Momichiba wa ima wa utsurou wagimoko ga matamu to iishi toki no heyukeba

黄葉は今はうつろふ我妹子が
待たむと言ひし時の経ゆけば

Roma-ji: Momichiba wa ima wa utsurou wagimoko ga matamu to iishi toki no heyukeba
English Translation: The yellow leaves
are fading now and falling,
for the time my wife
said that she would wait for me
has begun to pass away
Meaning: The yellow leaves are fading now and falling, for the time my dear wife said she would wait for is slipping away.
Commentary: Book Fifteen Poems of the Envoys to Silla 3713

Headnote continued from the preceding poem: "Eighteen poems composed while anchored at Takashiki Bay, each expressing his feelings"
He sings that the yellow leaves are now fading and falling because the time his wife said she would wait for is passing away. In 3701 of this book, by the vice-ambassador, seeing the yellow leaves made him realize the time his wife awaited had come; here that time has passed further still, and he laments that the leaves too are fading. The turning of the leaves shows the promised time of return slipping by in vain.
According to the headnote, this is one of eighteen poems composed while anchored at Takashiki Bay, each expressing his feelings. Takashiki Bay lies within Asō Bay in Tsushima, thought to be present-day Takeshiki in Mitsushima, Tsushima City, Nagasaki Prefecture. The last nine poems of the sequence have no left notes, and the author of this poem is not named.

First line, "momichiba wa": the leaves colored in autumn.
Second line, "ima wa utsurou": "utsurou" means to fade, to change: the leaves past their peak and falling. The poem breaks after the second line.
Third line, "wagimoko ga": my dear wife.
Fourth line, "matamu to iishi": which she said she would wait for, the same line as the fourth line of 3701 of this book.
Fifth line, "toki no heyukeba": "heyuku" means time passing on: since that time is passing. By inversion it gives at the end the reason for the second line.
Source: Manyoshu
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