TABLE 3. — Constrained regressions through aggregated data points relating average bulk depth, y (inches) to average number 

 of intercepts of 1/4- to 1-inch debris fuel in two-crossed 2-foot sample planes, x 



: : Age of : : : 



Type of cutting : Dominant : debris : Sample included for data averaging : Regression results : Figure 



: species : (year) : Year Units : Equation "S" j reference 



Ground-lead harvest, 6-in top 



DF, 



mix 





1 



1975 



2, 



11, 13, 14 





y 



= 



3.16/x 



0.S6 





Ground-lead harvest, 6-in top 

 (slashed after harvest removed) 



DF 





2 



3 



1975 



7, 



8, 9 





y 



= 



3.22>/x" 



.87 





Ground-lead harvest, 6-in top 

 (slashed after harvest removed) 



DF 







1 



1975 



10, 



12 





y 



= 



3.18^ 



.86 





Ground-lead harvest, 6-in top 



DF 







3 



1975 



3, 



5 





y 



= 



3.4S/x 



.71 





Ground-lead harvest, 3-in top 



LP 





1 



3 



1975 

 1976 



23, 

 3, 



24, 25, 26; 



4 





y 



- 



3.03/x 



.88 





Ground-lead harvest, 6-in top 



DF, 



mix 



1 



2,3 



1975 



2,3 



,5,7,8,9,10, 



11,12,13,14 



y 



s 



3.27/x 



.93 



3 



Ground-lead harvest, 5-in top 



LP 







1 



1976 



23, 



24, 30 





y 



= 



4.5l/x 



.84 





Precommercial thinning 



PP 







4 



1976 



10, 



12, 13, 15, 



16 



y 



= 



3.56/x 



.92 





Precommercial thinning—'' 



LP 







4 



1976 



1, 



5, 6, 17 





y 





5.22/x 



.98 





Precommercial thinning 



DF 





3 



4 



1975 



4, 



15, 16, 17, 



18, 19, 22 



y 





4.75v / x 



.90 



1 



Precommercial thinning 



LP, 



PP 





1 



1976 



9, 



27, 28, 29, 



31 



y 





5.58/x 



.94 





High-lead harvest, 6-in top 



Mix 







1 



1976 



18, 



20,21,26,35, 



36,37,38,39 



y 





4.60/x 



.91 



2 



High-lead harvest, 6-in top 

 (lopped by harvest crew) 



Mix 







1 



1976 



14, 



19, 22, 25 





y 





3.60/x 



.96 





— These units are not typical of current practice, as trees of large d.b.h. were thinned. The relationship 

 developed was not used for model purposes for this reason. 



Figure 1. — Aggregated data 

 for bulk depth as a func- 

 tion of intercept count 

 (1/4- to 1-inch particles 

 per 4 feet of transect) 

 for precommercial thinning. 

 Analysis is shown in 

 table 3. 



INTERCEPT COUNT U -to 1-INCH PARTICLES) 



9 



