Silvicultural Research Units 



Silvicultural research units have been established in the different administrative 

 regions of the province to study those characteristics of the commercial tree species 

 which affect growth and reproduction. The object is to develop cultural practices 

 which will ensure maximum production of quality wood within economic limits. 

 Such knowledge is essential for the proper management of the forest resource of 

 Ontario. An outline of the status of the main projects for each regional unit is 

 given below. 



MID-WESTERN FOREST RESEARCH UNIT 



During 1962, the program of studies on the silvicultural characteristics of the 

 commercially important tree species of the area was continued. White spruce, 

 balsam fir, black spruce and jack pine are the most important species for study in 

 this region. 



Natural Regeneration. In the white spruce - balsam fir forest type, 3200 

 mil-acre quadrats have been established to compare the regeneration obtained 

 following the conventional cutting of all merchantable trees on an area, with that 

 obtained when some white spruce were left to provide a seed source. An improved 

 seedbed was obtained by disturbing the ground surface in two ways, by mechanical 

 scarification and by the use of tree-length logging. Preliminary results have shown 

 an improvement in the numbers of white spruce seedlings when seed trees were 

 present; however, severe competition has developed from underbrush and other 

 tree species. 



The assessment of regeneration in black spruce - jack pine stands following 

 conventional clear-cutting, was carried out on 1060 mil-acre quadrats established 

 in 1949 in the Auden area. This study of regeneration, stand composition changes 

 and growth will be continued. 



NORTHERN FOREST RESEARCH UNIT 



The study of the silvics of the important trees in the black spruce cover type 

 was continued. The satisfactory development of black spruce growing on lowland 

 sites is the main objective in this unit. 



Natural Regeneration. An experiment to improve the growth of spruce 

 regeneration on deep peat soils, by lowering the water table with drainage ditches, 

 was established in 1960 on the Leitch township research reserve. Weekly measure- 

 ments of water table levels were taken throughout the growing season. Ditches 

 that were made two years previously had become partially filled by peat; these 

 were re-opened, in part by manual labour and in part by dynamiting. Additional 

 strips were cleared of trees for later dynamiting of drainage ditches. This project 

 has indicated that the lateral flow of water into the drainage ditches has been slight. 



The literature from Russia and the Scandinavian countries, which have similar 

 peat problems, has been followed closely to assess their methods of dealing with 

 peat. 



An experimental cutting was carried out during 1951 in a black spruce stand 

 in Leitch township to determine the effect of different cutting methods on 

 regeneration. This study is continuing. 



CENTRAL FOREST RESEARCH UNIT 



The work of this research unit consists both of field and laboratory studies 

 of problems of tree nutrition related particularly to forest disturbance and 



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