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一、前言造林的主要目的在于生产木材,以供应国家建设的需要。山东本省不仅森林少,而现在适于建筑用材的乡土树种尤少。如侧柏是山东石灰岩和紫色页岩山上主要造林树种,但生长极慢,一般要到七、八十年以上才能成材。油松、赤松是山东中性和微酸性土的山地上主要造林树种,但各种虫害非常严重,生长亦较缓慢,材质亦非建筑良材,因此有引种外来树种的必要。
I. Preface The main purpose of afforestation is to produce wood to supply the needs of national construction. Shandong Province, not only less than the forest, and now suitable for building materials native species rarely. For example, oriental arborvitae is the main afforestation species in Shandong limestone and purple shale. However, it grows extremely slowly, and generally it takes more than seven to eighty years to grow up. Pinus tabulaeformis and Pinus sylvestris are the main afforestation species in the mountainous area of Shandong Province, which are of neutral and slightly acidic soil. However, all kinds of pests are very serious and grow slowly. The materials are not good for building materials, so it is necessary to introduce alien tree species.