44 U. S. DEPARTMENT OF AGRICULTURE BULLETIN NO. 484. 



only between the species in Mosher's four classes, but also between 

 the different species in each class. 



I 'tie vein-aged stands. — In uneven-aged stands a modified form of 

 the selection system should be used, cutting to a diameter limit of 

 approximately 12 to 14 inches, which limit, however, should not be 

 strictly applied. 



Of course, the same treatment can not be applied to even-aged and 

 to uneven-aged stands. The stand now under discussion is of the 

 latter form, which will be first considered. 



The selection system may be briefly explained as follows: It is 

 the reverse of the clear-cutting systems already described as appli- 

 cable to stands like those at Dover, Exeter, Wareham, and Medfield. 

 The whole area remains continually covered with trees which, when 

 all ages and sizes are represented, mingled singly or in groups, are 

 called a selection forest. 1 In the selection system of cutting and 

 securing reproduction the cuttings are made annually or at longer 

 intervals, the mature trees being selected and those not mature left. 

 To maintain a stand indefinitely under this system it is essential that 

 no more trees be cut than will equal in volume the growth of wood 

 put on by the whole stand in the year or other interval between cut- 

 tings. 



In managing old, uneven-aged stands which have not previously 

 been under management, one of the first steps is to decide upon the 

 approximate rotation to use, for example, 100 years, and then to 

 remove as far as is possible, without 'making too large openings in 

 the crown cover, all trees too large to be grown in that length of 

 time. 



In stands like the one under discussion it would be well to do this 

 and also, in the first cutting, to eliminate red oak and reduce as much 

 as is possible, with due regard to silvicultural considerations, paper 

 birch and other intolerant species of Class I trees, which form a very 

 small percentage of the stand and can not maintain themselves in 

 stands with a large percentage of tolerant trees. The cuttings should 

 each be accompanied by a thinning, removing all dead, dying, defec- 

 tive, or suppressed trees, regardless of their species, but leaving any 

 the removal of which would expose the ground too much. The 

 selection cuttings and thinning combined may remove as much as 

 HO per cent of the original stand, leaving about 200 trees per acre. 

 In this stand the result upon each size class present is shown in the 

 table on page 46. The result upon the representation of each species 

 appears in the following table. 



i See table, p. 46. 



