觀無量壽佛經義疏 2.105

2.105

「『見此樹已，亦當次第一一觀之，觀見樹莖枝莖華果皆令分明。』」恐其參亂，故令次觀。莖等五種，即是次第。莖謂根幹，必兼枝條。三、結示。

"‘Having seen these trees, one should also contemplate them one by one in sequence, seeing the tree trunks, branches, foliage, flowers, and fruits, making them all clear and distinct.’" Fearing they might become confused, [the Buddha] causes one to contemplate them sequentially. The five items from trunk onward are the sequence itself. "Trunk" means the root and bole, which necessarily includes the branches. Third, concluding instruction.