Silvicultural Research Units 



Silvicultural research units have been established in administrative regions of 

 the province to study characteristics of commercial tree species which affect growth 

 and reproduction. The object is to develop economical cultural practices which will 

 ensure maximum production of quality wood. Such knowledge is essential to the 

 proper management of Ontario's forest resources. An outline of the work of the 

 main projects for each regional unit follows. 



MID-WESTERN FOREST RESEARCH UNIT 



In 1964, the regular programme of studies on the silvicultural characteristics 

 of the main tree species of the region was continued although, as in 1963, the col- 

 lection of new information through field work was minimized due to a reorganiz- 

 ation of the programme. Field examinations were carried out on two high priority 

 studies but the main emphasis for the year was placed on reducing the backlog of 

 compilations, analyses and reporting necessary to finalize certain of the long term 

 studies. 



The research co-ordination programme was inactive although provision of 

 forest library services was continued. No annual summary was published and there 

 was no annual meeting. 



Natural Regeneration, Growth Studies and Silvicultral Treatments (White 

 Spruce-Balsam Fir): In 1960, a modified cutting system, which combined soil 

 disturbance with the leaving of seed trees was established, to increase the white 

 spruce regeneration over that which normally results from mechanical logging in the 

 mixed-wood cover type. This year, the 50 residual stand study plots and the 1,000 

 regeneration quadrats on the 50-acre treatment area were re-examined. 



The results confirm the findings from similar earlier trials and indicate that 

 this combination of treatment can substantially increase white spruce, as well as 

 other species for which there is parent stock. However, the degree of success is very 

 dependent on the amount and type of ground disturbance. In this trial, mechanical 

 logging in tree lengths provided inadequate coverage of the treated areas. 



Growth studies and the effects of increasing competition will be continued. 



Trembling Aspen. Trembling aspen regeneration occurs profusely on a wide 

 range of cut-over conditions, particularly those harvested using mechanical equip- 

 ment. In 1959, a major study was initiated to determine if the existing and future 

 quality of the young stems could be forecast by some characteristic(s) in their 

 physical appearance. Simple analysis techniques on the detailed descriptive infor- 

 mation gathered on each of the aspen stems occurring on 840 mil-acre quadrats, 

 failed to reveal any significant or useable relationships. In 1964, the 5,500 stems 

 were re-examined and re-described as a preliminary step to an analysis by computer 

 programming. Multiple regression and correlation analyses will be conducted on 

 such features as present internal quality, age, years since cutting, original cover type, 

 site type, present stand density, branching habits, foliage characteristics, presence 

 of black spots and fungal fruiting bodies, bark colour, form, vigour and general 

 appearance. This analysis is as yet incomplete. 



CENTRAL FOREST RESEARCH UNIT 



The work of this unit consists of field and laboratory studies of problems of 

 tree nutrition, particularly spruce, and studies of the productivity ecology and racial 

 variation of red spruce. It also includes studies of tree nutrition in relation to forest 

 disturbance. Work on smelter fume pollution in relation to forest soils and vege- 



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