Stand Tending

Stand tending is a subset of silviculture that includes a variety of forest treatments, including pre-commercial thinning, fertilizing, pruning and commercial thinning, which are carried out to maintain a healthy forest and to increase the quality and quantity of timber produced.

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Forest Fertilization

Although other silviculture treatments may redistribute volume and/or increase piece size and value, fertilization is the most proven method for increasing harvest volume and accelerating the operability of established stands. As such, fertilization is widely viewed by forest managers and practitioners as a potentially valuable tool for mitigating "pinch points" in the mid-term timber supply caused by age class imbalances, and for increasing long term harvest levels.


Pruning of lower branches of trees in plantations and in pre-commercially thinned stands can increase stand value by reducing the size of the knotty core, thereby increasing the amount and proportion of more valuable clear (knot free) wood. Dimensional lumber that is "clear" of knots and defects has historically commanded premium prices on world markets. Pruning may also improve log and lumber value by speeding the change from lower value juvenile wood to higher value mature wood and by reducing stem taper.

Pre-Commercial Thinning or Spacing

Terminology such as "juvenile thinning," "juvenile spacing," "spacing" and "pre-commercial thinning" generally refers to cuttings made in immature stands with the objective of reducing stand density in order to stimulate the growth of the remaining crop. Thinning affects the size and growth of individual trees and also the growth per unit area of the stand itself. The timing and intensity of juvenile thinning has large potential impacts on the amount, size and value of timber harvested from managed forests and on biological and technical rotation lengths. By preventing, or alleviating, height repression, juvenile thinning in extremely dense stands may provide a more reliable estimate of site potential as represented by site index.

Commercial Thinning and Partial Cutting

Commercial thinning is a partial cutting treatment applied to immature forests where the value to the province exceeds the cost of the treatment.  Commercial thinning applies to even-aged forest stands and is an interim treatment that exists in the context of a broader stand management regime to provide for specific prescribed stand volume and value attributes over time.  Value may be economic as a measure of quality and quantity of fibre in the future, providing ecological function or social in nature as a steady flow of fibre for producers.

Commercial thinning (CT) may help offset short- and mid-term timber supply shortfalls experienced in some Interior management units (e.g., Timber Supply Areas and Tree Farm Licences) by providing redistribution of timber flow at the landscape level by breaking up large areas of THLB in similar age classes.  There is also a societal focus on the health, condition, and overall resilience of our forests and CT may contribute to this goal.