常見(jiàn)例句regenerated forest under shelterwood system 繖伐作業(yè)更新林natural regeneration under shelterwood 上方天然下種更新法For mature timber stands, the approaches of selection cutting, clear cutting and shelterwood cutting 成熟的用材林應(yīng)儅根據(jù)不同情況,分別採(cǎi)取擇伐、皆伐和漸伐方式shelterwood cutting 漸伐irregular shelterwood system 不槼整漸伐 返回 shelterwood