From my perspective as a Pistacia weinmannifolia, my natural growth habit is that of a large shrub or small tree, often with multiple trunks and a dense, rounded crown. My branches are strong, and my growth rate is moderate. When a part of me is pruned, I perceive it as a wound. I immediately initiate a compartmentalization process, sealing off the wounded area with chemical and physical barriers to prevent the spread of decay and pathogens into my healthy tissues. This is a costly process, consuming energy I would otherwise use for growth or defense. Therefore, clean, precise cuts made at the correct time and location are crucial to minimize the size of the wound and allow me to seal it efficiently.
The act of pruning should align with my biological needs for light, air, and structural integrity. Thinning cuts, which remove entire branches back to their point of origin, are highly beneficial. They open up my canopy, allowing sunlight to penetrate deeper and air to circulate more freely. This reduces humidity around my leaves, discouraging fungal pathogens, and ensures that my inner and lower leaves can photosynthesize effectively, making me a healthier, more vigorous plant. This also reduces weight on my limbs, preventing damage from wind or snow.
The timing of pruning is critical for my well-being. The ideal window is during my late dormancy, in late winter or very early spring, just before my new buds break. At this time, my energy reserves in my roots and wood are high, and I can rapidly mobilize resources to heal the wounds once growth begins. Pruning at this time also minimizes the risk of sap bleeding, which, while not fatal, is a loss of valuable resources. I strongly advise against heavy pruning in late summer or autumn. This stimulates tender new growth that will not have sufficient time to harden off before winter, making it susceptible to frost damage and dieback, weakening me significantly.
How you cut is as important as when and why. Each cut should be made with a sharp, sterilized tool. For smaller branches, make the cut just beyond the branch collar—the slightly swollen area where the branch meets the trunk or a larger limb. Do not cut flush against the trunk, as this removes the collar and destroys the tissues I need to form a proper callus and seal the wound. Conversely, do not leave a long stub, as this will die back and become an entry point for rot. For larger, heavier limbs, use the three-cut technique to prevent the bark from tearing down my trunk, which would create a much larger and more damaging wound.
When shaping my form, the goal should be to encourage a strong framework. This involves identifying and selecting a central leader or main trunks and removing competing leaders. Also, look for and eliminate narrow, V-shaped crotches, as these are structurally weak and prone to splitting. Instead, favor branches that attach to the trunk at a wider angle, as they form stronger unions. By removing crossing or rubbing branches, you prevent wounds that can serve as infection sites. The aim is to achieve a balanced, open structure that allows me to withstand environmental stresses and express my natural, attractive form.
