【摘 要】
：
杂交杨的推广,近年来在各地有了较大的发展,这对于林木的速生丰产,尽快给国家提供大量木材,将起到深远的影响。我场从1968年开始引种杂交杨300余种。 通过育苗、造林实验,试
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杂交杨的推广,近年来在各地有了较大的发展,这对于林木的速生丰产,尽快给国家提供大量木材,将起到深远的影响。我场从1968年开始引种杂交杨300余种。 通过育苗、造林实验,试图逐步选出适合各种不同条件下的优良品种。遵照伟大领袖毛主席关于“推广优良品种”的教导,我们于1974年4月对1971年春定植的(二年生苗)几个品种进行了调查,表现好的有以下四种:
The popularization of hybrid poplar has made great development in various places in recent years, which will have a far-reaching impact on the fast-growing and high-yielding forest and providing a large amount of wood to the country as soon as possible. My field began in 1968 introduced hybrid Yang more than 300 species. Through nursery, afforestation experiments, trying to gradually select suitable varieties under different conditions of fine varieties. Following the teachings of Chairman Mao, the great leader, on “promoting good varieties,” we conducted several surveys on several varieties of colonized (two-year-old) plants in the spring of 1971 in April 1974, and performed well in the following four categories:
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