compatible with use of fire 

 and machines to control 

 competing vegetation. 

 Comprehensive guides for 

 such management have 

 been issued by the Georgia 

 Forest Research Council 

 (Wahlenberg 1965) and by 

 Langdon and Bennett 

 (1976), among others. 

 Research has also shown 

 that for landowners wishing 

 to retain a natural forest, or 

 avoid the costs of site 

 preparation and planting, 

 forests can be managed on 

 a selection system. The 

 shelterwood system also 

 has proved to be a low-cost 

 and reliable system in the 

 case of longleaf and short- 

 leaf pine (e.g., Lawson 

 1979). 



In essentially all pine man- 

 agement programs, control 

 of hardwoods and other 

 undesirable vegetation is 

 essential for satisfactory 

 regeneration, survival, and 

 growth of the preferred 

 pines. This fact is, of course, 

 a major argument for pre- 

 scribed burning. Early 

 studies indicated that hard- 

 woods could also be con- 

 trolled by injecting unwant- 

 ed trees with chemicals 

 such as sodium arsenate. 

 Subsequently, sprays of 



2,4,5-T, picloram, and 

 glyphosate were found to 

 be effective (e.g., Peevy 

 1976). More recent studies 

 showed promise for forestry 

 applications of newer herbi- 

 cides (Mann and Hayes 

 1978). Also worthy of note 

 is a lengthy Agriculture 

 Handbook called "Pesticide 

 Background Statements," 

 prepared by the Mitre 

 Corporation (USDA Forest 

 Service 1 984b). The detailed 

 data contained therein are 

 essential in the preparation 

 of environmental impact 

 statements for projects 

 involving the application of 

 herbicides. 



Use of herbicides has saved 

 landowners millions of 

 dollars in site preparation 

 and timber-stand improve- 

 ment and greatly increased 

 growth of the more valuable 

 pines. Intensified concern 

 over environmental impacts 

 from use of herbicides, 

 however, and regulatory 

 restrictions make future use 

 of such chemical controls 

 somewhat uncertain and 

 suggest the need for contin- 

 uing improvements in tech- 

 nology. 



Research in use of fertilizers 

 has demonstrated that 



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