Table 3 .--Density of seed dissemination, established seedlings, and stocking per acre 

 3 years after dissemination for seed-tree and shelterwood plots on the Boise 

 Basin Experimental Forest, 1958 







Seed-tree plot 







Shelterwood plot 







: Seed 





Seeds 



: Seed 





Seeds 



Scarifying 



: per 



Seedlings : Stocking 



per 



: per 



Seedlings :Stocking 



per 



tool 



: acre 



per acre percent 1 



seedling 



: acre 



per acre: percent 



seedling 



Land-clearing 



202,000 



3,476 87 



58 



255,000 



4,690 90 



54 



blade 















Disks 



33,120 



304 42 



109 



172,560 



1,360 72 



127 



Stocking percent = percent of 4-milacre quadrats containing at least one seedling. 



that 8 to 12 dominant trees 16 to 24 inches dbh will provide enough seed for regenera- 

 tion in an average seed year. Reserving this larger number of trees also makes 

 subsequent logging of the seed trees more economical. 



Single-tree and group selection. — The selection method (otherwise called selective 

 cuttings, or selection logging, partial cutting) has been employed in the West and in 

 the Intermountain Station territory more commonly to cut ponderosa pine than any other 

 method. Unfortunately, the selection method is subject to a wide variety of inter- 

 pretations. Textbooks describe the selection method as harvesting the oldest or 

 largest trees in a stand at repeated intervals throughout the rotation (Hawley and 

 Smith 1954). The objectives of the cuttings are to create uneven-aged stands and to 

 regenerate such stands. Most selective cuttings in ponderosa pine forests were not 

 designed to meet fully the objectives of the selection method; rather, they were 

 planned to remove individual trees or small groups selected on the basis of one of 

 several criteria including tree vigor, susceptibility to insect attack, and economic 

 value. Although application of selection cutting has varied, the values of the method 

 have been seen as twofold. First, it was a compromise between clearcutting and 

 leaving the stand untouched, maintaining reserve volume as growing stock that would 

 provide high net increment per acre in the residual stand. Second, the reserve trees 

 would provide a seed source, a reservoir for the future. As an added advantage, 

 the method demonstrates to the public that foresters are not stripping cover from 

 watersheds and ruining the beauty of the countryside. A real disadvantage is, how- 

 ever, that unless the cutting is designed with skill and understanding, the result 

 can be the high-grading of a stand, so that it consists of low-quality trees after 

 cutting. 



Some ponderosa pine stands appear to be all aged. Usually these consist of two or 

 three separate age classes, but include all crown classes because trees have developed 

 unevenly over a long period of time. Selection management with a long rotation is pos- 

 sible in these stands if the early cuttings are made carefully to develop the size 

 classes needed for future cutting cycles. A rotation of 160 to 200 years is necessary 

 because both tree growth and regeneration are slower under these conditions. Natural 

 reproduction is established only by an infrequent good seed crop followed by a growing 

 season with favorable weather. The selection system has the advantage of maintaining 

 a continuous stand of timber that is esthetically pleasing and protects the sites. 



Because early single-tree selection cuttings varied in purpose and execution, they 

 are difficult to evaluate. Reproduction establishment was greater after cutting than 

 before in one of these early cuttings in western Montana (Boe 1948) ; volume of the 



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