Latewood density in relation to wood fibre diameter, wall thickness, and fibre and vessel percentages in Quercus robur L.

Abstract

To elucidate the influence of growth rate and cambial age on latewood density in oak (Quercus robur L.), the diameter and wall thickness of libriform fibres, and percentage of latewood area occupied by libriform fibres and vessels, were analysed across discs of ten 87-year-old oak trees from Germany. Fibre wall material per unit fibre area did not vary significantly with cambial age, since increase in fibre diameter with ring number from the pith was offset by increase in wall thickness. There were no significant variations in fibre diameter or wall thickness with latewood width. Changes in latewood density with cambial age or with growth rate were primarily associated with changes in tissue percentages per unit area, latewood density being more closely correlated with vessel than with fibre percentages. There appeared to be a curvilinear relationship between latewood width and latewood density, density reaching a maximum when latewood width was about 2 mm.