When to tap maple trees in Illinois
Maple season in Illinois usually opens early January (south) to mid-February (central) and winds down late February (south) to mid-March (central). Here's the long-run pattern, the year-by-year record, and what the forecast says right now.
- Opens
- early January (south) to mid-February (central)
- Closes
- late February (south) to mid-March (central)
Forecast for Funks Grove
Updated Sep 26, 8:36 AM EDT
No freeze-thaw days in the forecast
Blue = below 32°F · Amber = thaw · dashed line = freezing
- SunSep 27No freeze, no run73°high53°low0h frozen
24h thawed - MonSep 28No freeze, no run74°high51°low0h frozen
24h thawed - TueSep 29No freeze, no run77°high56°low0h frozen
24h thawed - WedSep 30No freeze, no run73°high63°low0h frozen
24h thawed - ThuOct 1No freeze, no run73°high65°low0h frozen
24h thawed - FriOct 2No freeze, no run72°high60°low0h frozen
20h thawed
Data: National Weather Service. Verdicts use freeze-thaw thresholds from maple field research; your woods may run a little differently.
Sap runs on a temperature swing, not a date. A night below freezing loads the tree; a day above freezing pushes sap out of the taphole. Field research treats a low under about 30°F followed by a high over about 37°F as a real freeze-thaw day, and big runs almost always come on days like that.
So watch the 10-day forecast. When you see a string of nights in the 20s and afternoons in the 40s, get your taps in a day or two ahead. Tap south-facing slopes first — they warm and run earlier.
No NASS season data for Illinois. Illinois Extension: in southern Illinois the season runs roughly from the first week of January into the last week of February, and later the farther north you go. In central Illinois, Funks Grove historically ran mid-February to mid-March, but the season "seems to get earlier each year" and producers are starting to tap earlier, maybe in January (WGLT, 2023).
Seasons are shifting. In New England and New York, the sugaring season now begins about 8 days earlier and ends about 11 days earlier than it did 40 years earlier, leaving it roughly 3 days (about 10%) shorter, according to UVM Proctor Maple Research Center survey records analyzed in 2007.
Plan your season
Sources
- Maple syrup season is a short, sweet window of opportunity for tapping into trees — Illinois Extension
- Climate change threatens central Illinois maple syrup production — WGLT (Illinois State University public radio)
- Statement of Timothy D. Perkins, Ph.D., Director, UVM Proctor Maple Research Center — Global Warming Mountaintop 'Summit': Economic Impacts on New England (June 4, 2007) — U.S. House Select Committee on Energy Independence and Global Warming
Common questions
- When is maple syrup season in Illinois?
- Usually from early January (south) to mid-February (central) to late February (south) to mid-March (central). The exact start moves by weeks from year to year with the weather.
- When should I tap my trees in Illinois?
- Tap just before the first good run: when the forecast shows nights below freezing and days climbing to around 40°F. Tapholes dry up within 6 to 10 weeks, so tapping far too early can cost you the late runs.
- What weather makes sap run?
- Freezing nights and thawing days. Field research counts a freeze-thaw day as a low under about 30°F and a high over about 37°F; nights in the 20s and days in the 40s are the classic sap days.
Get a heads-up when Illinois's sap will run
LuckySap checks the forecast for your trees and can ping you the night before a strong sap day — then keeps every collection and boil in one season log. Free on iPhone.
