on herbs and grasses in a fire guard were evaluated one year after treatment. Telvar, 

 Urox and Simazine gave excellent results. The soil sterilants, Dybar and Urab also 

 gave encouraging results by eliminating weed trees and shrubs in a stand conversion 

 study at the East Gwillimbury Research area. Thinning with chemicals was con- 

 tinued in a silver maple swamp and assessment made of the effects of from one to 

 three applications, applied once, twice and three times in the same year, and at 

 yearly intervals over a three year period. 



SOUTH EASTERN FOREST RESEARCH UNIT 



The main objectives of the South Eastern Research Unit are (1) to study 

 the effects of prescribed burning and its role in forest management in Ontario. (2) 

 To study the silvics of basswood with emphasis on the problems of germination. 

 (3) To study the artificial regeneration of conifers on shallow till soils. 



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

 origin the third spring burn and the second fall bum were carried out successfully. 

 Research Branch personnel also supervised two large bums in a 5-acre hard maple 

 stand and a 10-acre yellow birch stand. 



In the Swan Lake Research Reserve, the last of five scheduled fall burns was 

 carried out in a stand which was predominantly hard maple. This species sometimes 

 requires a few years to react to treatment. However, the mortality of trees greater 

 than 4.5 inches d.b.h. now seems to be negligible. 



Basswood. In September and October 1962 four seed collections were made 

 at different stages of development. This seed was stratified in a storage pit over 

 winter. When the seeds were uncovered in the spring of 1963, most had well 

 developed radicles. Germination of the four collections ranged from 37 per cent 

 to 79 per cent, the best germination occurring in seeds collected when the seed coat 

 was soft but the seed fully mature. 



Basswood seedlings were underplanted in 1962 and 1963 in a hardwood 

 cutover and the survival is 77 per cent and 90 per cent respectively. Permanent 

 sample plots were established in the cutover, and natural basswood seedlings on 

 the plots were staked and tagged for studies of growth and survival. These data 

 will be compared with growth records of natural hard maple seedlings. 



White spruce. In this co-operative program with the Wildlife Section and the 

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

 timber, further regeneration studies were made prior to the final cut on the study 

 area in the winter of 1963-64. 



Artificial Regeneration. After four growing seasons a tally of the growth and 

 survival of white pine, red pine and white spmce on shallow till over bedrock 

 indicated over 80 per cent survival for fall planted white and red pine of 2-2 age 

 and spring-planted red pine of 2-0 and 2-2 age. The survival of white spruce ranged 

 from 14 per cent to 65 per cent. 



Nursery and Plantation Research 



The program of reforestation research is designed to contribute to the scientific 

 advancement in the field of artificial regeneration in the Province. The studies are 

 conducted in nurseries or in planting areas. 



FERTILIZATION STUDIES 



Fertilizers are being tested to obtain higher survival and better growth of newly 

 established plantations. Experimental fertilization has been done also in several 



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