Survival and growth of black and white spruce seedlings in relation to stock type, site preparation and plantation type in southeastern Manitoba

Differences in survival and growth of black and white spruce seedlings plan ted on boreal mixedwood sites were tested for stock types (transplant versu s container), site preparation (Donaren disc trenching versus no trenching) , and plantation types (open versus sheltered) in southeastern Manitoba aft er eight or nine growing seasons. Mortality of open plantation (32.3%) and container stock (32.5%) were significantly higher than sheltered plantation (23.7%) and transplant stock (22.8%), respectively. Donaren trenching slig htly reduced the mortality of black spruce but significantly increased the mortality of white spruce. Seedlings of container stock (110 cm) were signi ficantly shorter than transplant stock (157 cm). Significant difference in height was found between open and sheltered plantations for black spruce bu t not for white spruce. Root collar diameter of container stock (15.6 mm) w as significantly smaller than transplant stock (23.1 mm). Root collar diame ter in sheltered plantations was significantly larger than that in open pla ntations for black spruce but not for white spruce. Black spruce open plant ation had significantly smaller volume (97 cm(3)) compare to black spruce s heltered (210 cm(3)) and white spruce open (175 cm(3)) and sheltered (229 c m(3)) plantations. White spruce open plantations also had smaller volume th an white spruce sheltered plantations. Container stock had smaller volume ( 89 cm(3)) than transplant stock (267 cm(3)). For transplant stock, strip pl antations had a significantly higher volume (329 cm(3)) than open plantatio ns (204 cm(3)). Based on above results, we recommend that (1) transplant st ock should be used, (2) sheltered plantation site preparation should be use d on boreal mixedwood sites, and (3) Donaren disc-trenching is not necessar y for planting white spruce.