Fruit Trees for Merrill, Antigo and Tomahawk, Wisconsin

In the cold wave of mid-February 1936, NOAA's Merrill station, down by the Wisconsin River at 1,250 feet, bottomed out at −39°F. Antigo, 27 miles east and about 270 feet higher, bottomed out at −27°F. The higher town ran 12°F warmer, and that's the first thing to know about fruit trees for Merrill, Antigo and Tomahawk: up here the cold follows the low ground, not the elevation. This map covers Lincoln County and western Langlade County in North Central Wisconsin, from Merrill up the Wisconsin River valley to Tomahawk, east across Gleason and the Harrison Hills to the Antigo Flats, and north through the kettle country to Elcho and Pelican Lake.

Type your address in the box on the map to get the number for your own place, and the list of what we sell that has come through it.

How to read this map

The big number is the 30-year planning low, the same number our cold hardiness calculator gives, plus a small adjustment for the ground right where you are. It's the bad night to plan around, not the record and not a forecast of how often it comes. The MFTC zone puts it in half zones. The typical winter is an average year's coldest night, the kind of average USDA's zones use. The spring layer shows how much warmer or colder a spot runs than Merrill on a still, clear night at bloom.

Merrill, the reference town, plans for −37°F, MFTC zone 3a, with a typical winter of −24°F. The middle of the map plans for −37°F, and half the growing ground plans for −38°F to −36°F. The mild end is the Antigo Flats and the high benches (Antigo and Chase Hill near Irma at −34°F, the benches around Pine River near −32°F). The cold end is the Tomahawk stretch of the Wisconsin and the upper Prairie River, where Dudley and Parrish plan for −39°F, Tomahawk plans for −38°F and the coldest tenth of the ground around Tomahawk hits −40°F. Most of the map is 3a; the Flats and the best benches are 3b.

Why the map looks the way it does

The cold goes where the water goes. The Wisconsin River runs down the west side of the map, through Lake Mohawksin at Tomahawk and over Grandfather Falls to Merrill, picking up the Prairie River at Merrill, while up in the northeast corner the Wolf heads off toward Lake Michigan. On a clear, calm night the ground radiates its heat to the sky, the air against it chills and gets heavy, and it slides downhill to the lowest ground it can reach: here, the Wisconsin River below Merrill, around 1,250 feet. The high ground is in the moraines, up to 1,920 feet at Lookout Mountain in the Harrison Hills, the highest point on the whole Ice Age Trail.

That's why Merrill runs colder than Antigo despite sitting about 270 feet lower. Over 65 years of NOAA records the Merrill station has run a median 3°F colder than Antigo for the year's coldest night, and some nights the gap blows open: −39°F to −27°F in 1936, −35°F to −23°F around March 1, 1962. Merrill sits in the river valley where the Prairie comes in, the low point for miles of rolling till country. Antigo sits on the Antigo Flats, a glacial outwash plain about 23 by 17 miles that meltwater streams spread out in sheets of sand and gravel. It's so level that within 3 miles of town the coldest tenth of the ground plans for −35°F and the warmest −34°F, with no deep trough for the cold to collect in. What counts on a still night is how far you sit above the nearest low ground.

Not every night sorts that way. On January 18, 1967, Antigo hit −39°F, its record, while Merrill's low in that outbreak was −35°F, and in January 1972 every station here read −38°F to −40°F. When arctic air pours in on a wind, the air stays mixed and higher ground has no edge; the map follows the clear, calm mornings after the front passes.

The Tomahawk end is the coldest ground on the map. The old Tomahawk Spirit Reservoir station (1917 to 1976) and the Rice Reservoir station up the Tomahawk River (since 1999) each run a median 3°F colder than Merrill, and Spirit Reservoir holds the lowest reading inside the map, −45°F on January 18, 1967. Tomahawk sits 20 miles north of Merrill at an elbow of the Wisconsin, and the town of Bradley around it is about 13 percent water (flowages and reservoirs) set in low, wet lake-and-bog ground. A wide, shallow basin like that can pool cold harder than a deep valley that drains. The water doesn't help in midwinter. These northern lakes freeze over every winter, and as Wisconsin's State Climatology Office puts it, lakes shelter their shores only when they're relatively free of ice.

