The seventy-second and final kō of the traditional calendar. 乳 here doesn't mean "milk" but is used for laying/nesting behavior — hens, whose winter laying drops sharply as daylight hours shorten, begin returning to their coop (とや, toya) to nest and lay again as the days imperceptibly start lengthening past the solstice. For a household with no modern lighting or feed science, a hen resuming egg-laying after a long winter pause was a small, reliable, repeatable proof that the year had genuinely turned — arriving, by design, in the calendar's very last few days.
The traditional calendar's own cycle closes here in the same spirit it's held all along: not with a dramatic final flourish, but with something ordinary and domestic quietly resuming. Chickens were historically kept in Japan largely as ornamental, time-announcing birds rather than food animals — their crowing sacred enough that it became, centuries earlier, the origin of a Man'yōshū pillow-word for the eastern provinces, 鶏が鳴く (tori ga naku, "the rooster crows"), used to introduce 東 (Azuma) simply because a rooster's cry announces the east's dawn first.
Still in excellent season through the year's final cold stretch.
At peak richness, a fitting note to close the winter table on.
Late-season fruit, still sweet and widely available.
Continuing from the previous two kō — the calendar's very last stretch still tastes distinctly of early spring pushing through.
Still in excellent season, a steady presence across nearly the whole winter run of kō.
Ume's earliest buds can begin opening in sheltered spots right at the calendar's close — a fitting overlap, since plum blossom is traditionally the very first flower associated with spring's arrival, making its debut appearance right as this calendar's own year quietly ends and, the next day, begins again.
Falling on the day immediately after this kō's window closes — the last day of the old year in the seasonal, rather than lunar, reckoning, immediately before Risshun (立春, the traditional first day of spring). Setsubun's mamemaki (豆まき, bean-scattering) ritual, chanting "鬼は外、福は内" ("demons out, fortune in") while throwing roasted soybeans, descends from an older Heian court exorcism ritual called 追儺 (tsuina); the roasted beans were credited with a kind of protective force, both for driving off the bad luck of the old year as it closes and, eaten afterward, for bringing a share of that force into the new one.
"The rooster crows" — A Man'yōshū-era pillow word (枕詞) attached specifically to 東 (Azuma, "the east" or the eastern provinces) — used because a rooster's crow announces the coming of dawn first from the east, so the phrase became a fixed poetic label for the direction itself, appearing across numerous Man'yōshū poems.
乳 (nyū/chichi) ordinarily means milk or nursing, but functions here as an old term for a bird returning to nest and lay — one more instance, closing out the whole calendar, of a familiar character carrying a specialized older meaning that has otherwise fallen out of everyday use.
Setsubun's mamemaki ritual traces to 追儺 (tsuina), a Heian-era court ceremony for driving off unseen malevolent spirits at the year's turn, which gradually spread from court practice into a household custom performed nationwide.
Roasted soybeans, thrown while chanting "鬼は外、福は内," are sold seasonally at nearly every Japanese supermarket in the days beforehand.
A small, deliberate preview of Risshun and the new year of kō about to begin the day after this one closes.
"The one I long for with every breath — is he crossing the eastern hills, where the rooster crows, today?"
The lengthening daylight driving this kō's namesake behavior only continues to lengthen from this point through spring.
In the traditional seasonal calendar this genuinely was New Year's Eve — the biggest reason mamemaki still carries the weight it does.
This poem's writer can't see the road her thoughts are traveling — only imagine it, breath by breath, using a direction a rooster's cry gave a name to long before she was born. It's a fitting note to close the whole calendar on: seventy-two kō built from careful, close observation of things actually seen — geese arriving, frost first forming, ice thickening by measurable degrees — ending instead on someone reaching toward what she can only picture. The observed world and the imagined one turn out to need each other by the end. What have you been picturing all year that you still can't quite see?