162 Forestry Quarterly 



for use. It does not give the impression of a growing crop neces- 

 sary to have the growth for which the enterprise is kept. It 

 misleads in so far as it ignores the very important non-merchantable 

 part of the growing stock (36% in the above case) without which 

 the whole business must fail. 



If, in the above case, the forester cuts all of the merchantable 

 material, i. e., the whole 64 per cent, and keeps the performance up, 

 he simply changes from a rotation of 100 years to one of 60 

 years, and if done well and the reproduction keeps pace, etc., he 

 changes his growing stock from that of a 100 year forest to that 

 of a 60 year forest. AU intermediates are possible. 



But if the rotation is set at 100 years and the growth is 700 

 feet the normal growing stock is fixed, and a forest in which the 

 forester cuts more than 40 per cent at his 20 year return is simply no 

 longer normal, but lacks in the volume element of the growing 

 stock. 



If, in this way, the growing stock per acre in above case is 

 reduced from 35 IvI. ft. to, say, 20 M. ft. per acre, the growth, too, 

 wiU be modified, in most cases reduced, both in quality and 

 vohome. 



But the forester might go on with this way of doing and even 

 be satisfied with it and speak of this actual, reduced growing stock 

 as a normal growing stock. If he does, the measure is gone and 

 any forest, regardless of conditions of age classes, volume and 

 quality may then, with equal propriety be called a normal forest 

 and its actual growing stock, a normal growing stock. 



How things appear in the usual wild woods, what is rotation, 

 Yr, growth, and G, and also what data might be used as Y^, 

 growth, and rotation when the natural rotation is reduced to a 

 man-made rotation, all this is interesting, but space forbids going 

 into this at this time. 



