these species are genetically much more variable than red pine. The hybridization 

 was mainly within the Lariciones section. Interspecific pollinations were made on 

 1531 flowers of 36 clones, involving the species: P. resinosa, silvestris, nigra, mugo, 

 clensiflora, tabulaejormis, hwangshanensis and some interspecific hybrids of the 

 above. The cross P. pungens x banksiana was also attempted. A single red pine 

 bearing a genetic marker was pollinated with different mixtures of self and dead 

 pollen to determine if there was a selection against this marker. 



Six clones of P. mugo, two of P. silvestris, as well as seedling populations of 

 P. resinosa, silvestris and hwangshanensis were the main acquisitions. Scions from 

 six P. rigida and four P. rigida x echinata, and seeds from populations of P. rigida 

 x elliottii, P. rigida x echinata were also acquired. 



POPLAR 



The production of aspen-like hybrids, suitable for growing in southern Ontario 

 continued to be the chief aim of this project. 



The new acquisitions comprised 15 clones and four populations, mostly of 

 aspen materials. A total of 155 new clones were selected, mainly on the basis of 

 growth rate, growth form and freedom from disease. 



In the fall of 1961, a total of 7383 cuttings were set out for rooting ability 

 tests. Of these, 4920 were used in a more detailed analysis and represented 82 

 clones. Only four clones of P. alba in this test had a rooting ability of 65% or 

 over. Thus far no first-generation aspen hybrids have reached this level of rooting. 

 In the fall of 1962 a total of 9608 cuttings were set out for rooting ability tests 

 and of these, 2460 represented 41 clones for more detailed observations. Poplar 

 materials were supplied to establish four test plantations with a total of 3902 

 plants. 



WHITE CEDAR 



The production of improved types of this species and of western red cedar 

 hybrids, hardy in southern Ontario, is the aim of this project. 



The survival of some western red cedar populations set out in the Ganaraska 

 Forest in 1961 was tallied. Several populations contained a relatively high pro- 

 portion of plants which are winter hardy at this locality. A number of rooted 

 cuttings and hybrid seedlings were set out on their permanent location at the 

 Southern Research Station. 



SWEET CHESTNUT (Castanea) 



The aim of this project is the production of hardy dwarf types, resistant to 

 blight and suitable as dwarfing stocks in a breeding program with timber-type 

 chestnuts. 



No new work was undertaken on this project. 



Wood Quality 



Three wood quality symposia were held during 1959 and 1960, initiated by 

 the Department of Lands and Forests and sponsored by the Advisory Committee 

 on Forestry and Forest Products. As a result of these meetings a Wood Quality 

 Unit was established within the Research Branch, Department of Lands and Forests 

 in June 1962, and the Ontario Research Foundation was engaged on an annual 

 contract to develop a program under the guidance of an Advisory Committee, con- 

 sisting of appropriate heads of staff in the Research Branch, Faculty of Forestry, 



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