CHOICE OF ROTATION III 



Sugar Pine, Western Yellow Pine, Hemlock and Longleaf as cut for 

 lumber today are generally over 200 years old ; White Pine, Spruce, 

 Lodgepole and Cedar, also Oak, Yellow Poplar, Maple and Beech, 

 over 150 years old, and the rest of saw material generally over TOO 

 years. 



Using 12" d. b. h. as minimum size, measurements thus far 

 made would indicate for ordinary sites a technical Rotation : 



Of forty years and less (down to twenty-five years) for Cotton- 

 wood, Red Gum, Eucalyptus, Red Wood from sprout, also for 

 Maple, Elm and other timber on good soils like river bottoms, etc. 



Of 40-60 years for: 



' White Ash, Red Oak, Chestnut, Elm, Basswood, Cuban and 

 Loblolly Pine, and the following Pacific Coast trees, Red Fir, Hem- 

 lock, Spruce. Sugar and Western Yellow Pine. 



Of 60-80 years for : 



Norway Pine, Eastern and Western White Pine, Longleaf and 

 Shortleaf Pines of the South, Cypress, Red Fir of the Rockies, 

 Hickory, and Yellow Poplar. 



Of 80-100 years for: 



White Oaks and Western Balsams and Cedars in the mountains. 



Of IOO-T2O years for: 



Maple, Beech, Yellow Birch of Great Lakes Region and East, 

 Eastern Hemlock. 



Of 120-150 years for: 



Red Spruce, Tamarack, Lodge Pole and Engelman Spruce of 

 the Rockies. 



These figures are mere suggestions, and would be modified 

 within wide limits by the site covered, as well as methods used in 

 care of the forest, planting, thinning, etc. 



e. Furniture lumber and Tight Cooperage call for hardwoods 

 in larger sizes with fully matured heart wood where such decides 

 desirable color and other qualities. Here 18" d. b. h. may be set as 

 minimum. Tn central Europe, White Oak is grown to an age of 

 160-200 years and even older. Tt is doubtful if Rotations of over 

 150 years will be provided for in the future, since combination of 

 good soil and climate and relatively small yield tend to make the 

 raising of this class of timber unprofitable. In addition rapid exten- 

 sion of commerce with the tropics may make it unnecessary to 

 provide for much of this kind of timber in the future. 



