CONTENTS 



Page 



INTRODUCTION 1 



LITERATURE REVIEW ' 2 



MATERIALS AND METHODS 5 



RESULTS 7 



Survival of Sj Trees 7 



Comparative Delay and Extent of Fruiting of S j Trees .... 7 

 Crossing Success as Measured by Production of 



Mature Female Cones and Filled Seeds on Sj's 10 



DISCUSSION AND CONCLUSIONS 12 



SUMMARY 16 



LITERATURE CITED . . . 17 



ABSTRACT 



Pinus monticola Sj seedling mortality, timing and extent of 

 fruitir^, strobilus attrition, crossing success, seed yield, and 

 seed weight are compared for 18 Sj lines and their outcrossed 

 half-sib lines. No reproductive barriers are restrictive enough 

 to preclude continued inbreeding. Filled seed yields from 

 second generation inbreeding are low but consistent and large 

 enough to justify continuing an experimental program. Results 

 of experimental single crossing between Sj lines should guide 

 decision on a practical inbreeding program. 



