and at yearly intervals for a period of three years was assessed. Results indicate 

 that one heavy application or three medium applications in one growing season 

 are almost 100% effective in eradicating the unwanted stems. Maximum kill takes 

 up to two years after treatment. 



Chemical Shrub Control. Chemical control of grassess and herbs two years 

 after treatment in a fire-guard indicated that Urox, mixture of Radapon and 2,4-D 

 amine, Telvar and Hyvar were still effective in controlling plant growth. 



Asexual Reproduction of Silver Maple. The asexual reproduction studies of 

 20 high-quality silver maple phenotypes for lumber production were continued at 

 Orono nursery. Most of the trees have now been successfully budded and will be 

 layered in the summer of 1965. In addition, one high sugar producing silver 

 maple was also budded at Orono nursery. 



Growth Studies. Seasonal growth studies using dendrometer bands on silver 

 maple, hard maple, American basswood, white ash and red pine were continued. 

 The project is designed to correlate the growth of the aforementioned tree species 

 with thinning, spacing, temperature, moisture and other site factors. In addition, 

 five-year measurements were made in a second growth hardwood plot near Wood- 

 stock for the purpose of studying stand development. 



SOUTH EASTERN FOREST RESEARCH UNIT 



The three main objectives of the South Eastern Research Unit are: 



To determine the effects of prescribed burning and its role in forest 



management in Ontario. 

 To learn the silvics of basswood, with emphasis on problems of 



germination. 

 To assess the regeneration of white spruce in swamps being managed 

 for both deer and timber. 



Prescribed Burning. In a small diameter hardwood stand, mainly of sprout 

 origin, the fourth spring burn and the third fall burn were carried out successfully. 

 The fourth series of fall burns took place in a mature hardwood stand in another 

 study area. 



In the Swan Lake Research Reserve in 1963, the last of five scheduled fall 

 burns was carried out in a stand of predominately hard maple. Even though this 

 species sometimes requires a few years to react to treatment, observations to date 

 indicate the morality of trees greater than 4.5 inches d.b.h. is negligible. 



Basswood. Basswood seed studies with respect to fruit collection, storage 

 and germination were completed in 1964. The first results are compiled in a 

 Research Report entitled "Germination of early collected fruit of Tilia 

 americana L." 



An Interdepartmental Co-operative Research Basswood Planting Project was 

 started in 1964 to investigate the feasibility of planting basswood on tolerant hard- 

 wood clear-cut strips. Basswood seedlings were planted on northern and southern 

 slopes, where survival was 90% after the first year. Additional plantings will be 

 carried out in 1965 and 1966. Natural regeneration of basswood is being studied 

 on these strips. Seedlings on mil-acre quadrat plots are marked, and their develop- 

 ment recorded annually. 



White Spruce. In this co-operative programme with the Wildlife Section and 

 the Tweed Forest District, designed to study the management of an area for deer 

 and timber, the final cut took place and analysis of the regeneration data is 

 continuing. 



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