Spruce Pine Stands Research Articles

Влияние структуры древостоя на плотность древесины сосны и ели в черничном типе леса

Mixed stands of spruce and pine of myrtillus y forest types occupy large areas of the forest
 fund of the Leningrad region. For the theory and practice of forestry it is important to know the impact
 of plantations on the density of wood in bunk mixed spruce-pine stands. In mixed stands of
 pine and spruce disks and cores of wood species were selected from the model tree to determine the
 basic density by the method of maximum water capacity. The study of basic wood density of pine
 and spruce in the coniferous bunk stands revealed that its rates are higher for both species in the
 mixed forest stand than in pure coniferous plantations in the region of the study. With the predominance
 of pines in the stand composition, its wood density is higher than in stands dominated by
 spruce. Density of pinewood increases from smaller to larger classes of stand diameters. Variability
 of wood density by diameter of trunk is higher in spruce than in pine in mixed stands. In stands, after
 cutting dilutes the density of pinewood is lower than in the plantation, which is not passed with
 felling. In the bunk spruce-pine the stand, to the age of maturity, larger mass of stem wood of coniferous
 species is formed than in the pure one-tier stands of pine or spruce. Developed regression
 equations depending on the density of the wood at a height of 1.3 m to the average density of trunk
 allow for a more accurate assessment of this parameter in mixed stands than previously published
 equations for pure stands of myrtillus forest types for the study area.

Tree Cavity Resources in Spruce-Pine Managed and Protected Stands of the Białowieża Forest, Poland

Tree cavities are vital resources for many animals, especially birds and mammals. We aimed to determine density of cavity resources in coniferous spruce-pine (Pinus/Picea genera) stands of the Białowieża Forest, Poland, and to correlate their presence with tree species composition, and characteristics of trees and stands (condition, DBH, basal area). We conducted studies in spruce-pine stands with no (national park), medium (seminatural reserves), and high (managed forest) management activity. We measured all trees within 50-m × 50-m sample plots (eight plots in each zone) and searched for all tree cavities. The highest density of cavities was observed in the national park (12.5/ha) and the lowest in managed plots (3.0/ha). Most cavities were found in dead trees (74.4%), mainly in pines Pinus sylvestris L. The basal area of dead pines within the stand was the best predictor of cavity presence on sample plots. Our results confirm a key role of pine snags in natural coniferous stands. Forest management leads to dramatic reduction of tree cavity resources in managed stands. We suggest that the leaving or creation of pine snags is the most effective method of providing or retaining cavity resources in commercial coniferous forests in Europe.