North and east of the Flats the glaciers left another kind of trap. The Parrish and Summit Lake moraines are hummocky ground, and most of the lakes and bogs around Summit Lake and Elcho are kettles, hollows where buried blocks of ice melted out. A closed hollow fills with cold air up to its lowest notch before it spills, and the 1947 Langlade County soil survey found the county's muck ground getting later spring and earlier fall frosts because cold air drains into it. In 1894 Weather Bureau director Willis Moore told central Wisconsin cranberry growers their marshes often ran 10°F to 20°F colder than town, because loose, dry peat gives up its heat fast. The old Koepenick station, about 16 miles north of Antigo in this country, ran a median 5°F colder than Antigo.

The flip side is the thermal belt, the band of slope that stays mild on still nights, up out of the pool and below the windswept tops. Spring frost layers usually top out 30 to 200 feet up. Chase Hill, northeast of Irma, shows it best: 290 feet above its floor, it plans for −34°F against Irma's −37°F, 2 miles away, and reads 14°F warmer than Merrill on a still bloom night. Towns hold a little heat too, and the map gives built-up ground up to 2.5°F. Then there's snow, usually on the ground from late November: air over it runs colder, but 4 to 10 inches of it insulates the soil well.

Merrill, Pine River and the Wisconsin River bottoms

Merrill, the Lincoln County seat, started as the logging town of Jenny Bull Falls where the Prairie meets the Wisconsin. The map puts downtown on a toe slope 10 feet above the floor at 1,266 feet, planning for −37°F, MFTC 3a, with a typical winter of −24°F. Within 3 miles the floor plans for −38°F and the benches −35°F, so the slopes climbing out of the valley run 2°F to 3°F better than the river bottoms down toward Council Grounds State Park. Prairie River Savannah, about 3 miles northeast of downtown, sits in a river bottom at 1,308 feet and plans for −37°F, with benches nearby at −34°F. Even the thermometers disagree: the long-record Merrill station (1,250 feet) has averaged −23°F for the year's coldest night since 1995, the automated airport station a mile northwest −27°F.

Pine River, 4 miles southeast at 1,255 feet, is the lowest named place on the map yet plans for −35°F, on a 5 percent toe slope with some of the mildest bench ground on the map around it (−32°F). Otis, 6 miles north, plans for −38°F and reads 4°F colder than Merrill at bloom, the worst spring reading of any town on the map, and Grandfather Falls, where the Wisconsin drops 89 feet over bare Precambrian bedrock, plans for −38°F.

The Merrill station read −41°F in early February 1996, so plant with room. The −45°F trees have plenty: Haralson, Honeycrisp and Spartan apples, Toka plum and Evan's Bali tart cherry. The −40°F ones have 3°F: Zestar!® and Cortland apples, Summercrisp pear, Underwood plum and Meteor tart cherry. On the Pine River benches, Superior plum (−35°F) clears too. South toward Wausau, our Stevens Point, Wausau and Marshfield map takes over.

Antigo and the Antigo Flats

Antigo sits at about 1,500 feet on the Flats, with Spring Brook running through town. Moraines rim the Flats on the north and east, rising up to 250 feet above them, and under the plow there's a few feet of windblown silt over outwash sand and gravel: Antigo silt loam, well drained and Wisconsin's state soil since 1983.

The map puts Antigo along Spring Brook, 20 feet above the floor, at −34°F, MFTC 3b, with a typical winter of −22°F, about even with Merrill at bloom and the mildest of the towns here. Neva and Neva Corners, 5 to 7 miles north, plan for −34°F as well. Deerbrook, 6 miles north and just 10 feet above its floor, plans for −36°F and reads 3°F colder than Merrill at bloom. Kempster, 10 miles north and 70 feet above its floor, plans for −35°F.

That −34°F is colder than anything the two newer Antigo stations have recorded (−32°F in February 2021, −30°F at the county airport over 8 winters), but the old Antigo station read −38°F in early February 1996, so take the number at face value. The −40°F and −45°F trees have room to spare: Honeycrisp, Zestar!®, Wolf River and Sweet Sixteen apples, Luscious pear, Meteor, and Mount Royal plum. Superior plum and Lapins and Gold sweet cherries (−35°F) just clear it; give them a spot that drains. Grandview Orchard on County Road F sits on what it calls the county's second-highest point, and ground like that is where early bloomers belong.

Tomahawk, Lake Mohawksin and the Bradley flowages

Tomahawk grew up as The Forks, where the Tomahawk, Somo and Spirit rivers come into the Wisconsin; the Tomahawk Dam, a mile south of town, backs up Lake Mohawksin (1,437 feet). The map puts Tomahawk on the valley floor at 1,449 feet, planning for −38°F, MFTC 3a, with a typical winter of −26°F, 1°F colder than Merrill at bloom. There's almost no bench ground within 3 miles: the floor plans for −38°F, the coldest tenth −40°F, the warmest −37°F. West Kraft, 2 miles southwest in the river bottom, plans for −38°F; Gilbert, 3 miles south, −39°F; Bradley, 4 miles north, −36°F; Heafford Junction, on US 8 at the top of the map, −35°F.

USDA's 2023 map puts Tomahawk's ZIP in zone 4a, a half zone colder than Merrill and Antigo. With only 2°F of room for the −40°F trees, lean on the −45°F and −50°F ones: Wealthy and Norda apples, Haralson, Kerr applecrab, Bolshaya pear, Toka plum and FE tart cherry. Tomahawk Berry Farm on Roberts Road grows pick-your-own strawberries, and Honeoye (−50°F) is the one we'd plant here. Up the Hiawatha Trail toward Minocqua, our Rhinelander, Minocqua and Northwoods map picks up.

Gleason, Irma, Bloomville and the Prairie River hills

East of Merrill it's rolling country of reddish-brown Merrill till, cut by the Prairie River, which has run free since two dams came out in the 1990s; Gleason calls itself the Trout Fishing Capital of the World. Gleason, on WIS 17 at 1,464 feet, plans for −37°F, MFTC 3a, with a typical winter of −25°F, about even with Merrill at bloom. Bloomville, 2 miles southwest, plans for −38°F. Dudley, 2 miles northeast and only 10 feet above its floor, plans for −39°F and reads 3°F colder than Merrill at bloom, and Doering, in a river bottom 5 miles south, reads 3°F colder too.

Climb out and it flips. Bavaria, 6 miles east on a 5 percent slope 70 feet up, plans for −37°F but reads 4°F warmer at bloom. Kasper, 7 miles southeast and 80 feet up, plans for −36°F and reads 7°F warmer. Dutch Corners, on a bench 140 feet above the floor, plans for −35°F (3b) and reads 3°F warmer. Irma, on US 51 and 90 feet above its floor, plans for −37°F and reads 2°F warmer, and Chase Hill beside it reads 14°F warmer. On the floors around Dudley and Bloomville, plant like Tomahawk. On a slope like Bavaria's or Kasper's, try a Westcot or Morden 604 apricot (−45°F), and on ground as mild as Chase Hill's, a Lapins sweet cherry.

