White Pine Blister Rust 



Reconnaissance surveys and associated research are conducted annually by 

 the Research Branch, in co-operation with the Forest Protection Branch and the 

 Forest Districts which are within the range of white pine in Ontario. The current 

 programme includes: 



1. The blister rust reconnaissance programme designed to document and 

 elucidate blister rust epidemic in Ontario. 



2. Investigation of the effects of fire on the development of blister rust in 

 the forest, specifically for the purpose of accommodating white pine 

 planting to best advantage. 



3. Evaluation of risk and damage accrual to facilitate current choice of 

 silvicultural and management alternatives, e.g. selection of species, 

 protection, salvage, etc. 



In 1965, work was done in the Parry Sound, Sudbury and Sault Ste. Marie 

 Districts. A manuscript of a report was completed on examinations and re- 

 examinations in various localities in these districts, including tables showing 

 incidence of infection in mature natural forests and young planted stands. 



Mensuration, Statistics, and Economics 



The work of three Units is integrated to provide a service which assures 

 dependability of results and uses time of staff efficiently. 



FOREST MENSURATION 



Yield from Forest Land. Records of red pine growth, mortality and thinnings, 

 taken from permanent sample plots in County Forests, were analyzed. Total 

 volumes and periodic increments were determined to establish rates of growth and 

 patterns of stand development in plantations thinned to prescribed densities. This 

 key information was used on an ARDA-sponsored study of forest productivity 

 carried out by University of Toronto and Research Branch staff. 



Preliminary steps were outlined for the continuous maintenance of permanent 

 sample plots, including methodical storage and analysis of data obtained from them. 



Data from which British yield tables were made were organized for further 

 study of the multiple relationships between factors influencing plantation yields. 



Construction of Volume Tables. A computer programme for the preparation 

 of standard volume tables, made two years ago in conjunction with the University 

 of Toronto, was expanded to work out volumes according to eight log rules or 

 scaling methods. It was modified to handle measurement data from 23,000 sample 

 trees of all available species. Some 75 tables were produced for the northern 

 Ontario pulp species such as spruce, jack pine and poplar, using a variety of 

 merchantable limits and age or regional groupings. 



Volumes interpolated from the standard tables were used in estimating the 

 quantity of timber to be cut on several commercial operations. 



MATHEMATICAL STATISTICS 



Services to Timber Sales (Timber Branch). A system has been developed for 

 computing the net merchantable volumes in cubic feet obtained by licensees on 

 operations involving tree-length logging and variable-length slashing for sawmills. 

 This system was designed to give accurate estimates of total net-merchantable 



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