to focus on loblolly pine. 

 Regionwide tests have shown that 

 fertilization at planting, particularly 

 on wetter sites, increases growth 

 and yield by 30 to 40 percent over 

 a 15- to 20-year period; returns on 

 investment range from 10 percent 

 to 15 percent. Such fertilization on 

 many wetter sites often makes the 

 difference between survival and no 

 survival and thus, in effect, has 

 added area to the commercial pine 

 production base. 



"Catchup'* or midrotation 

 fertilization effects were found to 

 last for 5 to 8 years with similar 

 growth and yield response. Returns 

 on investment ranged up to 20 

 percent for companies growing 

 trees for a combination of several 

 products. 



Slightly over 1 million acres 

 (404,700 ha) had been fertilized up 

 to 1981 in the southeastern Coastal 

 Plain (Stone 1983; Cooperative 

 Research in Forest Fertilization 

 1983; Allen, personal 

 communication). 



Plantation Growth and Yield and 

 Management — There are four 

 cooperatives working in this area — 

 at Georgia, VPI and SU, 

 Mississippi State, and, most 

 recently, Stephen F. Austin. All 

 four programs have involved large- 

 scale, permanent field plot systems 

 to determine growth and yield of 

 planted loblolly pine, or loblolly 

 and slash pines, on site-prepared 

 lands under varying intensities of 



site preparation in combination 

 with other cultural practices. 



The first of these was established 

 in 1976 at the University of 

 Georgia under landership of 

 Jerome Clutter, who was the 

 cornerstone for what was generally 

 recognized as a center of 

 excellence in forest biometry. His 

 graduate students have gone out to 

 establish effective programs 

 elsewhere. One such program is at 

 VPI and SU, where Harold 

 Burkhart leads a cooperative that 

 has developed a model for 

 determining the impact of 

 hardwood competition on pine 

 plantation yield and profitability. 

 Burkhart" s team found that a 

 10-percent reduction of crown 

 competition within lower ranges of 

 such competition added $150 to 

 $160 per acre ($371 to $395 per ha) 

 to the net present worth of such 

 plantations based on forest 

 industry cooperators' figures. 

 Some 100,000 acres (40,470 ha) per 

 year are now being treated by 

 cooperators with plantation value 

 increases totaling some $15 million 

 annually (Bailey and Burkhart, 

 personal communications; 

 Burkhart and Sprinz 1985). 



Insect and Disease Protection — In 

 Texas, Stephen F. Austin State 

 University and Texas A. & M. 

 forest entomologists, in 

 cooperation with the USDA's 

 Expanded Southern Pine Beetle 

 RD&A Program, developed a 

 system for hazard rating of East 



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