The Harrison Hills, Parrish and the moraines

The 1854 government surveyors called the southern town of Harrison very rough and uneven, with low wet swamps and many small lakes, and the Parrish moraine east of it runs as a broken, hummocky ridge from just south of Parrish toward Polar. Ground like that sorts cold hollow by hollow. Parrish, 10 feet above its floor at 1,601 feet, plans for −39°F, tied with Dudley for the coldest named place on the map, with a typical winter of −27°F. Harrison, 70 feet above its floor, plans for −37°F but reads 2°F colder than Merrill at bloom, and in hill country full of closed hollows the low spots hold the cold: the floor within 3 miles plans for −39°F and the benches −36°F. Bundy, 4 miles east, plans for −38°F, while Jeffris, next door on a 7 percent hillside 60 feet up, plans for −37°F and reads 4°F warmer at bloom because the cold drains past it. On the slopes, plant like Merrill; in the hollows and swamps, plant like Tomahawk.

Elcho, Pelican Lake, Summit Lake and the kettle country

In northern Langlade County the land climbs into the Northern Highland, and Elcho straddles the divide between the Wolf, bound for Lake Michigan, and the Pelican and Prairie, bound for the Wisconsin. Elcho, at 1,633 feet, plans for −38°F, MFTC 3a, with a typical winter of −26°F, 1°F colder than Merrill at bloom. The floor within 3 miles plans for −39°F and the bench ground −36°F, so getting up out of the bottoms buys about 3°F. Summit Lake, at 1,721 feet on a 5 percent toe slope 80 feet above its floor, plans for −37°F but reads 4°F warmer than Merrill at bloom, and Koepenick, 3 miles south, reads 2°F warmer.

Pelican Lake sits on the east shore of a 3,585-acre lake, 39 feet deep at most, and plans for −38°F, about even with Merrill at bloom; the lake freezes like the rest and does nothing for the winter number. Jennings and Lennox, about 5 miles east and 60 feet above their floors, read 4°F to 5°F warmer at bloom. At the map's edge, NOAA's North Pelican station holds the coldest reading anywhere around here, −48°F on February 1, 1996. With the −40°F trees only 1°F to 3°F clear up here, plant the −45°F and −50°F ones first and keep everything out of the bogs.

Spring frost and bloom around Merrill, Antigo and Tomahawk

Bloom-night frost follows the winter drainage, but in a thinner layer, so a slope that climbs out of it gets the whole benefit. Antigo, Tomahawk, Elcho, Gleason and Pelican Lake all read within 1°F of Merrill. The slopes run 4°F to 14°F warmer (Chase Hill, Kasper, Jennings, Jeffris, Bavaria, Summit Lake), and the bottoms 3°F to 4°F colder (Otis, Dudley, Deerbrook, Doering). NC State's fruit people point out that 3°F to 4°F can be the difference between no crop and a full one.

NOAA station records for 1991 to 2020 put the median last 32°F at May 17 in Merrill and May 18 at Antigo, and the last 28°F around May 4 and May 6. One spring in ten, the last 32°F comes June 1 or later at Merrill and May 27 or later at Antigo. The first fall 32°F comes around September 30 at both, for 136 and 134 frost-free days, and the old Antigo record had a killing frost as late as June 13. The University of Vermont treats fewer than 135 frost-free days as short-season country, so this map sits right on the line, and frost pockets shrink the season at both ends.

The Rice Reservoir station is the odd one: 3°F colder than Merrill in midwinter, yet the longest season on the map, 144 days, with its first fall 32°F not until about October 5. The National Weather Service in Burlington, Vermont, finds lakes do more to hold off the first fall freeze than the last spring one, and in early October the reservoirs are still open, which may be part of it. By January they're frozen and give nothing back.

The late spring is also a shield. In the May 14 and 15, 2016 frost, Wisconsin apple and grape losses ran up to 95 percent, but the north fared better because its flower buds had only begun to break. Open blossoms of apple, pear, cherry, peach, apricot and plum all start dying near 28°F. Apples have the most room, since only about 15 percent of the blossoms need to set for a crop. Wide-open honeyberry (haskap) flowers take 19°F, and at our place in 2026 Red Lake currant and Montana Black Currant fruited well after their flower buds saw about 22°F. Put the early bloomers (apricots, plums, sweet cherries) highest, on a slope with somewhere for the cold to go; a north slope holds them back, and an east slope that warms quickly on a frosty morning is ideal (Bob Purvis's rules). A hedge, fence line or road fill across a slope backs cold up into the trees above it, so open a gap at the low end. Through bloom, mow short, don't till, and water a day or two before a frost night.

