EXPERIMENTS IN THINNINGS, 495 



C. Unthinned area. 



Experiment IV. 



Made on direct sowings of spruce effected in furrows 85 centi- 

 metres broad and 1 metre 70 centimetres apart ; leaf-canopy com- 

 plete, if we except three spots in area A where snowbreaks resulted 

 in small interruptions. First thinning made at the age of 40 years, 

 four subsequent thinnings at intervals of 5 years. 



A- Heavily thinned area. 

 Standing stock at 40 years ...212-75 139*49 352-25 



Yield of Windfalls ... 42-78 11-95 54-73 



Thinnings ... 107'76 67*29 175-05 



Standing stock at 60 years ...404-69 126-40 531*09 



Total production up to 60 years ... 555*23 205*64 760'87 

 Increase since the age of 40 years ... 342*48 66'15 408'63 



B. Moderately thinned area.. 

 Standing stock at 40 years ...209-43 135*59 345-02 



Yield of Windfalls ... 29'88 7'98 37*86 



Thinnings ... 78'03 54*35 132-38 



Standing stock at 60 years ...367-52 91*42 458*94 



Total production up to 60 years ... 475*43 153-75 629-18 

 Increase since the age of 40 years ... 266*00 1H-16 284*16 



