SAMPLE PLOTS IX SILVICULTURAL RESEARCH 87 



A secondary and incidental but hardly less important purpose is to provide 

 for the demonstration of results, favorable and otherwise, of widely varying 

 silvicultural and other forest practices. 



Assured provision for the best possible field laboratories for research is so 

 vital to sound national-forest administration and to the development of private 

 forestry that the selection of necessary areas is made a part of Forest Service 

 policy and procedure under mandatory instructions from the Secretary of 

 Agriculture. 



NUMBER, CHARACTER, AND EXTENT 



The McSweeney-McNary Forest Research Act specifies 12 or 13 forest regions 

 in the United States proper, in each of which a forest experiment station is to 

 be established. So far as can now be foreseen, from 5 to 10 experimental 

 forests will ultimately be required in each region, with an average of about 

 eight. The area of each of these forests should range from about 1,500 

 acres as a minimum to about 5,000 as a maximum, and average about 3,500 

 acres, exclusive of natural areas. They should be large enough to provide ade- 

 quately for present and foreseeable future work. They should be small enough 

 to avoid all unnecessary burden of administration. Size should be governed 

 primarily by the complexity of the type and the growth rate of tree species. 

 The simpler the type and the higher the growth rate the smaller the area that 

 will be required. 



Each experimental forest should be as fully representative as possible of 

 the conditions in important subregions. More specifically, this means ade- 

 quate representation of forest types and sites, of the conditions which under- 

 lie types and sites, such as soils, climatic variations, altitudinal range, etc., 

 and of the older age classes particularly. Accessibility is an important con- 

 sideration, for the marketing of forest products to permit intensive silvicultural 

 experimentation, and for ease of access to visitors and to the investigative staff. 



Accessibility may require both satisfactory automobile roads, and railroads 

 or drivable streams. Assurance of protection against fire may also be a 

 factor of importance in location because the cumulative investment of large 

 numbers of investigative projects will soon far exceed the intrinsic value of 

 the timber stand itself. 



Where it is not possible to find a satisfactory representation of conditions 

 in 1 area it may be advisable to select 2 or even 3 areas within easy working 

 distance of an experimental forest headquarters. 



Each experimental forest should, wherever possible in the interest of great- 

 est representation of conditions for scientific work, include in addition to the 

 area already specified a natural area of the character provided for below. 



OTHER CONSIDERATIONS 



The selection of experimental forests should be carried forward rapidly 

 enough so that the value for research of the most suitable areas will not be 

 seriously reduced, or destroyed for many years, by timber cutting. It will be 

 far better to select, designate, and hold such forests over a long period, of 

 years without any work in them than to lose them altogether for research or 

 to have their value greatly impaired. While the investigative work of the 

 Forest Service is being built up as rapidly as funds and competent men can 

 be obtained, it will probably be a good many years before the resources will 

 be large enough to carry out a large-scale program on the number of experi- 

 mental forests for each region indicated. Immediate or even future returns 

 to the Treasury in the cutting of timber for profit is not a valid, reason for 

 excluding from experimental forests areas needed for that purpose. The use of 

 such areas for research should establish a sound scientific basis for future 

 national-forest practice and that on private lands, and hence greatly ' increase 

 the returns on all forest lands. Similarly, sustained yield should be incidental. 

 The primary purpose in the handling of experimental forests should be to 

 install and maintain the series of investigative projects which seem most 

 necessary as a foundation for good silviculture, etc. 



Where suitable areas for experimental forests cannot be found on existing 

 national forests, consideration should be given to the acquisition of suitable 

 areas by gift under the provisions of section 5 of the act of March 3, 1925 (43 

 Stat. 1132 ) , by exchange, or, as a last resort, by purchase. 





