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1 Definition of a Silvicultural System 4 The Decision Process Appendix 1 Answer Key
2 Major Types of Systems 5 There's More to Learn Appendix 2 Advantages and Disadvantages
3 Variations of Major Types 6 Implementation Appendix 3 References

Big-tree Selection?

After World War II in British Columbia some controls were placed on harvesting in the Southern Interior. The BC Forest Service brought in the 60/40 rule, which dictated that only 60% of a stand could be harvested, while 40% must remain uncut. The rule was imposed by cruising stands to be sold, developing stand and stock tables, and devising a diameter limit to conform to the 60/40 rule.

What this meant was that all the trees above a given diameter were harvested leaving the smallest trees to make up the 40% uncut portion: in effect - "big-tree selection." While the BC Forest Service experimented with some highly commendable marking guidelines in the 1950s, the high cost of marking prompted a return to the diameter limit approach, which was much easier to monitor.

The end result was no different than the exploitive selective logging which only removed the most desirable trees. Stands were logged and left to languish in a much poorer condition than before harvesting, with overstocking of small, non-vigorous, often poorly formed, and unhealthy trees. Selection systems demand diligent care and attention to maintenance of stand structure, health, and vigour over the long term. The many volume-based tenures in place throughout the Southern Interior do not provide this long-term focus at the stand level andmake successful application of selection systems difficult. However, big-tree selection is not a silvicultural system and should have no place in forest management.


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Sad But True

Perverted applications of the single tree selection system in thewrong situations have left adisreputable legacy in the minds of many. A body of broad generalizations and misconceptions has provided thefirst operational hurdle to successful application of selection management: a poor attitude.
Rolan Becker (1995)

Although classical uneven-aged stands are great places to learn about uneven-aged management sometimes you have to make it work (or start to work) when the existing stand structure isn't totally cooperative. That's when following the textbooks gets tough. That's when experience counts.
Mike Znerold (1990)