Microseason: Insects Retreat Underground

The 47th (of 72) microseason of the year in Japan is Insects Retreat Underground 蟄虫坏戸 (Mushi kakurete to wo fusagu). It is the second microseason of the Autumn Equinox solar term. In 2026, it is on for five days from September 28th to October 2nd. 

The name comes from the belief that insects and other small creatures begin disappearing into the soil as temperatures cool. The character 蟄 refers to creatures hiding away, while 坏戸 describes shutting or sealing a door. Together, they create the image of insects closing the entrance to their winter shelters. After months spent buzzing, chirping, and crawling through fields and gardens, they begin their retreat beneath the ground where they will remain until spring.

For farmers of yore, this was another sign that the growing season was drawing to an end. The fading songs of crickets and the disappearance of insects reflected the changing conditions in the fieds. As autumn deepened, attention turned towards harvesting crops and preparing for the colder months ahead. While moder farming relies on weather forecasts and technology, seasonal changes in insect activity can still provide clues about important transitions.

Even today, signs of this microseason apply and are easy to find. The evenings feel quieter than they did earlier in September, and fewer insects seem to be active after sunset. Shops continue filling their shelves with autumn favorites such as sweet potatoes, chestnuts, pumpkins, and seasonal beverages. I am already seeing tints of color in some leaves and plants. The beauty of autumn is fast approaching while insects are retreating underground!