Towards a New Model of Branch Attachment

Slater, Duncan; Harbinson, C.

doi:10.1080/03071375.2010.9747599

Cited by 20 publications

(13 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The most evident inconsistency is the fact that cambial activity occurs simultaneously in ring-porous species [8,12]. Shigo's hypothesis has rarely been tested scientifically, apart from Dan Neely's research in the 1990s and Duncan Slater's research from 2010 onwards [13][14][15]. Neely undertook a series of experiments in the early 1990s injecting different species of trees with a water-soluble dye, methyl violet, at the branch-to-stem junction.…”

Section: Issues and Challengesmentioning

confidence: 99%

Demystifying Tree Forks: Vices and Virtues of Forks in Arboriculture

Christophe¹,

David²,

Duncan³

2020

J Bot Res

View full text Add to dashboard Cite

Parallel to this, all tree forks are regarded in many arboricultural texts as inherently weak structures, regardless of their specific nature. The afore-mentioned guide states that "[c]odominant stems are inherently weak because the stems are of similar diameter" [1]. Considering a fork as inherently weak, justified only based on axes ratio is not founded on persuasive or extensive scientific study.When we look at a mature tree developing through a strategy of reiteration that has established a strong, solid and stable main fork as a result of a long and progressive architectural metamorphosis, we are witnessing that all forks are not weak structures. Certain forks, especially main forks, are so strong, solid and stable that they may be the most reliable structure formed in the tree, capable of supporting the entire broad-crown and its wind-induced oscillations. Terminological Approach to Tree ForksThe botanical term for a junction yielding two or more equivalent axes that form sharp angles between them is 'a fork'. However, forks have also been referred to as 'codominant stems' in arboriculture since the early 1970s, a term that is strongly established. The term 'co-dominant stems' can be traced, in forestry literature, all the way back to the 19th century, originating in the English translations of the crown classification system by Gustav Kraft, which was published in Ger-

show abstract

Section: Issues and Challengesmentioning

confidence: 99%

Demystifying Tree Forks: Vices and Virtues of Forks in Arboriculture

Christophe¹,

David²,

Duncan³

2020

J Bot Res

View full text Add to dashboard Cite

show abstract

“…Therefore, Shigo concluded that 'the trunk tissue from above the branch does not connect with the branch' (Shigo 1986). Slater and Harbinson (2010) argued, however, that branch and stem may be connected by, for example sclereids tissue. Such tissue plays no significant role in water transport, and therefore, it would not conduct dye, but it provides mechanical support.…”

Section: Hypothesis and Models For Fibre Orientation Around Knotsmentioning

confidence: 99%

Growth layer and fibre orientation around knots in Norway spruce: a laboratory investigation

Briggert

Olsson

et al. 2017

Wood Sci Technol

View full text Add to dashboard Cite

The strength of structural timber largely depends on the occurrence of knots and on the local material directions in the surroundings of such knots. There is, however, a lack of methods for establishing a full dataset of the local material directions. The present research aims at the development and application of a laboratory method to assess the geometry of growth layers and the orientation of fibres in a high-resolution 3D grid within wood specimens containing knots. The laboratory method was based on optical flatbed scanning and laser scanning, the former resulting in surface images and the latter, utilizing the tracheid effect, resulting in in-plane fibre angles determined in high-resolution grids on scanned surfaces. A rectangular solid wood specimen containing a single knot was cut from a tree in such a way that it could be assumed that a plane of symmetry existed in the specimen. By splitting the specimen through this plane through the centre line of the knot, two new specimens with assumed identical but mirrored properties were achieved. On one of the new specimens, the longitudinal-radial plane was subsequently scanned, and the longitudinal-tangential plane was scanned on the other. Then, by repeatedly planing off material on both specimens followed by scanning of the new surfaces that gradually appeared, 3D coordinate positions along different growth layers and 3D orientation of fibres in a 3D grid were obtained. Comparisons between detected fibre orientation and growth layer geometry were used for the assessment of the accuracy obtained regarding 3D fibre orientation. It was shown that the suggested method is well suited to capture growth layer surfaces and that it provides reliable information on 3D fibre orientation close to knots. Such knowledge is of great importance for understanding the properties of timber including

show abstract

“…Lignified vascular bundles in dicotyledons are mostly arranged in a distinct vascular cylinder from which they proceed into the branch (Shigo 1985;Slater and Harbinson 2010) and are not distributed in a parenchymatous matrix, as for example, shown in Dracaena (Haushahn et al 2014;Hesse et al 2016;Masselter et al 2016). Nevertheless, the morphology and ontogenetic development of a coherent vascular system from a main stem into a side axis in dicotyledons is of high interest in the context of novel structures to be used in fiber-reinforced materials, as it often involves the contribution of various vascular bundle derivatives (Zimmermann and Tomlinson 1972;Larson 1983Larson , 1984Larson , 1986aTomlinson et al 2005;Schwager et al 2015) and may result in conspicuous branching morphologies, such as in the Araliaceae genus Schefflera (Tomlinson et al 2005).…”

Section: Electronic Supplementary Materialsmentioning

confidence: 99%

Branching morphology, vascular bundle arrangement and ontogenetic development in leaf insertion zones and ramifications of three arborescent Araliaceae species

Bunk

Fink

Speck

et al. 2017

Trees

View full text Add to dashboard Cite

Key message A conspicuous 'finger-like' branching morphology is described for three arborescent Araliaceae species with a focus on the three-dimensional vascular bundle arrangement in leaf insertion and stem-branch attachment regions during ontogenetic development. Abstract The central aim of this study is to gain a deeper understanding of the structure and development in leaf insertions and stem-branch attachments of the arborescent Araliaceae species: Schefflera arboricola, Fatsia japonica and Polyscias balfouriana. Therefore, the vascular bundle arrangement in the leaf insertion zone and ontogenetic development of the stem-branch attachment after decapitation were analyzed, with a special focus on their conspicuous 'finger-like' branching morphology that, to our knowledge, is unique to the Araliaceae. Decortication of adult ramifications allows for a morphological analysis of the woody strands in the stem-branch attachment regions. Via high-resolution microscopy of serial thin-sections and 3D reconstructions, as well as cryotome sections, anatomical analysis was carried out of the course and arrangement of vascular bundles through leaf insertions and later developing ramifications, including a comparative analysis of the different ontogenetic stages. All three species investigated present a 'finger-like' branching morphology with variations in the number and arrangement of the woody strands. Thin-sectioning reveals a conspicuous pattern of leaf trace emergence from the main stem, proceeding into the leaf and the early developing ramifications. Vascular bundle derivatives contribute to the vascular integration of leaves and axillary buds. The described 'finger-like' branching morphology in the investigated Araliaceae species represents a sophisticated mode of vascular integration in leaf insertion zones and developing ramifications. In combination with forthcoming biomechanical experiments, this analysis shall serve as a basis for biomimetic translations into textile technology (fiber-reinforced branched composite materials) and civil engineering (optimization of branched building structures).

show abstract

Towards a New Model of Branch Attachment

Cited by 20 publications

References 10 publications

Demystifying Tree Forks: Vices and Virtues of Forks in Arboriculture

Demystifying Tree Forks: Vices and Virtues of Forks in Arboriculture

Growth layer and fibre orientation around knots in Norway spruce: a laboratory investigation

Branching morphology, vascular bundle arrangement and ontogenetic development in leaf insertion zones and ramifications of three arborescent Araliaceae species

Contact Info

Product

Resources

About