200 



GROWING BETTER TIMBER 



ARTHUR KOEHLER 



The man who grows trees for timber 

 will do well to remember that as the 

 twig is bent the tree is inclined. He will 

 find that he can guide natural processes 

 and improve on them. With a purpose 

 like the one watchful parents and 

 teachers have with young people, he 

 can straighten out deficiencies in tree 

 growth by his proper management of 

 young stands of timber, which, if left to 

 follow their bent, make inferior wood. 



He knows less about the possibilities 

 of improving on nature in growing 

 timber than he does about agricultural 

 crops. But because many of the pres- 

 ent second-growth stands still are in 

 the formative stage and all future 

 stands will be so, his opportunities for 

 improving the quality of the wood in 

 such stands are many. As a rule, second- 

 growth forests (that is, young forests 

 that develop after the old, virgin 

 growth is removed) are smaller when 

 they are cut, have more taper, produce 

 a smaller proportion of knot-free wood, 

 furnish little quarter-sawed lumber, 

 and their individual boards vary more 

 in width and density than old-growth 

 timber. 



Furthermore, although intensive cul- 

 tural methods to improve the quality of 

 the crop may not be so well justified 

 for forest as for agricultural products, 

 the difference in value between timber 

 of poor quality and timber of good 

 quality is so large that net profit and 

 the usefulness of forest products can be 

 enhanced by judicious timber-growing 

 practices. 



The first question is: What quality 

 of timber are we going to want when 

 the crop is mature in 25 to 100 years? 



Sawlogs and veneer logs generally 

 will be the chief products, in volume 

 and value, of commercial forests for 

 generations to come, because timber, 

 lumber, and veneer have certain out- 

 standing characteristics unequaled by 

 other materials comparatively low 



cost of manufacture, ease of working, 

 ease of fastening with nails, screws, and 

 glues, light weight coupled with ade- 

 quate strength in appropriate sizes for 

 many uses. It is likely that coarse-fiber 

 products (insulating boards, sheathing 

 boards, hard boards, and papers for 

 fiberboard-box manufacture) will find 

 a wider future use than now ; for them, 

 however, we should be able to get a 

 large part of the raw material from 

 thinnings, forest residues, low-quality 

 wood, secondary species, and offal from 

 the major wood-utilization processes. 

 Timber, ties, poles, and most lumber 

 and veneer products will still require 

 natural wood of good quality. 



What kind of trees do we want for 

 timbers, lumber, and veneer? 



IN THE FIRST PLACE,, they must have 

 adequate size in order to be converted 

 and used profitably. In the future, that 

 size probably will be somewhere be- 

 tween 12 and 24 inches in diameter. 

 It may not be profitable to grow trees 

 4 feet in diameter on a commercial 

 basis because it takes too long. But 

 size is only one consideration. Fully as 

 important are the form of the tree 

 trunk and the defects and quality of 

 the clear wood that it contains. 



A valuable quality in trees for saw- 

 logs and veneer is straightness and up- 

 rightness of the trunk. Crookedness in 

 logs reduces the amount of lumber and 

 the maximum size of timbers that can 

 be cut from them and also causes warp- 

 ing of sawed products in drying, dif- 

 ficulty in getting a smooth surface, 

 and, because of the cross grain that ac- 

 companies crookedness low strength. 



Leaning tree trunks usually are 

 curved up or down. They also produce 

 abnormal wood in softwoods, on the 

 lower side, where it is known as com- 

 pression wood; in hardwoods, on the 

 upper side, where it is known as tension 

 wood. M. Y. Pillow, in his investiga- 



