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我场系黄土丘陵地带,海拔高610米左右,坡度4——5 度,土壤属碳酸盐栗钙土、很瘠薄,酸碱度7.5——8.4。气候变化无常,冬季严寒,夏季酷热,无霜期105天左右,年平均风速3——4米/秒,降雨量250——300公厘,多集中于7——8月间,而蒸发量达1,753毫米,是一个比较干燥寒冷的地区。党和政府为了发展林业生产,改变自然面貌,于1956年在这里建立了国营林场。三年来除积极营造大面积用材林外,共造桑树经济林3,848亩,平均成活率93%以上,平均高2米左右,粗1.5厘米以上。去年养了春蚕34张,收入人民币562.74元,今年计划产桑叶四万斤,养蚕48张,明年就可以大量养蚕。获得以上丰产成绩的经验是:
My field of loess hilly areas, about 610 meters above sea level, the slope of 4 - 5 degrees, the soil is carbonate chestnut soil, very barren, pH 7.5--8.4. Climate change is impermanence, the winter is cold, hot in summer, frost-free period of about 105 days, the annual average wind speed of 3 - 4 m / s, rainfall 250 - 300 mm, mostly concentrated in the 7 - August, while the evaporation of 1,753 Mm, is a relatively dry and cold area. In 1956, the state and the government established state-owned forest farms here in order to develop forestry production and change the natural appearance. In the past three years, a total area of 3,848 mu of mulberry economic forest has been built in addition to a large area of afforestation timber, with an average survival rate of 93% or more. The average height is about 2 meters and the diameter is more than 1.5 centimeters. Last year raised 34 spring silkworms, with a revenue of 562.74 yuan. This year plans to produce 40,000 mulberry leaves and 48 sericulture silkworms. This year, a large number of silkworms will be reared. The experience gained above is: