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湿地松、火炬松是我国三十年代以来从美国引进的优良造林树种。我省最早于一九四七年引进湿地松、火炬松种子,一九五一年播种育苗,一九五二年开始造林。这批树至今在长沙市尚保存母树62株(湿地松27株,火炬松35株),一九八一年经湖南省国外松引种协作组实地调查,三十年生的湿地松平均树高12.7米,平均胸径29.68厘米;火炬松平均树高14.1米,平均胸径32.19厘米。我市引种推广,进行成片造林是一九七
Pinus elliottii and Pinus taeda are the excellent tree species introduced from the United States since the 1930s. As early as 1947, the province introduced the seeds of Pinus elliottii and Loblolly pine and seeding nurseries in 1951 and reforestation in 1952. So far, 62 trees of mother trees (27 of slash pine and 35 of loblolly pine) have been preserved in Changsha City. In 1981, the survey was conducted by the Cooperative Group of Foreign Pine Introduction in Hunan Province. The average tree height of 30-year-old Pinus elliottii was 12.7 The average diameter at breast height is 29.68 cm. The average height of loblolly pine is 14.1 meters and the average diameter at breast height is 32.19 cm. Introduced to promote the city, into a piece of afforestation is 197