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杉木生长快、产量高、林质好、用途广、是我区主要用材造林树种之一。但它在土山区,特别是桂北土山区生长较好,在丘陵地区、特别桂南低丘陵地区生长较差。原因是,前者气温较低,旱季较短,湿度较大,加以土质较肥,所有这些比较适合其生活特性的要求,后者的气候和土壤条件与前者相反,若栽培管理不善,针叶容易出现失绿病。在失绿病发展之后,会使枝叶枯萎,林木衰退。轻者不能长成大材,重者不能成林成材。要使杉木在低丘地
Fir grow fast, high yield, good forestry, wide use, is one of the main afforestation species in our area. However, it grows well in Tu mountain area, especially in Tu mountain area of Gui miang province. It grows poorly in hilly area, especially in low hilly area of southern Gui. The reason is that the former has lower temperature, shorter dry season, higher humidity and more soil fertility, all of which are more suitable for the requirements of their living characteristics. The latter has the opposite climate and soil conditions from the former. If the cultivation is poorly managed, the needles are easy Appear chlorosis. After the development of green leaf disease, will make the branches and leaves withered, trees decline. Light can not grow into large timber, heavy timber can not become a success. To make fir in the hilly ground