Mélange de clones en taillis à courtes rotations de peuplier : influence sur la productivité et l'homogénéité des produits récoltés

Two stands of short-rotation coppice of hybrid poplar were studied from age 3 to harvest (age 7 or 9). The performance of three clones planted at a density of 3000 stems/ha either in mixed- or mono-clonal stands was determined in each stand. Mean diameter and total biomass were not significantly different among the treatments (mixed- or mono-clonal stands). On the other hand, in mixed-clonal plots, biomass distribution was not equally distributed among clones. Diameter distribution was bimodal (two clones) or even trimodal (three clones). At one site (Tourtenay), mortality due to competition affected mostly the suppressed clone ('Boelare'). Mortality is significantly higher for this clone at age 7. With such closed spacings, competition occurs soon and social position is rapidly irreversible.