Kan Ke (Sugiwara no Michizane)
At the present time,
Since no offering I could bring,
See, Mount Tamuke!
Here are brocades of red leaves,
At the pleasure of the god.
You who understand
may follow me to the
red mountain's slope —
and there accept
what only gods
Risa is remembering that her best years were spent earning a meager living on the mountainsides in all seasons and all weathers. Fall foliage has come to symbolize those years for her, as a sign of the turning of the year. It is something to be loved for itself, and cannot be sold or even given away -- only experienced.
Michizane, a courtier active in the 800s C.E., was also a scholar and teacher. He was exiled by the emperor, and a series of misfortunes followed, with catastrophes to the capital and the royal family. Subsequently Michizane's good name was restored in an effort to propitiate his spirit, and he is now a Shinto deity. His poems in the Chinese manner are considered especially good.
Hokusai's Old Nurse visualizes the Emperor's cart travelling (to a shrine) in autumn, the time of year referenced in the poem, with red leaves descending all round. Michizane would have had to wait to make his offering after the Emperor was done doing so, and his poem makes the leaves themselves an offering which would never have to wait -- a leveling sort of poem that could be taken as subversive: in effect, "we are all equal before the gods." The oxen have balked, and the cart is, at the moment, going nowhere -- possibly a reference to the oxen that carried Michizane to his grave, and which also balked.