count gives an estimate of the total number of seedlings per acre. When considered 

 together, these values characterize the distribution and density of the reproduction 

 stand. Only "established" seedlings, 3 years old or older, were recorded. 



A 4-milacre stocking of 65 percent has, for many years, been the criterion of 

 adequate stocking in the western white pine type (Wellner 1940) . This is the standard 

 used in this report and is equivalent, in the average seedling stand, to about 1,000 

 trees per acre or to a 1-milacre stocking of 40 percent. 2 



INDIVIDUAL STUDY AREAS 



Ames Creek: Alternate Shelterwood and Clearcut Strips 



Description 



Following the leads from examples of successful strip-clearcutting dating back to 

 1910, this 36-acre area on a northeasterly exposure in the Thuj a-Tsuga/Pachistima 

 habitat type was horse-logged in 1935. Two clearcut strips, 4 to 7 chains wide, 

 alternated with three shelterwood strips 4 to 5 chains in width (fig. 2). Unmerchant- 

 able timber on the clearcut strips was felled in 1935 and 1936 following logging; 

 slash on these strips was control-broadcast-burned in 1936. 



The shelterwood cutting removed 60 percent of the 53,000 board feet per acre and 

 left a stand averaging 31 trees per acre. Of these trees, about 27 were western white 

 pine. This residual stand admitted 70 percent of full sunlight to the forest floor. 

 Unmerchantable trees were felled and the slash progressively burned in the spring of 

 1936. By 1951 the area was adequately regenerated and the remainder of the shelterwood 

 stand was "jammer" logged. 3 



Regeneration on this tract was influenced somewhat by a stand of mature timber that 

 was on the western border of the upper portion. Undoubtedly, seed from this stand, 

 which was not cut until 1952, was cast into the clearcut and shelterwood strips along 

 with seed from the shelterwood residual. 



Results 



Shelterwood strips . --Regeneration within the shelterwood strips was very prompt and 

 the distribution quite uniform (fig. 3). Four years after logging the 4-milacre 

 stocking to all species was over 60 percent with 548 seedlings per acre. Eight years 

 after logging the stocking had increased to 97 percent with 6,126 seedlings per acre. 



Although the shelterwood stand contained no hemlock, this species was by far the 

 most abundant in the reproduction. Some trees were advance growth, but the majority 

 were seedlings originating from seed dispersed into the area from adjacent uncut stands. 

 Western white pine was second in seedling representation with a 4-milacre stocking 



^Present regeneration examinations of the Northern Region of the Forest Service 

 are based on 1/300-acre sample plots. By their standard a "minimum acceptable stand" 

 would have at least 100 trees of crop-tree quality per acre, and a "desirable stand" 

 would require at least 250 crop trees. Assuming only one crop tree per stocked plot 

 and applying conversions developed by Lynch and Schumacher (1941) , the "minimum accept- 

 able stand" would be equivalent to 38 percent 4-milacre stocking or about 210 trees per 

 acre. The "desirable stand" would be equivalent to a 4-milacre stocking of 85 percent 

 or about 3,000 trees per acre. 



3 "Jammer" logging is a portable cable system utilizing a mobile boom 25-30 feet 

 long. Maximum skidding distances are 400 to 600 feet. The system is operated with or 

 without a haul-back line. 



3 



