Скачать или смотреть Eucalyptus Gunnii Azura One Month After Prunning, Effect Of Auxin Hormones On Leading Main Branch

Pruning the main leader branch of a tree significantly impacts auxin distribution, affecting the tree's growth and shape. Auxin, produced at the growing tips, promotes cell elongation and apical dominance, meaning the terminal bud (top of the leader) inhibits the growth of lower buds. Removing the leader disrupts this balance, releasing lateral buds to grow and potentially leading to a bushier form or the development of new leaders. 

Here's a more detailed explanation:

Auxin and Apical Dominance:

Auxin, primarily produced in the terminal bud of the leader, suppresses the growth of lateral buds below it. This creates a hierarchical growth pattern where the leader is the most dominant and vigorous part of the tree. 

Pruning the Leader:

Removing the terminal bud (and thus the source of auxin) releases the lateral buds from suppression, causing them to grow more actively. 

Consequences of Pruning:

New Leaders: If the tree is young and the pruning cut is high, one or more lateral branches may emerge and compete to become the new leader, potentially creating a multi-leader or less desirable shape. 

Bushier Growth: In some cases, especially with shrubs or trees where a bushier form is desired, pruning the leader can encourage more lateral branching. 

Slower Upward Growth: Removing the leader can slow the tree's upward growth and reduce its overall height. 

Pruning Techniques:

Formative Pruning: This involves removing competing upright branches or shortening side branches to encourage a strong central leader and well-spaced branches. 

Subordination Pruning: This technique involves reducing the height of one of two co-dominant stems to encourage apical dominance in the other, preventing a weak or split trunk. 

Timing and Technique:

Early Pruning: Formative pruning of young trees is important for establishing good structure and shape. 

Cut to Outward-Facing Buds: When pruning, cut to outward-facing buds to encourage outward growth and prevent branches from growing into the center of the tree. 

Consider the Tree's Species and Desired Shape: Different tree species have different growth habits. Some may naturally develop a central leader, while others may be better suited to a more spreading form.