What the weather records say

The coldest readings in NOAA's station records here: −48°F at North Pelican on February 1, 1996; −45°F at Tomahawk Spirit Reservoir on January 18, 1967; −42°F at Merrill (February 5, 1907, and January 12, 1912) and Koepenick (January 7, 1912); and −39°F at Antigo on January 18, 1967. The most recent big outbreak, in February 2021, brought −34°F at Rice Reservoir but only −25°F at Merrill.

Over the long records the year's coldest night averages −26°F at Merrill and −25°F at Antigo. NOAA station records show the worst night in about 30 winters runs a median 13°F below a station's average winter low, and that's the kind of bad night the planning low is built around. USDA's 2023 map, built on the average, puts Merrill (54452), Antigo (54409), Gleason, Irma and Elcho in zone 4b (−25°F to −20°F) and Tomahawk (54487) in 4a (−30°F to −25°F). Our typical winters land in about the same zones (−24°F at Merrill, −26°F at Tomahawk); our MFTC zones run 3a and 3b because they're built on the bad night. Marathon County Extension's Janell Wehr advises leaning on zone 4 or even zone 3 plants since the 2023 map came out, and treating zone 5 plants as experiments.

What you can grow around Merrill, Antigo and Tomahawk

Every pick below has come through the planning low for its ground; "worth a try" means within 5°F, on your best spot.

• The Antigo Flats, the Pine River benches and the warm slopes, −32°F to −35°F (Antigo, Neva, Pine River, Dutch Corners, Chase Hill): Honeycrisp, Wolf River, Zestar!® and Sweet Sixteen apples; Luscious pear; Superior and Mount Royal plums; Meteor tart cherry; Westcot apricot (it'll live; the crop depends on bloom nights); Lapins and Gold sweet cherries on a slope that reads warm at bloom; Valiant grape. Worth a try on the −32°F benches: Montmorency tart cherry and Stanley plum (−30°F).
• Merrill and most of the farm and lake country, −36°F to −38°F (Merrill, Tomahawk, Gleason, Irma, Kasper, Deerbrook, Elcho, Summit Lake, Pelican Lake, Harrison, Bradley): Haralson, Snowsweet®, Spartan and Lodi apples (−45°F), Cortland (−40°F); Vekovaya and Ure pears; Toka, Underwood and Pipestone plums; Evan's Bali tart cherry; Dolgo crabapple; Morden 604 apricot on a slope. Worth a try: Superior plum and Lapins (−35°F).
• Parrish, Dudley, Gilbert and the coldest bottoms around Tomahawk, −39°F to −40°F: Wealthy, Norda and Frostbite apples; Kerr, Centennial and Trailman applecrabs; Bolshaya pear; Brookred plum; FE tart cherry; Romeo and Juliet dwarf cherries; Debbie's Gold apricot. The −40°F trees sit right at the line.
• Bush fruit, anywhere: Honeyberry, Montana Black Currant, Nanking Cherry, Success serviceberry and Honeoye strawberry (−50°F); Red Lake currant, Pixwell gooseberry and Boyne raspberry (−40°F, right at the line in the coldest bottoms).

UW Extension's northern Wisconsin list says to skip peaches, sweet cherries, Japanese plums and apricots. Siberian C peach (−35°F) should live on the Flats, but it ripens very late, and at 134 frost-free days we wouldn't count on fruit. In the cold bottoms, if you only plant one tree, make it Kerr or Trailman. UW names Toka as the pollenizer for Underwood, Pipestone and Superior plums, while Mount Royal and Stanley set fruit on their own. Apples and pears want a second variety nearby, and our pollination maps show what pairs with what.

