as aspen hybrid that roots well from stem cuttings has largely been solved. Many 

 hybrids with 75-90% rooting ability have been produced. The most promising of 

 the crosses are being repeated and promising individuals are being tested in respect 

 to other valuable attributes. 



1ARD PINES 



The objectives of the hard pine breeding project are to produce a red pine 



>r red pine-like tree resistant to the pine shoot moth and of satisfactory growth 



ite and growth form. Selection for a shoot moth-resistant red pine has 



;en unsuccessful because of the genetic uniformity of this species. In the spring of 



1963, an intensive effort was made to cross red pine with other closely related 



species. Seeds from these crosses matured in the fall of 1964 and have been sown 



a greenhouse. If some of the 3,000-4,000 seedlings produced are hybrids, they 



n\\ play an important role in introducing genetic variability into red pine. 



Reforestation Research 



Research in all aspects of artificial regeneration, is aimed at the technical and 

 ;ientific improvement of the reforestation programme. Studies are conducted in 

 le greenhouse, in nurseries and in planting areas. 



IURSERY AND PLANTING STUDIES 



In certain studies the effects of treatments applied in the nursery must be 

 examined for several years after outplanting. One large project, dealing with cor- 

 recting the acidity of nursery soils, has required a test-planting programme lasting 

 several years. Results indicate that artificial acidification can produce important 

 improvements in the quality of planting stock. Another study, relating to mulching 

 practices of the nurseries, has shown the use of hardwood sawdust as a mulch, 

 offers immediate benefits in more efficient use of seed and in reduction of main- 

 tenance costs. 



This year, a study was started to examine the effects of the nursery fertilization 

 programme on the quality of the stock as measured in terms of planting success, 

 in which both survival and growth are considered. Variations in the fertilizer pro- 

 gramme were applied to experimental areas in several nurseries. Selected stock 

 from these areas will be planted and the results observed carefully. 



Studies have continued in several areas across the province on the compari- 

 sons of seedlings with transplants for general planting. Also, aspects of the effects 

 of different planting methods on the survival and growth of several species have 

 been examined. 



Work was also started this year on the effects of cultivation on the improve- 

 ment of growth in plantations. This will be a long-term study, but the practice has 

 been economically advantageous in other countries. 



FROST DAMAGE STUDIES 



Frosts have caused much loss and damage in the tree planting programme. 

 Research has been directed to the identification of frost damage in wood, ways of 

 measuring frost damage, and investigations of frost hardiness differences between 

 and within species. 



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