Table 7 .--Theoretical 45-month development of cones, seeds, and 



seedlings from ovulate bud formation to the second year 

 of seedling growth under normal conditions , compared 

 with development using recommended management conditions 



Stage of 

 development 



Potential seedlings 



Number 



Percent 



NORMAL CONDITIONS 



Ovulate buds (1,000) 



^ 80, 000 



100. 



.00 



First-year survival of conelets (270) 



21,600 



27. 



,00 



Second-year survival of cones (60) 



4,800 



6. 



,00 



Filled seeds after seedfall (75% of above) 



3,600 



4. 



,50 



Overwintering survival of seed 









(12% of above) 



432 



0. 



.54 



Surviving seedlings at beginning of second 

 growing season (50% of above) 



^216 







.27 



RECOMMENDED MANAGEMENT CONDITIONS 



Ovulate buds (1,000) 



80,000 



100, 



,00 



First-year survival of conelets (290) 



23,200 



29, 



,00 



Second-year survival of cones (200) 



16,000 



20, 



.00 



Filled seeds after seedfall (75% of above) 



12,000 



15. 



,00 



Overwintering survival of seed 









(50% of above) 



6,000 



7, 



.50 



Surviving seedlings at beginning of 









second growing season (50% of above) 



3,000 



3, 



,75 



^ased on 80 seeds per cone 

 Idaho [James D. Curtis and Marvin 

 pine in the Northern Rocky Mount 

 Forest and Range Experiment Stat 



2 Based on 50 percent surviv 

 1949 to May 1950 in western Mont 

 of the favorable growing conditi 

 about 20 percent survival which 

 and Curtis 1965b) and from 1934 

 (Fowells and Stark 1965). This 

 to 86 seedlings or 0.11 percent 



in mature, scattered stands in central 

 W. Foiles. Regeneration of ponderosa 

 ains . USDA Forest Serv., Intermountain 

 ion, Ogden, Utah. (In preparation).] 

 al recorded for ponderosa pine from June 

 ana. This figure is probably high because 

 ons that year. A closer estimate would be 

 occurred in 1959 in central Idaho (Foiles 

 to 1941 in the Sierra Nevada of California 

 would decrease the theoretical survival 

 of the potential . 



15 



