自然整枝

树干通直、自然整枝良好、色彩富于变化有利于提高景观的美景度，而林木密度、林下层总盖度和林下层高度过高或过低（矮）都会给景观美学质量带来负面影响；

Trunk straight , better natural pruning , plentiful color variation do good to scenic beauty , while stand density , coverage of undergrowth and height of undergrowth being too high or too low do harm to scenic beauty .

而马尾松的树高生长虽然较快，但自然整枝较差，树干不通直，且虫害较严重，抗性差；

P. massoniana showed fast height growth but poor natural trimming , crooked bole , low insect pest resistance .

研究了不同大小树木的死枝和节子大小及其变化规律，分析了枝条的生长、被压、寿命和自然整枝过程，评价了节子大小和分布对木材质量的影响；

Dead branches or knots in different sizes of tree was studied and different branch development phases of growth , suppression , death and self-pruning was analyzed to evaluate the effect that knot size and distribution impact on timber quality .