These features of the young stem wood rays accords with well-known earlier stages in ray ontogeny (see Barghoom, 1941; Carlquist, 1988) in angiosperms, as illustrated in those two sources for Bursera simaruba.
The tensile strength of isolated wood rays of beech (Fagus sylvatica L.) and its significance for the biomechanics of living trees.
This can be probably due to the existence of filled vessels with tylose and surrounding by longitudinal parenchyma with long branches, in addition to the existence of impenetrable wood rays
. In addition, alkaline liquor caused more shrinkage and swelling than neutral liquor and similar to the absorption, the difference between the shrinkage and swelling rates of radial and tangential directions was obvious in neutral liquor compared to alkaline liquor.
According to Sweitzer wood rays
are homocellular (consisting of procumbent cells only), whereas in all four of our specimens (the living and three herbarium collections) rays are heterocellular.
Red oak also has very large wood rays
. In contrast, hard maple has small-diameter pores uniformly distributed across each growth ring and much smaller wood rays
lie parallel to the inner and outer faces when well-quartered and prevent leakage in the horizontal plane.
Frye said the fine wood rays
of American beech yield a beautiful cross-fire figure when quartered.