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Union Strength

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Strength of the union where branches meet the trunk depends on at least three main factors: 1) branch diameter relative to the trunk, 2) angle of departure, and 3) presence of inclusions. The photo on the left shows this nicely. The smaller branch on the right side is well secured to the trunk because there is no inclusion, the angle of departure is fairly wide, and the aspect ratio is small. A small aspect ratio means that the branch is small relative to the trunk. The branch on the left has three problems: it is fairly large in comparison to the trunk, there is a bark inclusion in the union, and the angle between branch and trunk is very narrow. Branches trained like the one on the right side are well secured to the trunk, those growing like the left branch are not.

More examples: 1 | 2

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