classic waka stream

A buried tree that
never came into flower—
and now at the end
my body has borne its fruit,
and bitter the bearing is

Meaning
A buried tree that never came into flower—and now at the last my life has borne its fruit, and bitter that fruit is.
Commentary
Volume Four: The Prince's Last Hour

 Once Ashikaga Tadatsuna had crossed the Uji, the fighting at the Byōdō-in grew fierce. Yorimasa's second son Kanetsuna took an arrow inside his helmet and, faltering, was seized and thrown by Jirōmaru, a page of the governor of Kazusa and a man of great strength. Kanetsuna, wounded but famously strong himself, pinned him and took his head; but as he rose, fourteen or fifteen Taira warriors fell on him together and killed him. The heir, Nakatsuna, Governor of Izu, fought hard, took many wounds, and killed himself in the fishing pavilion of the Byōdō-in; Shimokōbe Tōzaburō Kiyochika took his head and flung it under the great floor. Nakaie, Chamberlain of Rokujō, and his son Nakamitsu also fought hard, took many heads, and died. Nakaie was the heir of Yoshikata; orphaned when his father was killed, he had been adopted by Yorimasa and treated with kindness, and perhaps not to break a long-standing promise, he died in the same place.
 Yorimasa summoned Watanabe no Chōshichi Tonau and told him to take his head. Tonau, unwilling to strike his living lord, said he could not do it, but would take it after Yorimasa had killed himself. Yorimasa allowed that this was right, faced west, joined his hands, and chanted the Buddha's name ten times aloud. His last words were this poem.
 It was no time to be composing poems, the tale notes, but he had loved the art too helplessly since youth to forget it even then. He set the point of his sword to his belly, fell forward upon it, and died. Tonau took the head, slipped away through the press, tied it to a stone, and sank it in a deep place in the Uji.

 An umoregi is a tree buried in earth: it does not flower, and no one knows of it. Yorimasa went long without advancement, and as the next chapter tells, it was by composing poems that he was at last admitted to the palace and then raised to the third rank. Here he takes that buried tree for himself.
 Mi no naru puns on "the fruit forms" and "the body comes to be." That fruit should form on a tree which never flowered is impossible; the impossible has happened to him, and it is his end. The fruit borne by a tree that never flowered is a rebellion at seventy-five, and this suicide.
 The poem answers the verse the old monk Gōun quoted in Volume One: deep among the hills it could not be told apart, yet the cherry has revealed itself by its blossoms. There, what was hidden appears as flower; here, a tree that never flowered bears only fruit. The Tale of the Heike encloses Yorimasa's life between two poems about blossoming.

umoregi……a tree buried in the earth; a figure for a life unknown to the world.
mi no naru……a pun on fruit forming and a body coming to its state.
hate……the end; the last.
Sanmi no Nyūdō……Yorimasa, who took vows after his promotion to the junior third rank.
jūnen……ten invocations of Amida's name.
tsuridono……a pavilion built out over a pond in shinden architecture.
Chōshichi Tonau……Watanabe no Tonau, Yorimasa's retainer.
tatewaki no senjō……the head of the guards attending the crown prince.
Source
Heike Monogatari
Other