A Type of Forest Management

By Thembi Borras

I did not leave college knowing how to practice sustainable forestry on the ground. In fact, if I had depended solely on what I had learned in college I would not have thought the type of forest management I have learned and been privileged to implement for the last seven years was viable because, in part, economic return is not maximized. The type of forest management that I now use is quite simple. First, establish a long-range sustained yield goal based on the productive capacity of the site and a reasonable growth rate. After the long range sustained yield goal is established, build inventory by cutting less than growth until the goal is met. Once the goal is met, growth can be harvested. The other aspect of this approach is to improve stand structure by not cutting the biggest and best trees.

Although short-term profit is not maximized this approach provides a periodic income to the landowner and is an effective way to support forest related values. Pre harvest habitat is the same as post harvest habitat, so wildlife habitat does not decline. Aesthetics are bolstered by maintaining a continuous forest canopy and encouraging fewer large stems as opposed to many small stems. Also, this type of forest management can minimize adverse watershed effects through the low level of canopy removal. The lower the level of canopy removal the lower the increase in peak flow. Conversely, an increase in peak flows can mean an increase in sediment production.

Other arguments against this type of forest management, which can be described as a light intensity single tree selection, are natural regeneration suffers due to lack of adequate light and reentry every 10 to 15 years does not allow the land to rest. While these arguments have some validity, they are not insurmountable. Redwood sprouting is usually adequate post harvest but it is sometimes necessary to remove trees in small groups to encourage Douglas-fir seedlings. In addition, seedlings can be interplanted in openings created by the harvest to supplement natural regeneration. Finally, periodic entry every 10 to 15 years is an opportunity to improve a permanent truck road and skid trail network and correct accessible legacy problems.

A portion of this production was gleaned from an unpublished paper by Craig Blencowe entitled, Craig Blencowe: Building up the Forest.