318 THE STUDY OF PLANT COMMUNITIES * Chapter XII 



adapted. The situation in New England is illustrative. Here the 

 original forest has long been gone, and reforestation and silvi- 

 cultural programs have been in progress for some time. Introduc- 

 tions include Scotch pine, European larch, and Norway spruce 

 from Europe, and white spruce from the northern conifer forest. 

 Red pine and white pine have been grown at the fringe of their 

 range in pure stands on rich, heavy soils instead of the sandy soils 

 on which they naturally occur. 



The production of artificial forest types in New England can, 

 as a whole, be described as unsuccessful. S. H. Spurr and C. A. 

 Cline, 245 pleading for the application of ecological principles, say 

 that older trees are often of poor form, and growth is likely to 

 decline sharply in later years. Very few artificial stands have been 

 profitably brought to maturity. Furthermore, these types are 

 especially susceptible to damage— from insects and other animals, 

 from disease, and from the elements. Norway spruce is severely 

 attacked by the white pine weevil; exotic larch plantations may 

 be severely damaged by the porcupine and squirrel; red pine, 

 south of its natural range, is particularly susceptible to Tympanis 

 canker and to attacks by the European pine-shoot moth; crooked- 

 ness of Scotch pine has been attributed to frost damage; weevils 

 do more damage to white pine on heavy than on light soils. These 

 authors admit that eventually, if sufficient knowledge is acquired, 

 artificial types may be grown successfully. For the present, they 

 cannot be recommended for New England because of previous 

 lack of success, the risk involved, and the high cost of production. 

 Probably similar generalizations can be made for most of the 

 forest regions of North America but with less evidence because 

 there has not been as much experimenting elsewhere. Although 

 forest species have been successfully introduced into new areas, 

 as, for example, the eucalyptus into California, the results in New 

 England are suggestive that such experimenting might be of 

 dubious value and certainly would not yield the necessary in- 

 formation except at great cost over a long period of years. 



If only natural forest communities are to be the objective, there 

 are two general types to be considered. Silviculture is usually 

 given consideration only after the old forests have been destroyed 

 and, not uncommonly, after much of the land has been used for 

 agriculture and subsequently abandoned. Under these conditions, 



