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从一九七三年,我场开始营造速生丰产林,六年来,已发展到四百余亩.主要树种是欧美杨(前称科伦158)、健杨等,另有少量北京杨、太青杨。土壤系沂河冲积沙壤土或冲积沙。有机质含量0—0.2％,PH值6.5—8.5,地下水位0.7—1.5米,立地条件较差。经过整地改土,加强扶育初步取得成效.杨树丰产林年生长量较差的也在1立方米以上;中等的2立方米,少数好的3立方米以上.现将栽培技术措施,叙述如下:
Since 1973, the farm has started to build fast-growing and high-yield forests. Over the past six years, it has grown to more than 400 acres. The main tree species are the European and American poplars (formerly known as Kelun 158), Jian Yang, etc. In addition, Green Young. Soil Yi River alluvial sandy loam or alluvial sand. Organic matter content 0-0.2%, PH value 6.5-8.5, groundwater level 0.7-1.5 meters, site conditions are poor. After soil preparation and improvement of fertility, the initial success has been achieved. The annual growth rate of poplar-rich forest is also more than 1 cubic meter; medium 2 cubic meters, a few good 3 cubic meters above the cultivation techniques and measures described below :