MANAGEMENT APPLICATION 



The broadcast burning of moist fuels produces large variation in duff depth reduc- 

 tion and mineral soil exposure, even across relatively similar areas. Because mean 

 values were small, standard deviations for each consistently approached the means in 

 the clearcut, and exceeded them in the shelterwoods . Differences in variation were 

 found to be primarily within each block rather than between blocks. In addition, the 

 fires failed to heat or to dry the surface soil sufficiently to significantly reduce 

 the root sprouting potential of competing nonconif erous species. 



The hypothesis that the high water content of the duff influenced the expected re- 

 lationships is strengthened when weather patterns for the area are examined. Although 

 August 1975 was the coldest and one of the wettest on record, this combination of a low 

 temperature with heavy precipitation has occurred in this area seven times in the past 

 29 years. Because this situation occurs about one year out of four, the possibility 

 of extremely wet duff conditions should be considered when planning September fires. 



The lack of correlation between lower duff water content and percent duff re- 

 duction substantiates Shearer's (1975) and Norum's (1977) conclusions. Therefore, with 

 a mean lower duff water content of greater than 100 percent, broadcast burning for duff 

 reduction should probably not be attempted in this forest type. 



The burned areas revegetated quickly in 1976 from rhizomes, root crowns, and under- 

 ground stems. Growth was enhanced by the large supply of available nutrients released 

 during the fires. Trees and other vegetation relying on seed for regeneration were at 

 a competitive disadvantage because of the density of plants sprouting from underground 

 parts. Regeneration of shade-intolerant conifers will be difficult because of gener- 

 ally unfavorable seedbed conditions and intense competition for light and water. A few 

 western larch that germinated in 1975 survived within unbumed areas and will probably 

 form a part of the dominant tree canopy within a few years. It is doubtful that many 

 other shade-intolerant conifers will survive this competition. Gradually the more 

 shade-tolerant subalpine fir, western henilock (on lower slope moist sites) , and Douglas- 

 fir (on drier sites) will establish and complete a new stand. Later papers will discuss 

 (1) development of vegetation (including trees) within each cutting method and residue 

 treatment, and (2) effects of broadcast fires on residual trees. 



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