THE NORTH SLOPE FOREST 

 IS IN A STATE OF RAPID ATTRITION 



Were it not for the fact the North Slope timber is predominantly mature and over- 

 mature and that stand conditions have been aggravated by past cutting and fire protec- 

 tion practices, management decisions for the area could be deferred. Because more than 

 half of the conifer timber is mature or overmature, the North Slope lodgepole pine has 

 been under intermittent siege by mountain pine beetles for several decades. The most re- 

 cent flareup began in the Hole-in-the-Rock area in 1956 and spread westward to the Blacks 

 Fork River drainage. During this epidemic 165,000 acres were heavily attacked by beetles 

 (fig. 8). 



THE PROBLEM: TOO MANY EXISTING YOUNG 

 STANDS FAIL TO ACHIEVE THE POTENTIAL 

 OF THE LAND. 



GOOD 



GROWING — ■ 

 STOCK 



STAGNATED 



2% 



POOR GROWING STOCK 



These present stands lack vigor 

 and although some may reach 

 sawtimber size they will never 

 produce the full potential 

 volume of the site. Moreover, 

 there is no economical way to 

 improve their yields v«th 

 cultural work. 



Figure 



MOUNTAIN PINE BEETLE INFESTATION ON THE NORTH SLOPE 



AREA INFESTED BY 

 MOUNTAIN PINE BEETLE, 1961 



Figure 8 



A large-scale program to contain the infestation was begun in 1958. Up through 

 1962, $3.2 million was spent in this effort, which was successful to the extent that the 

 beetle population has been held approximately at a normal endemic level since 1963 (figs. 

 9 and 10). 



Whatever reduction in insect numbers has been caused by cyclic changes and control 

 programs, the respite must be regarded as only temporary. Forty-four percent of the 

 201,000 acres of mature and overmature timber is classified as "high risk" (table 7). Un- 

 til this timber is logged or killed, periodic fiareups of the mountain pine beetle and other 

 insects must be expected. 



9 



