that p = .95; trends = one or more tests appear to support conclusions, but because 

 of time limits, confounding variables, or design limitations, no statistical signifi- 

 cance was obtained; observed = no measurements were made but the relationship seemed 

 apparent during field observations. The latter two classes should be accepted cau- 

 tiously until proper testing or extensive experience validates them. The conclusions 

 are as follows: 



1. Seedling survival and height growth is positively correlated with soil 

 depth (Tests I, III, V: trends). 



2. Animal damage is extensive (up to 82 percent) and affects both survival and 

 height attainment (I, III to V: trends). 



3. Hand scalping with an application of simazine provided the least 

 expensive control of competition in a moist summer--1964 (IV: trends). 



4. Northwest aspects have better survival (IV: *; III: trends), but fifth- 

 year heights are greater on warmer southeast aspects (III, IV: trends). 



5. Treatments have less influence on survival in the more moist seasons and 

 sites (III to V: trends). 



6. Native grass competition (moderate density levels) seem less severe on 

 seedling survival than brush species in this h.t. (Ill, IV: observed). 



7. Animal damage did not appear to be influenced by mulch materials 

 (I, III to V: trends). 



8. Mean fifth-year heights for undamaged seedlings ranged from 0.86 to 

 2.50 feet. Heights appeared to be positively correlated with survival, 

 soil depth, and relative temperatures (I, III to V: trends), 



9. Five-year heights were greater when black polyethylene was used (III to 

 V: trends). 



10. On granitic soils in central Idaho the surface 12 inches of soil reaches 

 the "wilting point" (15 atmospheres determination) during the summer 

 unless additional moisture comes from summer storms (V: trends). 



Recommendations 



As a result of these studies, the following two recommendations seem 

 appropriate. 



1. Initial seedling stocking standards should take into account the onsite 

 differences and be adjusted as to the planting area to insure adequate 

 stocking at some target date after planting, for example, 3, 4, or 5 years. 

 The survival rates vary greatly with the onsite environment, i.e., specific 

 cover species, aspect, soil depth, animal populations, and summer precipi- 

 tation. The probabilities of abnormal summer precipitation levels should 

 be used to weight the initial standard. Sites similar to those in these 

 studies may require planting 600 seedlings, or more, to have 300 live 

 seedlings after 3 years. 



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