Skip to content
LuckySap
Get the app
Michigan · county maple atlas

Maple sugaring in Eaton County, Michigan

Eaton County had 27 maple operations and 18,705 taps in the 2022 Census. Around Charlotte, sap usually runs from February 24 to March 28. Here's the long-run pattern, 36 seasons of sap weather, and the outlook this week.
Too early to tapAbout 141 days until the usual start.
Sap starts
Feb 24
typical year
Season ends
Mar 28
about 5 weeks
Sap days / season
37.7
1991–2026 average
Taps, 2022
18,705
#9 of 66 in MI

Sap-flow outlook at Charlotte right now

Full Michigan forecast →

Forecast for Charlotte, MI

Updated Oct 6, 11:03 AM EDT

Off-season for now. Sap needs freezing nights, and none are in sight. Eaton County's season usually opens around February 24, which is 141 days away.

No freeze-thaw days in the forecast

freeze thaw 32°F

  1. WedOct 7
    53° / 71°

    0h below · 24h above

    No refreeze forecast
  2. ThuOct 8
    48° / 64°

    0h below · 24h above

    No refreeze forecast
  3. FriOct 9
    42° / 66°

    0h below · 24h above

    No refreeze forecast
  4. SatOct 10
    45° / 72°

    0h below · 24h above

    No refreeze forecast
  5. SunOct 11
    53° / 74°

    0h below · 24h above

    No refreeze forecast
  6. MonOct 12
    52° / 71°
    No refreeze forecast

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

When the sap runs

The sugaring calendar at Charlotte

Freeze-thaw weather at Charlotte peaks in the weeks of Feb 23 to Apr 6, which hold about 49% of a season's sap days. March is the busiest month.
Typical season: Feb 24 – Mar 280246Week of Dec 1: 1.5 sap days on averageWeek of Dec 8: 1.9 sap days on averageWeek of Dec 15: 1.5 sap days on averageWeek of Dec 22: 1.5 sap days on averageWeek of Dec 29: 1.1 sap days on averageWeek of Jan 5: 1.2 sap days on averageWeek of Jan 12: 0.9 sap days on averageWeek of Jan 19: 0.7 sap days on averageWeek of Jan 26: 0.9 sap days on averageWeek of Feb 2: 1.4 sap days on averageWeek of Feb 9: 1.6 sap days on averageWeek of Feb 16: 1.9 sap days on averageWeek of Feb 23: 2.1 sap days on averageWeek of Mar 2: 2.6 sap days on averageWeek of Mar 9: 2.7 sap days on averageWeek of Mar 16: 3.3 sap days on averageWeek of Mar 23: 3.1 sap days on averageWeek of Mar 30: 2.6 sap days on averageWeek of Apr 6: 2.2 sap days on averageWeek of Apr 13: 1.3 sap days on averageWeek of Apr 20: 0.9 sap days on averageWeek of Apr 27: 0.4 sap days on averageWeek of May 4: 0.2 sap days on averageWeek of May 11: 0.1 sap days on averageWeek of May 18: 0.0 sap days on averageWeek of May 25: 0.0 sap days on averageDecJanFebMarAprMaytaps in ~Feb 24
Average number of freeze-thaw sap days in each week of the season at Charlotte, 1991–2026. A sap day is an overnight low under 30.2 °F followed by an afternoon high over 37.4 °F. The shaded band is the typical season.

Year-to-year spread

Opening signal
Median Feb 28; the middle half of seasons fell between Feb 22 and Mar 6. Earliest Jan 31 (2017), latest Mar 13 (2014).
Closing signal
Median Mar 31; middle half between Mar 25 and Apr 5. Earliest Mar 3 (2024), latest Apr 17 (2014).
Sap days by month
Dec19%Jan11%Feb19%Mar34%Apr17%May1%

