DISCUSSION AND CONCLUSIONS 



It seems evident that both prescribed broadcast burning and mechanical scarification 

 have their place as aids to the establishment of natural regeneration in the larch-fir 

 type. Burning has the advantage of being usable over a wider range of topographic 

 conditions. It also seems to create conditions more favorable for obtaining acceptable 

 stocking with fewer seedlings, thus reducing future expenditures for cleaning and thin- 

 ning. If advance growth is considered undesirable, burning will more effectively 

 eliminate it from the future stand. IVhile valid direct comparisons of site preparation 

 costs are difficult to make, USDA Forest Service Region 1 cost analyses currently show 

 that site preparation by machine-piling, scarification and pile-burning is, on the 

 average, 25 percent more costly than slashing and Drescribed burning.^ 



Machine scarification has the advantages of being flexible enough to: (1) permit 

 preservation of much of the advance growth as part of the future stand while creating 

 favorable conditions elsewhere for subsequent reproduction; and (2) permit better timing 

 of the site preparation to take full advantage of natural seed dispersal without fear of 

 destroying part of the important first seed crop. Risks to men and adjacent timber are 

 likely to be less with bulldozer scarification than with prescribed broadcast burning. 



Probably the most difficult decision facing the timber manager occurs when suitable 

 advance growth is present. Then, it is not a choice between burning or scarification, 

 but whether to rely on the advance growth at no additional establishment cost, or to 

 prepare the site for new reproduction. Should the advance stand have a reasonably good 

 future after logging, it may be unwise to spend money to destroy it in favor of new 

 reproduction. It would seem that additional research is needed to help develop stand- 

 ards for appraising the production potential and management requirements of stands with 

 a large component of advance growth. 



Although the site preparation in this study did not appreciably improve the stocking 

 levels, it certainly increased the diversity of stand components and, consequently, the 

 diversity of management opportunities. Where no special site preparation was applied, 

 the reproduction stand was composed predominantly of advance subalpine fir and mountain 

 hemlock; such a stand tends to become highly defective and provides rather limited 

 alternatives for future management. Burning or scarification have increased these 

 management alternatives by providing stands composed mainly of subsequent reproduction 

 of the same three species plus an important addition of western larch and a small amount 

 of Douglas-fir and grand fir. Furthermore, the broader species' mixture may permit more 

 efficient utilization of the site and provide a stand which is less susceptible to 

 serious damage. 



Personal communication, USDA Forest Service Region 1 Division of Timber Management. 



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