Photo/IllutrationCherry blossoms flower along the Megurogawa river in Tokyo on Oct. 17. (Shun Matsumoto)

Dusk in autumn often evokes feelings of nostalgia.

Listening to the chirping of bugs and gazing at cirrocumulus clouds in the sky, haiku poet Sanki Saito (1900-1962) recalled sights and sounds from his elementary school days--the clanging of a bell from the ruins of a castle above his school, and a flock of raucous crows that looked like black sesame seeds scattered in the darkening sky.

Saito also noted in an essay that while the crows cawed, he and his mates headed home, each on their own way.

Our ears, eyes and skin “feel” those twilight hours while the nights become progressively longer.

I recently learned that plants also sense the lengthening of nights.

According to plant physiologist Osamu Tanaka, leaves “measure” the length of nights.

Tanaka reasons that plants perhaps need to know the changing of the seasons in advance if they are to time their budding and flowering right.

I thought that photosynthesis was the only job of leaves, but I have probably underestimated their role.

Out-of-season cherry blossoms are being reported across Japan, which is also believed to have something to do with the physiology of leaves.

Around this season, the leaves secrete plant hormones that regulate the growth of flower buds. But having been buffeted by typhoon winds containing seawater sprays, many leaves fell off. Coupled with prolonged unseasonably warm weather, the buds simply kept growing.

Hoping to enjoy cherry blossoms in the refreshing autumn air, I strolled along the Megurogawa river in Tokyo. Upon close scrutiny, I saw a white blossom or two, here and there. It appears that most of the buds will wait until spring to open.

The Japanese expression for out-of-season flowering is “kurui-zaki,” which literally translates as “insane flowering.”

This implies that the plants have gone crazy, which is not kind.

Just like us, the trees have been forced to suffer the consequences of the continuation of abnormal weather in this country.

--The Asahi Shimbun, Oct. 19

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Vox Populi, Vox Dei is a popular daily column that takes up a wide range of topics, including culture, arts and social trends and developments. Written by veteran Asahi Shimbun writers, the column provides useful perspectives on and insights into contemporary Japan and its culture.