Parts of the South and Southeast are seeing their earliest spring on record this year, with leaves already budding on trees as much as three weeks early. Other parts of the South and Southeast are seeing their earliest spring in 40 years. Contrast that with southern Arizona, where they are seeing their latest start to spring in 40 years. The National Phenology Network, which keeps track of the arrival of spring, maps the locations where it believes spring has already arrived. …Much of the “early spring” has to do with the warm start to 2023. Much of the South and Southeast are off to their top-10 warmest years on record. …It is even more dramatic in the mid-Atlantic and Northeast. …The timing of when plants bloom is critical for the pollinators who depend on them. …It could have some really catastrophic effects on ecosystems,” O’Connell said.