interlocked grain
Helical grain in which the orientation of the grain oscillates with the increment of new wood from one side of the long axis of the stem to the other, so that the helix turns in one direction then the other (over a radial distance of millimetres or centimetres). Stems with interlocked grain are much more difficult to split than those with straight grain, and sawn wood with interlocked grain is difficult to plane.
This definition is abridged from A – Z of tree terms: A companion to British arboriculture.
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