The opening and the closing lines of the first stanza of the poem have been repeated. While the opening line “What does he plant who plants a tree?” comes thrice in the poem, the stanza-closing “These things he plants who plants a tree.” occurs twice. 
 
These recurring lines help each stanza to form a logical whole, with one asking a question and the other summing up the answer. In between goes the poet’s reply to the initial question regarding the greatness of a man who plants a tree. With these repetitions the poem has only been more concrete and easier to understand.