GENOTYPES SELECTED 



Figure 2 .- -Approximate relationship between per- 

 cent gain in 16-year height and number of geno- 

 types selected for seed orchards at each plant- 

 ing site. The number of genotypes was derived 

 from the various combinations of family and 

 individual tree selection detailed in figure 1. 



PUBLICATIONS CITED 



Namkoong, G. 



1966. Inbreeding effects on estimation of additive genetic variance. For. Sci. 12:8-13. 

 Namkoong, G. 



1979. Introduction to quantitative genetics in forestry. USDA For. Serv. Tech. Bull. 1588, 

 342 p. 



Namkoong, G. , and M. T. Conkle. 



1976. Time trends in genetic control of height growth in ponderosa pine. For. Sci. 22:2-12. 

 Namkoong, G., E. B. Snyder, and R. W. Stonecypher. 



1966. Heritability and gain concepts for evaluating breeding systems such as seedling 

 orchards. Silvae Genet. 15:76-84. 



Rehfeldt, G. E. 



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Steele, R. G. D. , and J. H. Torrie. 



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 Wang, C. W. 



1967. The genetic improvement of ponderosa pine in Idaho. Univ. Idaho, For., Wildlife and 

 Range Exp. Stn. Note 7, 7 p. Moscow. 



Wang, C. W., and R. K. Patee. 



1974. Variation in seed characteristics and seedling growth of open pollinated ponderosa 

 pine progenies. Univ. Idaho, For., Wildlife and Range Exp. Stn., Pap. 15, 11 p. Moscow. 

 Wang, C. W., and R. K. Patee. 



1976. Regional variation in ponderosa pine, the 5-year result. Univ. Idaho, For., Wildlife 

 and Range Exp. Stn., Bull. 10, 7 p. Moscow. 



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