我省和本刊曾对武清县东洲大队创造的榆树“冬打头,夏控侧” 的修枝经验进过行宣传和推广,并编写了《怎样种榆树》一书(1974年河北人民出版社出版)和刊登了“管理榆树的哲学”(1973年河北林业科技资料第10—11期)等文章。因此,这一经验对我省林业生产有着广泛的影响。正值科学繁荣的今天,我们收到了武清县农林局胡自强同志“白榆幼树修枝技术的初步探讨”一稿,对上述经验通过一定的试验和观察,提出了一些不同的看法。为了使科学不断得到发展,我们本着“百花齐放,百家争鸣”的方针,发起对这一问题的讨论,请广大林业科技工作者根据工作的亲身体验或研究结果发表自己的见解,寄给本刊编辑组,以便陆续刊登。 My province and the magazine had on Wuqing County Dongzhou brigade created elm “winter head, summer control side” pruning experience into the line of publicity and promotion, and the preparation of “what kind of elm” (1974 Hebei people Publishing house) and published “philosophy of managing elm” (1973, Hebei Forestry Science and Technology Information No. 10-11) and other articles. Therefore, this experience has a broad impact on forestry production in our province. At a time when science is prosperous, we received a manuscript from Comrade Hu Ziqiang of Wuqing Agriculture and Forestry Bureau, “Preliminary Study on the Cultivation Techniques of Saplings of Ulmus pumila”. Some different opinions have been put forward through some experiments and observations. In order to keep the development of science, we initiated the discussion on this issue in line with the policy of “letting a hundred flowers bloom and a hundred schools of thought contend.” We invite our forestry scientists and technologists to express their opinions based on the personal experience or research results of their work and send them to our editors Group, in order to publish one after another.