In one phase of this work, the seedling growth of black spruce originating 

 from specific stands was analysed to determine the genetic effects of ecotypes. 



Site Research 



Site research is the study of the productivity of land. Knowledge pertaining 

 to the relationships between soils, climates and crops is organized in a classification 

 system adaptable to various kinds of management of renewable natural resources 

 in Ontario. The forest is the major crop considered, but the classification system 

 also provides a biological basis for rating the potential of land for wildlife, agri- 

 culture and recreation. 



The research programme is divided into three parts: Regional Site Research, 

 Factorial Site Research and Land Productivity Research. 



REGIONAL SITE RESEARCH 



Regional Site Research is the study of the variations in the relationships 

 between soil, climate and forests from place to place, and evaluates the significance 

 of each combination of factors on crop production and management. 



In the year under review, the field work for establishing landscape units in 

 Northwestern Ontario west of the 86th meridian and south of the 50° 30' parallel 

 of latitude was completed this year. Volume 1 of Forest Sites of Site Regions 5S 

 and 4S was published and Volume 2 was prepared for publication by one of the 

 Site staff. Two maps of the surface geology of this area prepared by him were 

 published. The completion of reports for Region 3W and the establishment of 

 reference areas in this region will be postponed owing to his resignation in 

 September, 1965. 



Another Site researcher prepared two maps, showing the distribution of 

 parent geological materials in Northeastern Ontario between the 46th and 50 

 parallel of latitude. 



In southern Ontario the physiographic sites of the Algonquin Uplands were 

 mapped in greater detail than on a previous reconnaissance survey. 



FACTORIAL SITE RESEARCH 



Factorial Site Research is the study of individual site factors and their role 

 in the productivity of common sites in Ontario. Soil nutrients and soil moisture 

 are under investigation at present. 



As part of the overall programme concerned with moisture as a site factor 

 of major significance, work continued in the quantitative study of soil moisture 

 deficits, their amelioration through thinning and irrigation and their influence on 

 tree growth. This work was a continuation of the study started in a red pine 

 plantation in Essa township last year. Although this study has not been completed 

 yet, a preliminary analysis suggests that the irrigation was particularly effective 

 during the period of rapid diameter growth (late June-early July), but did not 

 prolong the period of diameter growth in the late summer. The final analysis of 

 data will be made after growth has been recorded for a third season. 



A new experiment, in co-operation with the Reforestation Unit, to determine 

 the influence of various levels of moisture supply on the growth of red pine, white 

 spruce and larch seedlings in nursery seedbeds was initiated in a growth chamber 

 during the winter. This experiment saw the use of a pressure bomb, built by the 



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