pith ray


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Related to pith ray: wood ray

pith ray

[′pith ‚rā]
(botany)

medullary ray, pith ray

medullary rays
In a cross section of a tree or log, one of the ribbons of tissue extending radially from the pith; may vary from microscopic to 4 in. (10 cm) or more in oak; used to store and transport food horizontally within the tree.
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