<p>Forests are expected to become more frequently and severely damaged by pests and wind due to climate change. Removing assimilative parts from tree crown can result in growth reduction and potentially affect wood properties. Although there may be intraspecific variation in trait responses to defoliation, only limited information is available. This study aimed to assess the effects of artificial defoliation treatments with different intensity on tree growth and wood properties of Japanese cedar clones in young plantations, and evaluate whether different clones respond differently to defoliation. Two years after the treatments, tree height and diameter growth were assessed. Stress wave velocity (SWV) and Pilodyn penetration depth (PP) were measured as indicators of wood stiffness and density. Defoliation negatively impacted tree growth and had a slightly greater effect on diameter growth than on height growth. Compared to the clearly negative effects of defoliation on tree growth, the magnitude of its effect on wood properties was limited, and a slight defoliation effect was observed in PP but not in SWV. The ranking of clones in terms of growth or wood properties remained consistent across intact and defoliated conditions, with clones that performed better under intact conditions also tending to perform better under defoliated conditions. Although increasing defoliation intensity significantly reduced tree growth, the present results highlight the importance of planting superior genotypes with higher growth rates and better wood properties.</p>