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The typical components and physical／chemical characteristics of the ash were introduced based on the relative research works carried out all around the world, as well as its influences on plants, upper soil layer vegetation, soil microbial population and environment after application. Generally, this kind of ash has low potassium content, but high pH value due to high Ca content. It’s a good remedy for acid soil. The high pH value is also valuable for improving composition of soil microorganism, enhancing their activities and thereafter increasing the fertility of soil. Meanwhile, the ash is rich in certain elements, which are critical to modify the elements constitution of soil and increase the availability of N and K in usual situation. As far as current research is concerned, the fertilization of wood ash achieves element circle, improves soil characteristic to some degree.