For rootstocks, UW recommends M.26, M.7 and Bud.9, and UW Extension's Jason Fischbach adds G.30 and M.111 for northern Wisconsin. Roots are the weak link and snow saves them: at Ed Schultz's farm, Bud 118 rootstock has seen near −50°F under snow with no damage. In a thin snow year, mulch the root zone and keep the soil moist into winter. In muck and peat ground, test drainage first (dig 2 feet, fill, let drain, refill; under 10 hours is well drained). Taper water from mid-August so trees harden off, paint trunks with white latex diluted 50 percent against sunscald, fence for deer, and guard trunks from rabbits and mice.

Fruit history here

This has always been potato country first, but the 1947 Langlade County soil survey found fruits and berries on most Langlade farms, especially in the hilly part of the county. Wolf River, one of Wisconsin's own apples, was found along the Wolf River in 1875, and we sell it, along with Northwest Greening (−40°F), which started from a seed planted near Iola in 1849. Helene's Hilltop Orchard in Merrill was a dairy and pumpkin farm from 1919 until Dave and Helene Pagoria planted apples in 1979, and today it grows Zestar, Honeycrisp, McIntosh, RiverBelle and Cortland on dwarf trees.

Questions people ask

What growing zone is Merrill, WI?

Merrill plans for −37°F, MFTC zone 3a, with a typical winter of −24°F. USDA's 2023 map puts Merrill's ZIP, 54452, in zone 4b (−25°F to −20°F). USDA's zone is based on an average winter and ours on the bad night we plan for, so we'd plant trees that have come through −40°F.

What zone is Antigo, WI?

Antigo plans for −34°F, MFTC zone 3b, with a typical winter of −22°F, the mildest of the towns on this map. USDA's 2023 map puts Antigo's ZIP, 54409, in zone 4b. The old Antigo station has read −39°F, so the −40°F trees are the safe picks.

When is the last frost in Antigo and Merrill?

NOAA station records for 1991 to 2020 put the median last 32°F at May 18 in Antigo and May 17 in Merrill, with the last 28°F around May 6 and May 4. One spring in ten it comes as late as May 27 at Antigo and June 1 at Merrill. Frost pockets and bogs run later.

Why is Merrill colder than Antigo?

Merrill sits in the Wisconsin River valley where the Prairie River comes in, and on clear, calm nights cold air drains off the surrounding hills and pools in the bottom. Antigo sits about 270 feet higher on the Antigo Flats, a broad, level outwash plain with no deep trough to collect cold. Over 65 years of NOAA records Merrill has run a median 3°F colder.

Can you grow apples in Tomahawk, WI?

Yes, the hardiest ones. Tomahawk plans for −38°F, MFTC zone 3a, with a typical winter of −26°F, and USDA's 2023 map puts it in 4a. Wealthy and Norda (−50°F) and Haralson and Frostbite (−45°F) have room; the −40°F apples have just 2°F to spare, so give them your highest ground.

Can you grow peaches in northern Wisconsin?

Not reliably. UW Extension advises against peaches for northern Wisconsin, and the frost-free season on this map runs only 134 to 144 days. Siberian C, the hardiest peach we know of, has come through −35°F, enough for Antigo's −34°F, but it ripens very late. Apples, plums and tart cherries are the better bet.

Warmer spots, colder spots

Here's the number to plan for at named places on the map, warmest first. Each one is the 1-in-30-year low for that spot: the cold hardiness calculator's number from the same weather stations, sharpened by our microclimate model for the ground right there. Zone is our MFTC zone, set by that one bad night, not by an average.

The weather stations behind it

These are the long-record stations in and around this map, with each one's own numbers since the winter of 1995-96. The last column is this map's 30-year number right at the station, which won't match the station exactly: it's a blend of the stations around it, the way the calculator works everywhere.

Source: NOAA records through ACIS, winters 1995-96 through 2025-26. What the "carried forward," "gaps filled" and AWOS rows mean is explained in how our microclimate maps work.