alive during the earlier inventory. The target variable "merchantable timber harvested" is an approximation of the amount of usable wood. It comes closest to the volume of timber harvested recorded in the Swiss Forest Statistics.

Volume of stemwood with bark of all trees and shrubs ≥12 cm diameter at breast height (dbh) that were removed from the forest because of damage that occurred between two inventories rather than due to silvicultural planning. The characteristic is derived at the sample plot level from the fellings of the tally trees and the proportion of sanitary/salvage fellings (according to information from the foresters).

Stemwood volume of all trees and shrubs with a diameter at breast height (dbh) ≥12 cm with bark that were not removed from the forest as part of silvicultural planning, but because they had been damaged by insects between two inventories. The variable is derived at the sample plot level from the harvested tally trees and the proportion of sanitary/salvage fellings (according to information provided by the foresters).

Stemwood volume of all trees and shrubs with a diameter at breast height (dbh) ≥12 cm with bark that were not removed from the forest as part of silvicultural planning, but because they had been damaged by wind between two inventories. The variable is derived at the sample plot level from the harvested tally trees and the proportion of sanitary/salvage fellings (according to information provided by the foresters).

Increase in the stemwood volume between two inventories of all surviving trees and shrubs with a diameter at breast height (dbh) ≥12 cm with bark, the stemwood volume of all ingrowing trees and shrubs with bark, and the modelled increase in the stemwood volume of the losses with bark during half the inventory period minus the volume of mortality. The net increment thus corresponds to the increment (=gross increment) minus the volume of mortality.

Stemwood volume of all trees and shrubs with a diameter at breast height (dbh) ≥12 cm with bark that were harvested, died or disappeared between two inventories.

Volume of stemwood with bark of all trees and shrubs ≥12 cm diameter at breast height (dbh) that were felled, died or disappeared between two inventories with the cause of death given.

Stemwood volume of all trees and shrubs with a diameter at breast height (dbh) ≥12 cm with bark that died naturally between two inventories (e.g. due to windthrow or insects) or disappeared (e.g. due to avalanches), but that were not harvested. Mortality is the sum of natural losses and the remaining mortality.

Number of stems of living trees and shrubs (standing and lying) with a diameter at breast height (dbh) ≥12 cm.

Measure of the density of a stocking calculated from the number of stems per hectare (in NFI trees and shrubs with a diameter at breast height [dbh] ≥12 cm) and the mean diameter. With a callipering threshold of 0 cm, the SDI is largely independent of the site quality, tree species composition and stand age.

Number of stems of all living and dead trees and shrubs (standing and lying) with a diameter at breast height (dbh) ≥12 cm. The total number of stems is the sum of the number of stems and the number of deadwood stems.

Number of living and dead trees and shrubs (standing and lying) ≥12 cm diameter at breast heigth (dbh) with damage. Only the two most important forms of damage to a tree are recorded. Since a tree may be damaged in different ways, it may contribute more than once to the total number of stems with the two most important forms of damage.

Stemwood volume of living trees and shrubs (standing and lying) with a diameter at breast height (dbh) ≥12 cm with bark.

Stemwood volume of all living and dead trees and shrubs (standing and lying) with a diameter at breast height (dbh) ≥12 cm with bark. The total wood volume is the sum of the growing stock and deadwood volumes.

Volume of stemwood of all dead trees and shrubs (standing and lying) with a diameter at breast height (dbh) ≥12 cm with bark.