Figure S. — Stocking percent and 

 number of trees per acre 

 (all species, advance and 

 subsequent) 6 years after 

 treatment . 



100 



90 



80 



70 



60 



O 50 



o 



O 40 

 CO 



30 



20 



10 



CONTROL 





//// 



Percent of stock ing 









Nu 



Tiber 

 V/A 



of trees 















% 





Y/// 





















P 





















































i 





i 







i 



















W/ 

 1 











i 















■ 



i 

















1 















1 







p 







P 













i 









i 



















r 







i 







BURN 



LIGHT MODERATE HEAVY 



5,000 



4,000 



UJ 

 DC 

 O 

 < 



3,000 £ 

 a. 



CO 

 UJ 



ai 

 cc 

 H 



2,000 



o 



DC 

 LU 

 CO 



1.000 



V 



SCARIFICATION 



percent on the control plots to 89 percent on the area most heavily scarified (fig- 3). 

 Since a 4-milacre stocking of 65 percent has customarily been considered adequate in 

 this region, the gross stocking of reproduction reached satisfactory levels in all 

 treatments. On the other hand, the number of trees per acre were quite markedly affected 

 by treatment. Both the control plots and the burned areas were well stocked with sur- 

 prisingly few total trees per acre; this indicates good distribution with a minimum of 

 clumping. 



From the standpoint of future merchantability, advance reproduction of subalpine 

 fir, mountain hemlock, and even Engelmann spruce may have questionable merit because 

 of poor form and susceptibility to rot. There is some question as to what extent these 

 trees can contribute to establishment of a productive new stand; however, such contri- 

 bution would certainly be highly variable. Widespread injury to advance growth fre- 

 quently accompanies logging and supplemental site preparation measures. This injury 

 provides many opportunities for rot infection among susceptible species. Day and Duffy 

 (1963), for instance, estimated that only 7 percent of the advance subalpine fir and 

 spruce reproduction had "good potential" in southwestern Alberta cutover stands. On 

 the other hand. Roe and Schmidt ^ in a survey of logged areas in southern Idaho, western 

 Wyoming, and Utah, found that an average of 37 percent of advance subalpine fir and 

 60 percent of advance Engelmann spruce had "good management potential." 



There is some doubt also as to the future economic value of subalpine fir and 

 mountain hemlock, even when free from early suppression and injury. Because of their 

 susceptibility to heart rot and because of the low values attached to these species in 



Roe, Arthur L. and Wyman C. Schmidt. Factors affecting natural regeneration of 

 spruce in the Intermountain Region. Unpublished manuscript, Intermountain Forest and 

 Range Exp. Sta. 



5 



