Radial Variation and Growth Rate in the Length of the Axial Elements Of Sessile Oak Wood

Abstract

Radial variability of the axial element length in oak-wood is most prominent in the juvenile wood which inc1udes approximately 30 annual rings. The length of fibres, tracheids and vessel elements increases from the pith outwards according to a second degree curve. This dependence is most apparent for wood fibres, whereas it is the least distinct for vesseI elements. In the mature zone, anatomical elements are, on average, 10 to 20% Ion ger than in juvenile wood. With deteriorating conditions of tree growth, the length of the anatomical elements tends to increase. There is a negative correlation between length of the measured elements and growth ring width; this is most c1early so for fibres. A similar relationship exists between the length of anatomical elements and wood density.