Climate sensitivity of wood-anatomical features in a ring-porous oak (Quercusmacrocarpa)

Anatomical characters of the early- and late-wood of individuals of a ring-porous oak (bur oak, Quercusmacrocarpa Michx.) growing in southeastern Nebraska display sensitivity to yearly variations in precipitation. Characteristics of the latewood increment (latewood vessel diameter and density) are closely related to ring width, with vessel diameter varying directly and vessel density varying inversely with ring width. Various analyses indicate that ring width appears to be a less direct climatic indicator than latewood vessel diameter in these trees. A regression equation incorporating latewood vessel diameter is used successfully to reconstruct precipitation over a 9-month period (October–June).