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Home → Publications → Tree Improvement and Genetics → Northeastern Forest Tree Improvement Conference → 30th Northeastern Forest Tree Improvement Conference (1987) → Four Years Height Growth of 25 Jack Pine (Pinus Banksiana Lamb.) Families in an Accelerated Nursery Trial

Four Years Height Growth of 25 Jack Pine (Pinus Banksiana Lamb.) Families in an Accelerated Nursery Trial

Heights at age one to four years were recorded in a nursery trial with 25 open-pollinated jack pine families. Narrow sense heritabilities decreased from 0.43 at age one to 0.27 at age four. This decrease is interpreted to be a consequence of increased competition following crown closure at age three. Genetic correlations of recorded tree heights were above 0.9 when first year measurements were excluded. First-year results were poorly correlated to subsequent heights (r G < 0.4). Calculations of genetic gain of tree height at age four showed that expected gain could be increased by either indirect selection at age two or by index selection. Indices of family ranking and height growth stability over time showed mainly random differentiation among families.


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Author(s): Steen Magnussen, C. W. Yeatman

Publication: Tree Improvement and Genetics - Northeastern Forest Tree Improvement Conference - 1987