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JOURNAL OF FORESTRY 



upon the ratio of the volume of the thrown trees to that of the total 

 number of trees left standing at the time of cutting. 



Table 1. — Total number of trees throivn, volume of the trees, and tJie percent- 

 age of loss for each plot. 



" Estimated. 



The value of this table is that it shows in actual figures the total 

 volume of windfall loss for a long period of years and gives the per- 

 centage of the original reserved stand which this figure represents. 

 Plot I shows the heaviest loss in proportion to the stand left at the 

 time of cutting. On this plot nearly 45,000 board feet had been left 

 standing on 20 acres, and the volume thrown in 20 years was 10,745 

 board feet, or 24 per cent. On Plot II, where the next greatest pro- 

 portional loss occurred, 41,310 board feet had been left standing on 

 40 acres and the volume blown down in 15 years amounted to 8,995 

 board feet, or 22 per cent. The significant thing about these figures 

 is that the loss is not the result of exposure to one or two storms, but 

 of 15 and 20 years of exposure on bad windrisk sites. 



An apparent irregularity in Table 1 will be noticed, in that the heavy 

 volume loss on Plot III is represented as an exceedingly small loss in 

 per cent. This is explained by the fact that the plot was located in an 

 unusually heavy body of timber, which ran 30,250 board feet per acre 

 before cutting, and in which the logger cut only very lightly, leaving 

 fully 40 per cent of the original stand. In the case of the other plots 

 the stand before cutting averaged from 13,000 to 25,000 board feet 

 per acre. 



Table 2 shows, by half decades, for each plot, the number of trees 

 thrown since cutting. It also shows the percentage of total thrown 

 volume in each five-year period. 



