Among eight native North American willow species examined for coppice growth performance, the sand dune willow, Salix cordata Michx. (COR) has proved to be one of the most productive and useful for woody biomass production. In a common garden study, clones from the eastern and southwestern regions of Ontario, Canada, outperformed those from northern populations. Geographic region, populations within regions, and clones within populations all accounted for large portions of total variation in coppice growth traits that were compared with two other willows commonly used for biomass production, S. discolor Muhl. and S. eriocephala Muhl. Each species varied significantly in coppice structure and growth. The number of coppice stems per plant (coppice stem number) showed strong positive relationships to stem dry mass in 1- and 3-year-old coppices. Female COR plants were often slightly larger than male plants in this dioecious species, but these differences were not statistically significant, and provided no evidence of a reproductive cost expressed as a differential reduction in subsequent vegetative growth in female vs. male plants. This indicated that a zero sum model in which reproductive and vegetative structures compete for assimilates was not supported by our results. In all three species, clonal selection for growth and commercial biomass production, coppice stem number (not plant sex, longest stem length or corresponding basal stem diameter) was the best criteria for selecting superior willow clones.

在检查了矮林生长性能的八种北美本土柳树中，沙丘柳树Salix cordata Michx。(COR) 已被证明是最有生产力和最有用的木质生物质生产之一。在一项普通的花园研究中，来自加拿大安大略省东部和西南部地区的克隆人的表现优于来自北部种群的克隆人。与另外两种通常用于生物量生产的柳树S. discolor Muhl相比，地理区域、区域内种群和种群内克隆都占了矮林生长性状总变异的很大一部分。和S. eriocephala穆尔。每个物种在矮林结构和生长方面都有显着差异。每株植物的矮林茎数（矮林茎数）与 1 年和 3 年生矮林的茎干质量呈强正相关。在这种雌雄异株的物种中，雌性 COR 植物通常略大于雄性植物，但这些差异在统计学上并不显着，并且没有提供生殖成本的证据，该繁殖成本表现为雌性植物与雄性植物随后的营养生长的差异减少。这表明我们的结果不支持生殖结构和营养结构竞争同化物的零和模型。在所有三个物种中，生长和商业生物量生产的克隆选择、矮林茎数（不是植物性别、