Sapwood area - leaf area relationships for coast redwood

Coast redwood (Sequoia sempervirens (D. Don) Endl.) trees in different canopy strata and crown positions were sampled to develop relationships between sapwood cross-sectional area and projected leaf area. Sampling occurred during the summers of 2000 and 2001 and covered tree heights ranging from 7.7 to 45.2 m and diameters at breast height ranging from 9.4 to 92.7 cm. Foliage morphology varied greatly and was stratified into five types based on needle type (sun or shade) and twig color. A strong linear relationship existed between projected leaf area and sapwood area at breast height or sapwood at the base of the live crown despite the variability in foliage morphology. Ratios of leaf area to sapwood were 0.40 m(2)/cm(2) at breast height and 0.57 m(2)/cm(2) at crown base. Measurements of sapwood at the base of the live crown improved leaf area predictions because of sapwood taper below the crown base. A sapwood taper model was also developed.