Abstract:

As technologies become more precise to deal with each aspect on silviculture, great attention has been putting on the root pruning which is viewed as the most important root culturing. In this paper, root pruning includes bud-seedling root pruning, post-seedling root pruning, and table pruning. Post-seedling root pruning is divided into undercutting, wrenching, lateral pruning and box pruning. For each type, effects of root pruning on the morphological attributes, physiological attributes and field performance was reviewed. When Pinus radiata, characterized by a carrot-like taproot tree species, is severed by bud-seedling root pruning, undercutting and wrenching, a loss in apical dominance in the entire root system was caused. Following that shoot growth is arrested, lateral root growth increases, a more compact and fibrous root system develops, and shoot-root ratio decreases. These are attributed to the field performance especially in the arid areas. Slower growing evergreen species such as Pseudotsuga menziesii tend to have a more fibrous root system than P. radiata. Results from root cutting of the species have been more variable. Although hormones, mineral nutrition, carbohydrate, water in the seedlings were responded to root pruning, mechanism of seedling quality regulated by root pruning was inconsistent.

Key words: bud-seedling root pruning, undercutting, wrenching root, seedling quality, field performance