衢州河谷低丘红壤地域,年际水热配合非常适合柑桔生长,但年极端最低气温-7℃—-11.8℃的频率(1970—1981年)高达33.3—41.6%(平均2—3年一遇),成为常规“一年种、三年养树、四年始果投产”的柑桔大株稀植栽培法的限制因子。为此,在这种柑桔冻害频繁的地段,除选择山地逆温层 In the red soil region of Quzhou valley, intertropical hydrothermal co-ordination is very suitable for the growth of citrus. However, the frequency of extreme extreme minimum temperature -7 ℃ -11.8 ℃ (1970-1981) is as high as 33.3-41.6% (average 2-3 years Case), a conventional “one year, three years of raising the tree, four years put into operation fruit” citrus sparse plant cultivation method of limiting factor. To this end, frequent citrus freeze damage in the lot, in addition to the selection of mountain inversion layer