trees and the severity and duration of the frost. This work Is expected to Indi- 

 cate modifications of nursery operations, planting techniques, and times of 

 planting which will circumvent the bulk of the damage from frost. A technique in 

 which electrical resistance is used to measure the amount of the damage to plaiit 

 tissue has been extended to assist in research work in this problem. 



Size and Age-class of Planting Stock 

 The series of plantings, started in 1957, to compare the results of 

 planting smaller and younger stock (less expensive to produce in the nurseries) 

 with the accepted standard sizes and age-classes of each species was continued ^ 

 with a number of plantings in i960. The results of this work will be studied in 

 terms of the survival and growth over a several year period; no iinmediate general 

 conclusions are expected. 



REGIONAL FOREST RESEARCH 



Mid-We stern Region 



During 1960, the sllvicultural research was continued in the most 

 Important forest stands of north-western Ontario. A new trial of a modified 

 cutting system was established in a mixed-wood cover type to favour the species 

 white spruce. 



The research co-ordination program was continued and the Annual Project 

 Summary was published. This regional research office continued to co-operate in 

 supplying forestry library services. 

 Natural Regeneration, Growth Studies and Sllvicultural Treatments . 



White Spruce . A cutting system incorporating ground disturbance and 

 the leaving of seed trees was established to improve the white spruce regenera- 

 tion conditions which normally follow mechanical logging in the mixed-wood cover 

 type. With the active co-operation of the Marathon Corporation, studies were 



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