APPLICATIONS 



The results to date indicate that only two seed zones are necessary for western 

 white pine in north Idaho, and probably for the adjacent white pine areas in north- 

 eastern Washington and northwestern Montana as well. The main, or low, zone would 

 include all the area below 1,375 m, with the exception of the most severe sites where 

 the upper boundary might be lowered to 1,250 m. The second, or high, zone would include 

 all the area above 1,375 m and a limited area related to severe sites between 1,250 m 

 and 1 , 375 m. 



Two seed orchards, with selections related to the above seed zones, should be suf- 

 ficient for the next phase of the blister rust resistance breeding program. Siblings, 

 or vegetative propagules, of seedlings intended for either orchard should be tested at 

 several sites to facilitate selection of those individuals or families that are both 

 broadly adapted and fast growing. 



Seed from the present low- and mid-elevation orchards can be combined and used on 

 low- and mid-elevation sites throughout north Idaho. It can probdbly be used at eleva- 

 tions up to 1,375 m on most sites. Seed from the high orchard should be used for sites 

 above 1,375 m. This is a conservative approach, as our results so far show little or 

 no difference in survival or growth among seedlings of low-, mid-, or high-elevation 

 origin at the high sites. However, long-term effects have shown up in other species. 



PUBLICATIONS CITED 



Barnes, B. V. 



1967. Phenot>'pic variation associated with elevation in western white pine. For. Sci. 

 13(4) :357-364. 

 Callaham, R. Z. , and A. R. Liddicoet. 



1961. Altitudinal variation at 20 years in ponderosa and Jeffrey pines. J. For. 

 59(11) : 814-820. 

 Conkle, M. T. 



1973. Growth data for 29 years from the California elevational transect study of 

 ponderosa pine. For. Sci. 19(l):31-39. 



Rehfeldt, G. E. 



1974. Genetic variation of Douglas-fir in the Northern Rocky Mountains. USDA For. 

 Serv. Res. Note INT-184, 6 p. Intermt. For. and Range Exp. Stn., Ogden, Utah. 



Rehfeldt, G. E. 



[In press.] Ecotypic differentiation in populations of Finus montiaola in north 

 Idaho- -myth or reality? Am. Nat. 

 Rehfeldt, G. E., and R. .J. Steinhoff. 



1970. Height growth in western v\'hite pine progenies. USDA For. Serv. Res. Note 

 INT-123, 4 p. Intermt. For. and Range Exp. Stn., Ogden, Utah. 

 Squillace, A. E. , and R. T. Bingham. 



1954. Breeding for improved growth rate and timber quality in western white pine. 

 J. For. 52(9) :656-661. 

 Squillace, A. E., and R. T. Bingham. 



1958. Localized ecotypic variation in western white pine. For. Sci. 4(1): 20-34. 

 Townsend, A. M. , J. W. Hanover, and B. V. Barnes. 



1972. Altitudinal variation in photosynthesis, growth, and monoterpene composition of 

 western white pine [Pinus montiloola Dougl.) seedlings. Silvae Genet. 2] (3-4): 

 133-139. 



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