Find out when the biological start of spring will occur on your refuge and how this year's spring stacks up to a long term average.
The Spring First Leaf Index is a synthetic measure of early season events in plants, based on recent temperature conditions. This model allows us to track the progression of spring onset across the country.
The Status of Spring tool has three maps:
1. Where has spring arrived? - This maps shows where early spring plant and animal activity has begun, based on the First Leaf Index
2. Spring forecast - This map shows where early spring plant and animal activity is expected to begin in the next six days
3. How does this year stack up? - This map compares the timing of the start of spring this year to the long-term average (1981-2010)