顺序地模拟符合植物学生物特征的复杂树结构会占用很多计算机资源。为减少对计算机资源的占用，提出了一种从最简单的子结构起，通过子结构的引用来形成复杂结构的方法。由于在该方法中重复出现的结构只被计算一次，因此不仅可以提高复杂结构的计算速度，而且可以降低几何信息的存储量。该几何信息不仅包括所模拟植物在各个生长周期的结构，而且包括了每个子结构的具体形态。尽管这是一种自上而下的算法，但由于子结构方法能够实现弯曲枝条的模拟，并能产生重复生长的结构和花序结构，因此具有通用性。

Sequential simulation of 3D geometry of complex plant that is faithful to botany may occupy a lot of computer resources. In this paper, a method of building complex structures begun by the simplest stems is presented; the simpler substructures are pasted recursively to form more complicated branches. In doing that, the repetitive structure in plant is computed only once, and then can be reused according to its index, thus this method can increase computation speed of complex tree structure, and decrease storage size for the geometrical information as well. These information includes not only geometrical data of the simulated plant at each growth cycle, such as orientation and position of each botanical organ, but also that of each substructure. Although substructure method is a top-down algorithm that is inverse to growth sequence of plant growth, it is shown in this paper that bending branches can still be simulated in this way, as well as reiteration and inflorescence structures, which shows the generality of this method.