44 U. S. DEPARTMENT OF AGRICULTURE BULLETIN NO. 484. : 
only between the species in Mosher’s four EESESS but also between 
the different species in each class. 
Uneven-aged stands.—In uneven-aged stands a odi fied 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.’ 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 
50 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. 
1See table, p. 46. 
