为了提高杉木生产潜力,本所先后营建了杉木初级种子园和杉木种源种子园各6.67公顷,并已生产种子园混系种子4520kg,优良家系种子600kg;评选出杉木优良种源8个,优良单亲家系40个,优良双亲家系20个;推广杉木优良种源、优良家系和种子园种子造林近1万公顷。但其增产效益不同。从表1可以看 In order to improve the production potential of Chinese fir, the institute has successively constructed 6.67 hectares of Chinese fir primary seed orchards and Chinese fir seed orchards, and has produced 4520 kg of mixed seeds of seed orchards and 600 kg of fine family seeds. Eight excellent provenances of Chinese fir 40 single-parent families and 20 elite parents; popularized nearly 10,000 hectares of excellent provenances of cunninghamia, elite families and seeds of seed orchard. However, its production efficiency is different. Table 1 can be seen