As the days grow longer and the air warms up, nature is bursting back to life. Even before their leaves return, trees produce delicate, fuzzy structures known as catkins. These tiny, downy threads, often described as kitten tails (thanks to a fun translation from Dutch to English back in 1578), herald the arrival of spring.

As for timing though, it’s a bit like a botanical ballet. Depending on the species and the year’s environmental conditions, catkins dance to their own beat. Hazels might kick off the floral festivities between January and March, while oaks take their turn between mid-April and May.

The global climate has been changing since the industrial era. Summers are getting warmer, rainfall patterns are fluctuating and extreme weather events will continue to get more frequent. Seasons are beginning to shift.