... competition from herba-ceous vegetation for seedlings of jack pine, black spruce, and whitepine, New For. 21 (2001) 199–215.[20] Philipson J.J., Coutts M.P., Effects of growth hormone application on ... 6,27]. Removal of thewhorl and lateral buds and whorl branches had a more severeeffect on plant growth and caused a reduction in root length and DW. Removal of a significant part of the photosyntheticarea ... and greenery quality, Proceedings from the inter-national Christmas tree and greenery research and extension con-ference 31, July – 3. August, Denmark. Danish Centre for Forest,Landscape and...