Growth performance and wood structure of wavy grain sycamore maple (Acer pseudoplatanus L.) in a progeny trial

• Key message Wavy grain, a rare figure type of wood, leads to highly priced timber in Acer pseudoplatanus L. The influence of this trait on growth performance and its causes are not known. Analyzed wavy and straight grain sycamore maple progenies show comparable growth performance in a field trial. Stability of wavy grain after vegetative propagation is confirmed and genetic inheritance indicated. • Context Wavy grain is a rare figure type of wood resulting from undulating fiber growth that leads to a decorative and highly priced timber in Acer pseudoplatanus L. with top positions on auction sales. Nevertheless, neither the influence of this trait on growth performance is known, nor have the causes been disentangled. • Aims Our objectives were to find out if wavy grain figure influences growth parameters essential for log quality and to gain insight into the causes of wavy grain by the analysis of a progeny trial and a seed orchard. • Methods In a progeny trial with 30-year-old F-1-offspring from selected wavy grained and straight grained trees, trunk diameter, tree height, and trunk shape were evaluated. Additionally, 21 trees of the trial and selected plus tree-grafts of a seed orchard were felled and analyzed for occurrence and intensity of wavy grain structure. • Results No effect of the wavy and straight grain parentage on growth was observed in the progeny trial. Of the felled trees, over 30% showed evidence of wavy grain compared to rare occurrence in natural stands. Wood structure analysis of plus tree scions confirmed the stability of wavy grain after vegetative propagation. • Conclusion Wavy grain seems to be genetically inherited, and there seems to be no statistically significant difference in commercially relevant traits in the progeny. This highlights the value of including wavy grain as a desired attribute in breeding systems of maple.