classic waka stream

I do not know how
the cedars by the old stream
grew to what they are,
and yet I look at you as
the likeness of one now gone

Meaning
I do not know how the cedars by the old stream grew to what they are, and yet I look on you as the likeness of one now gone.
Commentary
Part Three: Tenarai

 The nun's reply. She does not know where the girl came from, she says frankly, but she looks at her as standing in her dead daughter's place. She had come to love Ukifune deeply as that likeness, and it was this that made her wish for the match with the Captain. Soon after, while she was away at Hatsuse, Ukifune took her vows.

 Motodachi is the way a tree has grown, and carries the sense of a person's origins, which she does not know. "One now gone" is her dead daughter, with sugi, gone by, playing on sugi, the cedar. She takes over the two cedars of the other poem and turns a refusal into a statement of affection, which shows the old nun's nature exactly.
Author
Murasaki Shikibu
Source
Genji Monogatari
Other