PubMed · 2026-04-24
Scientists tracked how three common European trees — oak, beech, and spruce — build their water-transport plumbing each growing season, finding that ring-porous oaks like sessile oak have a split personality: early-season wood is highly conductive but vulnerable, while later wood adds bulk with little hydraulic payoff. Beech and spruce, by contrast, grow and gain water-moving capacity in near-lockstep.
Ring-porous oak shows a clear mismatch between when it adds wood mass (basal area increment) and when it gains or loses hydraulic conductivity — the two curves are out of phase within the same growing season.
Diffuse-porous beech and conifer spruce show tightly coordinated growth and hydraulic gain, meaning a simple delayed growth curve can estimate their water-transport capacity at any point in the season.
Oak vessels are progressively occluded by tyloses (internal plugs) as the season advances, causing measurable conductivity loss even while the ring is still growing — a dynamic not seen in beech or spruce.
