A NATIONAL PLAN FOR AMERICAN FORESTRY 657 



of continental size, concentration of all research of all classes in 

 Washington or any other one place is obviously out of the question. 

 Some decentralization and the establishment of some field units is 

 called for. One vital organization question involved in the formula- 

 tion of objectives has therefore been the determination of what kind 

 or kinds of field units and how many of each should be established, 

 and what their general organizations should be. The establishment 

 of such field units is so far-reaching in its commitments as to time, 

 costs, and the character and volume of results that it has been abso- 

 lutely necessary that it be based on sound fundamental principles. 



One of the most important basic principles taken into account 

 has been the interrelationship and essential unity of all phases of 

 forestry and hence of the research upon which the forestry enterprise 

 must depend. For example, natural reproduction in ponderosa pine 

 stands on the Coconino Plateau in the Southwest depends partly 

 upon precipitation and other climatic factors. Abundant reproduc- 

 tion can be obtained only through the rare combination of an abundant 

 seed crop followed by a year favorable for survival of the seedlings. 

 Soil is another important and very complex factor, as is also competi- 

 tion of larger trees both above and below ground. In this particular 

 part of the range of ponderosa pine, damage to forest reproduction 

 from livestock grazing may be very severe and the conditions under 

 which it occurs and the grazing management necessary to prevent 

 it must be taken into account. Range use obviously depends upon 

 the character and amount of the forage or subordinate forest vege- 

 tion, and this in turn is frequently an important competitor of forest 

 tree seedlings. 



Campaigns for the destruction of predatory animals are carried 

 out to reduce losses of livestock, and apparently result in increased 

 numbers of rodents, some of which consume large quantities of forest 

 tree seed, others destroy small seedlings, others, such as porcupines, 

 destroy large seedlings, saplings, and even larger trees, and still 

 others feed upon forage plants. Game animals are related to forest 

 perpetuation on the one hand and to range use on the other. Both 

 range use and forest reproduction are definitely tied in to the necessity 

 and the ease or difficulty of fire protection. Both entomological and 

 pathological problems are almost inevitably involved in very complex 

 and far-reaching ways. The conditions, such as density of stand, 

 etc., under which timber is grown, have a very direct influence on 

 both the quantity and the character or quality of the forest products 

 produced. Any form of forest or range or game management modifies 

 natural conditions, and sets up a chain of biological sequences which 

 is likely to carry through the entire forest complex. And all of these 

 things are reflected in the requirements and nature of research. All 

 phases of management have their economic aspects, which in them- 

 selves are interrelated and which must also be reflected in research. 



Under the southern rim of the Coconino Plateau another group of 

 relationships and hence another class of forest research comes into 

 the picture the influence of vegetative cover on erosion and stream- 

 flow. The vegetative cover may be virgin or cut-over forest, or it 

 may be that which follows the timber on devastated forest land. It 

 may consist of chaparral or brush, or of forage grasses and other 

 plants in the subordinate vegetation, or of different combinations 

 of these. The brush and forage cover may have been materially 



