classic waka stream

Out of the paired leaves,
why was it the fallen one
that I gathered up,
when in name they are two twined
ornaments close to each other

Meaning
Out of the paired leaves, why was it the fallen one I gathered up, when in name the two are ornaments twined close together?
Commentary
Part Two: Wakana Ge

 After that night Kashiwagi grew more distracted still, and spent his days sighing whether he rose or lay down. His wife, the Second Princess, was a daughter of Suzaku as well, but her mother had been of lower rank and he had never taken her as the one he wanted. Sitting with her cleared nothing, and he let this poem fall. The name by which she is known in the tale, the Fallen Leaf Princess, comes from it. After his death she is loved by Yugiri, and carries a second story through the later part of Part Two.

 "The paired leaves" is the ornament of hollyhock and katsura worn at the Kamo festival, two things making one, and because of that pairing the word stands for sisters. "The fallen one" is a leaf on the ground, and it makes the elder sister the lesser of the two. "Ornament" is the thing worn in the hair and also sounds a shoot from the same branch, that is, a sister. That he could put anything so insulting to his wife into a poem at all shows how far his self-command had gone.
Author
Murasaki Shikibu
Source
Genji Monogatari
Other