Autumnal Equinox the date when day and night are equal -- or, at these latitudes, about as close as they get. The berries, Oregon grape, are one of the season's markers. Although bitter, they are edible and are reputed to make a better than passable jelly.
Aside from paying attention to the edibles I might forage this time of year, I have a couple of cleaning rituals that go along with this event. Some years, like this one, I get a break and don't have to do these until the 22nd. Some years, the equinox occurs as early as the 20th. But it's just our crazy calendar that causes that, not nature.
The hot tub gets fresh water, as does the Brita filter system in the kitchen. And sometimes, the cutlery drawer gets its grooves cleared too.
These traditions are partly my way of observing and honouring the change of seasons. They're also a sort of mnemonic device for a memory that doesn't always work as well as it used to, reminders that there are things I need to look after.
Maybe you have seasonal traditions as well. If you do, best wishes accomplishing them and going forward into a happy autumn, the season so many consider the most beautiful of all. It's a season that's not just beautiful to look at, but with its many arts events, it may well be the culturally richest time of year.