36 seasons of sap weather

Eaton County seasons, 1991–2026

The best sap year at Charlotte was 2018 with 53 freeze-thaw days; the leanest was 2010 with 24. Seasons that start early tend to end early too: the trees run on the swing between freezing nights and mild days, and heat ends it.
JanFebMarAprMaysap days20262026: Feb 12 – Mar 19, 33 sap days3320252025: Feb 22 – Mar 27, 37 sap days3720242024: Feb 3 – Mar 3, 40 sap days4020232023: Feb 27 – Apr 3, 48 sap days4820222022: Mar 3 – Apr 3, 44 sap days4420212021: Feb 23 – Mar 22, 36 sap days3620202020: Feb 23 – Mar 25, 39 sap days3920192019: Mar 4 – Apr 2, 37 sap days3720182018: Mar 9 – Apr 11, 53 sap days5320172017: Jan 31 – Mar 6, 32 sap days3220162016: Feb 16 – Mar 23, 47 sap days4720152015: Mar 8 – Apr 5, 28 sap days2820142014: Mar 13 – Apr 17, 29 sap days2920132013: Mar 12 – Apr 14, 43 sap days4320122012: Feb 10 – Mar 12, 43 sap days4320112011: Mar 7 – Apr 3, 25 sap days2520102010: Mar 1 – Mar 31, 24 sap days2420092009: Feb 26 – Mar 31, 34 sap days3420082008: Mar 12 – Apr 5, 28 sap days2820072007: Feb 20 – Mar 21, 28 sap days2820062006: Feb 24 – Mar 28, 33 sap days3320052005: Mar 3 – Mar 29, 31 sap days3120042004: Feb 23 – Mar 25, 41 sap days4120032003: Mar 8 – Apr 1, 27 sap days2720022002: Feb 24 – Mar 31, 49 sap days4920012001: Mar 6 – Apr 5, 32 sap days3220002000: Feb 28 – Mar 7, 41 sap days4119991999: Feb 27 – Mar 29, 52 sap days5219981998: Feb 21 – Mar 25, 35 sap days3519971997: Feb 28 – Apr 2, 43 sap days4319961996: Mar 10 – Apr 12, 51 sap days5119951995: Feb 20 – Mar 26, 37 sap days3719941994: Mar 6 – Apr 8, 46 sap days4619931993: Mar 12 – Apr 14, 31 sap days3119921992: Mar 6 – Apr 9, 39 sap days3919911991: Feb 20 – Mar 25, 40 sap days40
Each bar runs from the season's opening signal to its closing signal, estimated from daily temperatures at Charlotte. Dashed lines mark the typical dates. The right column counts freeze-thaw sap days from December through May.

Maple production

Eaton County in the Census of Agriculture

USDA counts maple operations every five years. In Eaton County the 2022 Census found 27 farms making syrup (-4% since 2017), with taps -27% and syrup output -19% over the same five years. That works out to about 0.20 gallons of syrup per tap in 2022 (0.18 in 2017). Among the 385 counties in this atlas, Eaton County ranks 95 by taps.

Eaton County maple production, 2017 and 2022 (USDA Census of Agriculture)
Census yearFarmsTapsGallons of syrupGal / tap
20222718,7053,8400.20
20172825,7304,7480.18

Nearby

Neighboring maple counties

Distances are between reference towns; typical dates are each county's own estimate.

About these numbers

The season dates are estimated from 36 seasons of daily high and low temperatures for the PRISM 4-km grid cell at Charlotte (902ft), scored with the same freeze-thaw rule as our live forecast: a sap day is an overnight low under 30.2 °F followed by an afternoon high over 37.4 °F. Each season's closing signal is the last sap day before accumulated warmth reaches a threshold, and the opening signal sits five weeks before that, never earlier than the first real freeze-thaw week. Tested against 117 state-seasons of USDA-reported dates, the rule lands within 5.5 days of the reported close and 6.6 days of the reported opening on average, and the typical dates shown here are scaled to Michigan's USDA record (12 years). Production figures are copied from the Census as published. Full method, calibration tables and the downloadable dataset →

Sources · 6

  1. 1.2022 Census of Agriculture, County Level Data — Michigan, Table 37: Maple Syrup, 2022 and 2017 · USDA National Agricultural Statistics Service
  2. 2.PRISM daily temperature grids (AN81d, 4 km), accessed 2026-10-05 · PRISM Group, Oregon State University, https://prism.oregonstate.edu
  3. 3.Applied Climate Information System (ACIS) web services · NOAA Regional Climate Centers
  4. 4.USDA NASS maple syrup reports — approximate average season opened and closed dates, 2011–2022 · USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  5. 5.Sap flow in sugar maple: timing and weather drivers (Frontiers in Agronomy, 2025) · de Lima Santos et al.
  6. 6.GeoNames gazetteer (cities500), CC BY 4.0 · GeoNames

FAQ

Eaton County sugaring questions

When should I tap maple trees in Eaton County, Michigan?
In a typical year the sap starts running around February 24 near Charlotte and the season winds down around March 28. Have your taps in a day or two before the first forecast string of freezing nights and 40 °F days. In the past 36 seasons the weather signal came as early as Jan 31 and as late as Mar 13.
How much maple syrup does Eaton County produce?
The 2022 Census of Agriculture counted 27 maple operations in Eaton County with 18,705 taps producing 3,840 gallons of syrup, ranking 9 of 66 Michigan's counties with published tap counts.
How many sap days does Eaton County get in a season?
On average 37.7 freeze-thaw sap days from December through May at Charlotte, of which about 12.9 are textbook days with a night in the 20s and a day in the 40s. The best season since 1991 was 2018 (53 sap days); the leanest was 2010 (24).
Where do these dates come from?
From 36 seasons of daily high and low temperatures at Charlotte (PRISM 4-km grid), scored with the same freeze-thaw rule as our live forecast, then calibrated against USDA's reported season dates for Michigan. They describe a typical year at one point in the county; your sugarbush, slope and elevation can shift them by days.

LuckySap · free on iPhone & Android

Get a heads-up when the sap will run in Eaton County

LuckySap watches 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 and Android.

Download on the App StoreGet it on Google Play