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毛白杨13个无性系及新疆杨测定林(简称测定林)座落在山东冠县苗圃三林区。该地处黄河故道,占地25亩。土壤为轻砂质潮土,土质均匀,肥力较低,pH值为7.5,地下水位3—4米;最高气温42℃,最低气温-21℃;无霜期200天,年平均降水量600毫米。 测定林于1979年3月栽植,对比排列,对照为山东毛白杨(雄株)。定植后
Thirteen clones of Populus tomentosa and Xinjiang Yanglin Forest (referred to as the measured forest) are located in Sanlin District, Guan County Nursery. The Yellow River is located in the old course, covering 25 acres. Soil is light sandy tidal soil, soil quality, low fertility, pH 7.5, groundwater level 3-4 meters; maximum temperature 42 ℃, minimum temperature -21 ℃; frost-free period 200 days, the average annual rainfall of 600 mm. Forest measured in March 1979 planted, compared to the control of Shandong Poplar (male). After planting