Explorations carried out into the rooting systems of several mature trees 

 indicated that a similar sphagnum problem existed. As yet, not enough data has 

 been collected. However, it seems sphagnum growth is killing off the rooting 

 system of spruce on lowland sites. The poor growth of the spruce may result 

 from the trees having to establish a new and higher rooting system to obtain the 

 nutrients needed. 



A study of sphagnum control has been approved and will be initiated this 

 year. Experimental work to illustrate the role of different nutrients in the life of 

 black spruce starts this spring, on stock planted last fall. Mass observations made 

 last year have led to the establishment of carefully controlled experiments in group 

 planting to see if, by this means, some of the cut-overs which have failed to 

 regenerate can be successfully rehabilitated. 



If these methods or their possible successors work, we can look not only to 

 the maintenance of our present commercial stands, but to the expansion into fertile 

 areas which now support a sub-commercial forest. 



In the preparation of this work, a great deal of attention has been paid to 

 studies of a similar nature being conducted in other countries of the northern 

 hemisphere. Translations of botanical and forestry articles have been made from 

 Russian, Finnish and Norwegian; three have been published as Information 

 Papers. Articles by 50 authorities on organic sites have been reviewed, and the 

 results of their work as applicable to Northern Ontario have been published as 

 a Section Report. Another submission for a Section Report dealing with Ontario 

 conditions, is ready for publication. 



SOUTH CENTRAL FOREST RESEARCH UNIT 



The objective of this unit is to provide information for the management of 

 the important commercial tree species that occur in South-Central Ontario; sugar 

 maple, yellow birch, white and red pine. Work is being done on the problems of 

 regeneration, growth and quality of these species. 



Sugar Maple Growth and Quality. The developing shortage of high quality 

 hardwood timber following extensive exploitation of yellow birch, has prompted 

 the present programme of research on sugar maple growth and quality. The pre- 

 ponderance of this species in the hardwood forests of the region suggests that 

 continuing supplies of hardwood in the next rotation must come from existing 

 sugar maple stands. 



In 1959 a study of factors that affect the production of high quality maple 

 was commenced. This work was first carried out on small saplings, and more 

 recent investigations include larger saplings, poles and sawlog sizes. 



To date, the observations substantiate the concept of the relationship between 

 growth (rapid and continuous) and quality wood production. The current work 

 includes a study of trees wounded artificially. 



A marking scheme, giving emphasis to stand improvement, maintenance of 

 balanced stand structure and ease of application, is being tested with promising 

 results. 



Red and White Pine and White Spruce. The Ottawa Valley lumber industry 

 is keyed to softwood production, mainly white and red pine. Because of this high 

 preferential demand, a study of stand conversion from low grade hardwoods to 

 pine was initiated in the Petawawa Management Unit in 1954. The performance 

 of red pine, white pine and white spruce planted stock is being studied on three 

 represenative sites and under four periods of suppression from hardwoods prior to 

 a release. The work to date, indicates a marked difference in survival and growth 

 between species, site and suppression period. 



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