When to tap maple trees in Maine

Maple season in Maine usually opens early March and winds down mid-April. Here's the long-run pattern, the year-by-year record, and what the forecast says right now.

Typical season
Opens
March 4
Closes
April 11
Recent openings ranged
Feb 26 – Mar 21 (2011–2022)
Typical length
About 35 days
Sap-flow outlook right now

Forecast for Jackman

Updated Sep 26, 5:43 AM EDT

It's the off-season. Sap needs freezing nights, and there are none in sight. Maine's season usually opens around March 4 — 159 days from now.

No freeze-thaw days in the forecast

Blue = below 32°F · Amber = thaw · dashed line = freezing

  1. SunSep 27
    62°high
    47°low
    0h frozen
    24h thawed
    No freeze, no run
  2. MonSep 28
    54°high
    47°low
    0h frozen
    24h thawed
    No freeze, no run
  3. TueSep 29
    58°high
    48°low
    0h frozen
    24h thawed
    No freeze, no run
  4. WedSep 30
    65°high
    47°low
    0h frozen
    24h thawed
    No freeze, no run
  5. ThuOct 1
    69°high
    48°low
    0h frozen
    24h thawed
    No freeze, no run
  6. FriOct 2
    65°high
    50°low
    0h frozen
    21h thawed
    No freeze, no run

Data: National Weather Service. Verdicts use freeze-thaw thresholds from maple field research; your woods may run a little differently.

Full Maine sap forecast →
Maine seasons, 2011–2022
JanFebMarAprMaymedian start Mar 420112011: Mar 10 – Apr 1320122012: Feb 28 – Mar 2820132013: Mar 4 – Apr 1220142014: Mar 21 – Apr 1920152015: Mar 21 – Apr 1720162016: Feb 26 – Apr 920172017: Mar 2 – Apr 1220182018: Feb 26 – Apr 920192019: Mar 14 – Apr 1420202020: Feb 29 – Apr 820212021: Mar 6 – Apr 620222022: Mar 4 – Apr 9
Each bar is one season, from the approximate average opening date to closing date reported by USDA NASS.
How to know it's time

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.

NASS state averages are weighted toward Somerset County in western Maine, which has 86.6% of the state's taps. UMaine Extension: freeze/thaw sap weather typically runs mid-February to early April in southern Maine and mid-March to late April in northern Maine.

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

  1. USDA NASS — Maple Syrup Production — news release, June 2013 (average open/close dates 2011–2013) — USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  2. USDA NASS — Maple Syrup Production — news release, June 2014 (average open/close dates 2012–2014) — USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  3. USDA NASS — United States Maple Syrup Production, June 11, 2015 (average open/close dates 2013–2015) — USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  4. USDA NASS — United States Maple Syrup Production, June 15, 2016 (average open/close dates 2014–2016) — USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  5. USDA NASS — United States Maple Syrup Production, June 14, 2017 (average open/close dates 2015–2017) — USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  6. USDA NASS — United States Maple Syrup Production, June 13, 2018 (average open/close dates 2016–2018) — USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  7. USDA NASS — United States Maple Syrup Production, June 12, 2019 (average open/close dates 2017–2019) — USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  8. USDA NASS — Crop Production, June 2020 — maple syrup tables (average open/close dates 2018–2020) — USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  9. USDA NASS — Crop Production, June 2021 — maple syrup tables (average open/close dates 2019–2021) — USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  10. USDA NASS — Crop Production, June 2022 — maple syrup tables (average open/close dates 2020–2022) — USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  11. USDA NASS — Crop Production, June 2023 — maple syrup tables (average open/close dates 2021–2022; discontinued 2023) — USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  12. Bulletin #7036, How to Tap Maple Trees and Make Maple Syrup — University of Maine Cooperative Extension
  13. In 100 years, maple sap will flow a month earlier — Cornell Chronicle
  14. USDA 2022 Census of Agriculture, County Data — Table 37. Maple Syrup: 2022 and 2017 (Maine) — USDA National Agricultural Statistics Service
  15. 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 Maine?
Usually from early March to mid-April — about 5 weeks. The exact start moves by weeks from year to year with the weather.
When should I tap my trees in Maine?
Tap just before the first good run: when the forecast shows nights below freezing and days climbing to around 40°F. In a typical year that's around March 4. 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.
Other states
ConnecticutIllinoisIndianaIowaKentuckyMassachusettsMichiganMinnesotaMissouriNew HampshireNew YorkOhioPennsylvaniaVermontWest VirginiaWisconsin

Get a heads-up when Maine's sap will run

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