are designed to measure its productivity on different sites in pure and mixed 

 stands across its range. 



It is hoped to provide explanations of differences in spruce growth in terms 

 of nutrient uptake from the soil. Work is also proceeding in the examination 

 of different strains for the best ecological characteristics. A large scale experi- 

 mental underplanting has been established which should provide information 

 useful in silvicultural practice and of a fundamental nature on shade tolerance. 



Smelter Fume Pollution 



To provide information and explanations on the nature of smelter fume 

 damage and its effects on forest vegetation, forest soils and waters as a prerequisite 

 for suggesting means of pollution control and the best means of forest land 

 management under the circumstances. 



In the vicinity of Sudbury, Cutler and Wawa, large areas of forest have 

 been removed from forest productivity due to effects of smelter fumes. The 

 research officer and a member of the Botany Department, University of Toronto, 

 have carried out studies at both Sudbury and Wawa on the fallout from the 

 smelter fumes and the effects on forest soil, lake waters, aquatic and forest 

 vegetation. Two papers have been published, and two more will follow. 



South-Central Region 



Sugar Maple Growth and Quality Studies 



The abjective of this work is to obtain information that will provide a 

 sound basis for managing sugar maple stands in the Region. It is believed that 

 the maintenance of a hardwood industry will be dependent upon our ability to 

 produce good quality material, and that the large areas of sugar maple which 

 form the majority of hardwood growing stock will require judicious cultural 

 treatment if they are to serve the prospective need. To this end, studies are being 

 conducted to show how defect is associated with growth or growing conditions, 

 and to define the conditions under which suitable growth and quality of sugar 

 maple can be attained. 



A multiple regression and correlation program is being finalized for analysis, 

 using an electronic computer on data taken from several hundred samples in the 

 field. 



A system of grading the standing tree for quality has been developed, and 

 in conjunction with studies of stem analysis, mill recovery and growth by means 

 of permanently installed diameter tapes, a working knowledge has been developed 

 of the growth characteristics of the species. This work is supplying supporting 

 evidence to the developing art of maple management. 



Tubed Seedlings 



The objective of this work is to develop an acceptable and inexpensive 

 method of reforestation which could be useful in extending the planting season 

 and in providing stock for planting immediately after wildfires, and on short 

 notice. 



Studies in the past year were directed towards showing the influence of 

 tubed material and size upon the development of seedling stock. In addition, 

 two soil media were also tested for the same purpose. 



White and Red Pine — Regeneration and Growth Studies 



This work is designed to evaluate various techniques for estabhshing and 



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