338 FOREST INDICATORS. 



stable formation, i. e., a forest type and a stable formation of a succession are 

 identical. This identity is made clearer by the author's insistence upon 

 stability as the ideal for which the forester must strive in regenerating and 

 caring for his forest. The change in stabilization is perhaps the most essential 

 feature of a succession, and the succession terminates only because the habitat 

 is finally occupied by a formation which, accidents excepted, is best suited 

 to it and hence is permanent. " 



The varying concepts and applications dealing with the forest type are well 

 illustrated by a symposium on the subject, the papers of which are briefly 

 abstracted here. Dana (1913: 55) defines the different kinds of types which 

 seem to serve a useful purpose and should be recognized : 



"A forest type, known often as simply a type, is a stand of trees with dis- 

 tinctive characteristics of composition. A cover type is a forest type now occu- 

 pying the ground. The term conveys no implication as to whether the type 

 is temporary or permanent, or one which we shall strive to maintain under 

 forest management. A temporary type is a forest type which has come in as 

 a result of some interference with natural conditions, such as fire or lumbering, 

 and which will eventually, if nature is left undisturbed, be replaced by a 

 different type. A permanent type, or natural type, is a forest type which will 

 eventually take possession of and perpetuate itself on any given area if natural 

 conditions are undisturbed. A management type is a forest type that we shall 

 strive to maintain under forest management, irrespective of whether or not 

 it is the type that would occupy the area under natural conditions. " 



Munger (1913: 62) emphasizes the following point: 



"The term forest type must above all be used for a classification of timber- 

 land that will be useful to the practicing forester in forest management in a 

 broad sense. Forest typing must not merely be a theoretic grouping of simi- 

 lar areas convenient for wall-map purposes or a classification of merely botani- 

 cal or ecological interest. Their distinctions must be based on fundamental 

 points of difference which have significance to the forester. In every form of 

 intensive reconnaissance which a forester is doing preparatory to making 

 working plans, he should include the collection of data showing both the 

 present composition by species and the physical conditions of the site. 

 Though both of these classes of data may be shown on his maps, I feel that 

 the term 'forest type' should be reserved for a classification based upon per- 

 manent basic physical factors. I should define, therefore, a forest type as an 

 aggregation of areas of forest land upon which the physical conditions of 

 clipiate, soil, and moisture are so similar that an identical form of silvicultural 

 management may be applied on all." 



Woodward (1913:69) states: 



"In the examination of lands offered for purchase under the Weeks law, it 

 has been found desirable to classify the kinds of forest stands and sites from 

 two points of view. In the first place, it is necessary to know the composition 

 of the present stands in order to arrive at the value of the timber. The second 

 way in which sites need to be classified in valuing the lands offered is to de- 

 termine the value of the site for producing timber. In a virgin stand, the 

 present composition is a very good index of what can be grown on the area in 

 question. However, it is conceivable that under forest management it may 

 not be advisable to wait for the struggle for existence to proceed so far that 

 temporary species are eliminated. As a means of classifying stands and sites, 



