xlviii APPENDIX. 



trees the best one is kept and the worst marked for felling. The 

 guard marks the trees to be removed and a gang of coolies working 

 with him cuts them down. ' The stick may be of any length 

 ordered but for sapling crops under 6' diameter, to which crops 

 alone this method is intended to apply, a 4 foot stick is recom- 

 mended for conifers and a 3 foot stick for sal. The final spacing 

 of the trees left standing will be about 1| times the length of the 

 stick used. Extensive areas of various species have been thinned 

 in this way in many divisions of Northern India and the method 

 can be recommended with absolute confidence. 



It has been stated that thinnings are undesirable or unneces- 

 sary in the case of uil ; a mass of figures go to show however that 

 thinnings in nal are absolutely necessary if a reasonable rotation 

 and increment is to be maintained. Two plots in Haldwani 

 have been under observation for 28 years. One was never thinned 

 and the other was thinned once in 1884 and never again. The 

 increment for the first 50 trees in each plot (stretching from 18* 

 to 60'' girth) shows 



For unthinned plot = 7" 5" per tree. 



For thinned plot =13 "7" per tree. 



Assuming this rate of increment spread over the rotation (and 

 the large difference in limits of girth in each plot makes this 

 justifiable) it shows that in 120 years 



An unthinned crop would attain 2' 8" girth. 



A thinned crop would attain 4' 10'' girth. 



How much more the latter increment would have been accelerated 

 by subsequent regular thinnings is proved by the slowing down of 

 the increment curve of this plot while neighbouring regularly 

 thinned plots show accelerated increment for every thinning. 

 Exactly similar results are shown by the two Chaukhamb sample 

 plots in Lansdowne, situated side by side and measured annually 

 since 1902. The thinned plot only had one thinning in that year 

 and the immediate stimulus to increment is at once apparent from 

 the graph attached Plate 13. The old Dehra Dun sample plots 



