RESEARCH SUMMARY 



THE AUTHOR 



Individuals of a family test of ponderosa pine were scored 

 for the annount of dannage caused by infestation by gouty 

 pitch midge. The percentage of dead or dying tips varied 

 from to 57 percent for individuals and from to 20 percent 

 for families. Heritability based on individuals was 0.48 and 

 for families 0.60. Selection for resistance could yield a family 

 gain of 1 percent and an individual gain of 8 percent for 

 each unit of /. Use of these data in tree improvement 

 programs is discussed. 



R. J. HOFF is principal plant geneticist with the Station's 

 Genetics and Pest Resistance research work unit located in 

 Moscow, ID. He received a B.A. in biology (1957) from 

 Western Washington State University and a Ph.D. in botany 

 (1968) from Washington State University. He has been 

 working on the development of western white pine resistant 

 to blister rust since 1964. He also investigates resistance to 

 other pests in white pine and other conifers. 



February 1988 



Intermountain Research Station 

 324 25th Street 

 Ogden, UT 84041 



