managi;ment of hardwood forests 289 



rious stands of timber are segregated and described as to location and 

 area. The areas are then studied carefully and divided into six or 

 more classes, depending upon the length of rotation adopted, as 

 follows : 



Class I — Main stand of timber, 1 to 20 years old 

 Class II — Main stand of timber, 21 to 40 years old 

 Class III — Main stand of timber, 41 to 60 years old 

 Class IV — Main stand of timber, 61 to 80 years old 

 Class V — Main stand of timber, 81 to 100 years old 

 Class VI — Main stand of timber, over 100 years old 



If the distribution of classes is normal, and the rotation is 120 years, 

 it is evident that all of the areas under Class VI should be cut during 

 the next 20 years, Class V during the following 20-year cutting period, 

 Class IV the next, and so on, but, unfortunately, the actual distribu- 

 tion seldom even approaches the normal ; there is nearly always a 

 heavy surplus of area under Class VI or Class I, or both, with a very 

 light representation of Classes, II, III, IV, and V. Clfiss V is fre- 

 quently entirely missing. 



The comparison of the actual distribution of classes with the normal 

 will indicate to the forester the points of attack in arranging the 

 stands in his schedule of periodic cuts. For instance, if the classifica- 

 tion shows a total lack of Class V stands, it may be necessary to extend 

 or spread the utilization of the Class VI stands over two 20-year 

 periods instead of cutting them in the current cutting period. In 

 deciding just which of the Class VI stands are to be set up as Class V, 

 the age and condition of the timber, the necessity and merchantability 

 of the stand, and the needs of local industry are taken into account. 



It will be hardly possible in any of the working circles to rearrange 

 or reclassify the stands so as to show a permanent, uniform annual yield 

 through an entire rotation, but this desirable end may be approached 

 quite closely for the next two cutting periods, at least on most of the 

 circles. When the various stands have been finally classified, as to 

 the period in which they should be cut, taking all factors into consid- 

 eration, the calculation of the cut per period is simply a matter of 

 estimating the amount of timber to be expected (present stand plus 

 increment) on the stands to be cut during that period. 



Summarized, the system is : Divide the forest into its component 

 stands : after studying the silvicultural needs of each stand and the 

 economic factors afifecting it, prescribe for its management. To ascer- 



