Change in First Leaf and Bloom Dates Between 1951–1960 and 2014–2023

This indicator shows modeled trends in lilac and honeysuckle first leaf dates at weather stations across the contiguous 48 states. This map compares the average first leaf date during two 10-year periods, developed using data from the USA National Phenology Network. Blue circles represent later leaf dates, and red circles represent earlier. For more information: https://www.epa.gov/climate-indicators