began with methods of identification and description. In 1964-65, the work pro- 

 gressed to study of the effects of frost on internal wood structure and the peculiar 

 formations of annual rings affected by temperature excesses. This was followed by 

 studies of differences between Ontario tree species for resistance. Research in this 

 branch of tree physiology requires equipment construction and modification with 

 adjustment to a fine degree of accuracy. 



The effects of frost have been found similar in some respects to effects of 

 drought and this year study has begun of the structure and growth differences 

 caused by these factors on several native species. 



FOREST FERTILIZATION 



The application of various kinds and amounts of fertilizer to plantations is 

 under test. Encouraging results are being obtained and increases in growth of up 

 to 27 per cent is indicated in one test lasting five years. 



Wood Quality 



The purpose of the wood quality studies is to obtain an understanding of the 

 specific physical and chemical characteristics which provide the basis for the pre- 

 ference of forest industry for certain wood species. High yields of uniform quality 

 at low cost is the timber production goal. 



In 1962 a Wood Quality Unit was established in the Research Branch and the 

 Ontario Research Foundation receives an annual grant from the Department for 

 making pulping and other tests of wood samples provided them. 



During the 1965-66 year, a better understanding was gained of the variation 

 in structure of the wood of black spruce as it affects paper quality. Further emphasis 

 was given to the assessment of wood density in individual trees. Having obtained 

 an indication of total bole density by the measurement of 20% of the total bole 

 volume, an estimate of mean bole density was investigated from diameter core 

 samples, and gave encouraging results. 



Vertification of the preliminary estimates was planned for 1966 in which 

 groups of 20 trees would be destructively sampled with one disc being taken from 

 each 10% height level. The four major lowland site classes will be sampled in 

 Cochrane District and two or more upland site classes sampled in Geraldton 

 District. Measurements from this larger group of trees would permit suitable 

 regression analysis for an estimation to be made of the density of a standing tree 

 from one or more core samples taken from the lower bole. 



A power borer was designed and constructed by the Mechanical Section to 

 obtain a 3 A inch diameter core from trees up to 12 inches in diameter. This machine 

 penetrates and cuts cores at the rate of one inch per minute, and can be used at 

 any level on the tree bole. In addition to the calculation of tree density from core 

 samples, it should be possible to develop estimates of the anatomical properties 

 and pulping capability of standing trees. The Ontario Research Foundation has 

 completed a test to validate the use of small chips (lcmxlcmx'/s in.) in pulping. 



The Ontario Research Foundation has also completed a series of tests com- 

 paring plantation grown black spruce and slower grown trees from natural forests. 

 Their results indicate a marked superiority in paper strength (burst and tear) from 

 outerwood or older wood compared to corewood or younger wood of the trees. 

 An hypothesis was developed that differences in paper strength properties from 

 black spruce were associated mainly with fibre length rather than percent latewood 

 or specific gravity. 



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