Growth and productivity of larch crops of different density in southern taiga of Central Siberia

• Published in: Сибирский лесной журнал
• Main Author: L. S. Pshenichnikova
• Format: Article in Journal/Newspaper
• Language: English; Russian
• Published: Russian Academy of Sciences, Siberian Branch Publishing House 2018
• Subjects: Larix sibirica Ledeb; planting density; age dynamics; forest inventory parameters; southern taiga; Krasnoyarsk Krai; Forestry; SD1-669.5; taiga; Siberia
• Online Access: https://doi.org/10.15372/SJFS20180103; https://doaj.org/article/abb89bcf79804be989ff9521c85bb0a6

This paper analyzes a 35-year experiment of growing Siberian larch Larix sibirica Ledeb. crops, planted at 18 variants of density in the southern taiga subzone of the Krasnoyarsk Krai. We discuss the results of regular observations of the tree growth and productivity in relationship with age carried out since the larch crops were planted. The differentiation of the trees started sooner and grew more intensive and self-thinning increased with increasing initial planting density, and the number of trees per unit area decreased with age. Mean tree diameter decreased with increasing planting density, whereas the influence of the density on tree diameter shifted toward initially sparser crops. The tree height showed a weak correlation with planting density. Over the period of observation, the standing volume has increased slowly for the lowest planting densities, slowed down in dense crops and decreased in the initially densest crops. The current tree increment culminated sooner with increasing planting density. The number of trees per unit area yielding the highest standing volume decreased with age. At the ages of 25, 30, and 35, maximum standing volume (400 m3/ha) was observed for current crop densities of 10 000 trees/ha, 7000 trees/ha, and 5000–6000 trees/ha, respectively. The crops, which were initially very dense, fell behind other crops in productivity with age. Therefore, very dense tree planting is unreasonable. The density, at which we would recommend to plant larch in southern taiga is 6000–8000 seedlings per hectare.