Some wood seems to have structures that are squarish in cross-section. I've often noticed that these are distributed in arcs or sinusoid shapes on guitar fretboards, for instance.

Here's an example I was able to find online: fretboard Edit: here's a better picture, you can see the pattern as it rotates with respect to the cutting plane I think: body

Are they channels or just fibers of a different color? Why are they distributed in this way?

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    $\begingroup$ Welcome to Biology.SE. I see a lot of different patterns — I think it could be helpful to indicate (e.g. by adding markings like arrowheads) exactly what structures you are interested in. It also would be clearer if you showed a plain piece of wood (ideally a closeup of a small section of wood) rather than a fretboard, which complicates the issue. Next, if you are using some else's image it should be public domain and properly credited. Finally, have you tried looking up "wood anatomy"? Demonstration of prior effort on your part is one of the site expectations (see: tour, How to Ask, and help center). $\endgroup$
    – tyersome
    Commented Jul 16, 2022 at 2:28
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    $\begingroup$ I suggest looking for wood cell patterns online. also is that a natural pattern or is a veneer which involves cutting a wood in a rotary slice. google.com/… $\endgroup$
    – John
    Commented Jul 17, 2022 at 1:53

1 Answer 1


Wood is composed of a variety of longitudinal cells (those running parallel to the axis of the trunk or limb) and ray cells (those running perpendicular to that axis, from the center of the trunk to the edge).

Longitudinal cells produce the regular ring pattern (you can see them aligned vertically in the fingerboard photo). Rays (also called medullary rays, vascular rays, or pith rays) are producing the darker squiggles.

The ray cells help conduct sap and other materials radially in the trunk, between the center and the bark.

Different types of wood produce more or less prominent rays, with different characteristics. Different cuts of wood also make the rays more or less visible.


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