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Home → Publications → Tree Planters' Notes → Tree Planters' Notes Volume 61, Number 2 (2018) → Two-Year Stem Curvature and Growth Responses of Three Full-Sibling Families of Loblolly Pine to Five Root/Stem Form Treatments

Two-Year Stem Curvature and Growth Responses of Three Full-Sibling Families of Loblolly Pine to Five Root/Stem Form Treatments

To examine the effects of taproot deformity on stem curvature, 90 full-sibling loblolly pine (Pinus taeda L.) seedlings (30 seedlings each from 3 families) were planted with 5 root/stem form treatments: straight taproot (control treatment), straight taproot with underground obstruction, taproot planted with J-root form, taproot planted at a 45-degree angle, and a straight taproot with the stem pulled to a 45-degree angle. Significant treatment differences (P ≤ 0.05) were found in year 1 for stem diameter and frequency of interwhorl oscillations, and all variables differed significantly among families. Although no significant treatment effects existed in year 2, family differences in diameter at breast height, height, and frequency remained significant. In addition, amplitude of stem curvature was significant for the treatment-by-family interaction in year 2. No differences were found for treatment, family, or their interaction for stem biomass. Results suggest that stem curvature responses of loblolly pine were more attributable to genetics than to root/stem form.


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Author(s): Michael S. Murphy, Laurence R. Schimleck, Timothy B. Harrington, Richard F. Daniels

Publication: Tree Planters' Notes - Volume 61, Number 2 (2018)

Volume: 61

Number: 2