The Arrowhead region of Minnesota, known as the Northern Superior Uplands subsection, includes all or parts of Carlton, Cook, Itasca, Koochiching, Lake, and St. Louis counties.

This area is characterized by bedrock terrain peppered with many lakes and thin deposits of coarse loamy soil. The region receives more of its precipitation as snow than any section in the state, has the longest period of snow cover, and has the shortest growing season.

Forests with red and white pine were widespread in the past, mixed with aspen, paper birch, spruce, and balsam fir. Much of the pine was cut in the late 1800s and early 1900s, leaving forests dominated mostly by aspen and paper birch. Jack pine forests are present on droughty ridges and bedrock exposures, as well as on local sandy outwash deposits. The highlands along Lake Superior have a local climate moderated by the lake that favors forests dominated by sugar maple with some white pine, yellow birch and northern white cedar.

The following species are not currently native to Ecoregion 2, but this region's future climate may be suitable  to support habitat for these species. Extension Forestry is interested in learning more about these species, and we want to know if any of these species are already present on the landscape in Region 2. Learn more about each species using the drop-down buttons below.

Image credit: Anna Stockstad, UMN Extension

American hornbeam is medium sized understory tree, native to much of eastern MN but considered migration potential to ecoregions 1 and 2. This tree is sometimes called musclewood because the smooth-barked trunk looks like the ripped muscles of an elite runner. It's considered hardy from plant zones 3a - 9b. It produces noticeable catkins in early summer and very small nuts in late summer. To learn more about this tree visit the NC State Extension Horticultural page.

Photo from iNat viola2020

Bitternut hickory, a tall broadleaf tree , native to southeastern quarter of Minnesota and small packets of northern Minnesota but considered migration potential for ecoregions 1, 2 and 10.  Its name was inspired by the inedible nuts and it has alternate, pinnately compound leaves with 7 -9 leaflets. The  bright yellow buds are a distinguishing characteristic. It's considered hard from plant zones 4-9.  To learn more about identification visit the UMN website and the NC State Extension Horticulture page.

Photo leaf and bud by Paul Wray & Chris Evans, Bugwood.org

Shagbark hickory is native to the central and eastern United States, and can be found growing in southeastern Minnesota. This species is considered migration potential for ecoregions 1, 2, 3, 4, 6, and 10. Like other hickories, it's a large broadleaf tree with alternate, pinnately compound leaves with 5-7 leaflets. It can be distinguished from other hickories by its mature bark, which is shaggy, light gray, and separating into thick vertical strips that seem to be sloughing off the trunk. Learn more about shagbark hickory, visit the UMN website and the NC State Extension Horticulture page.

Photo by Rob Routledge, Sault College, Bugwood.org

This small understory tree that has conspicuous small purple flowers along the stem in early spring. It's considered hardy from plant zones 4a-9b. To learn more about this species and how to identify it visit the NC State Extension Horticulture page or the University of Wisconsin-Madison Extension website. This tree is not considered native to Minnesota and is planted in some communities including Rochester and the Twin Cities.

Photo by Paul Wray, Iowa State University, Bugwood.org 

White ash is native to the eastern U.S. and can be found in southeastern Minnesota. Like other species of ash, it has opposite, pinnately compound leaves with five to nine leaflets.  The leaflets are clearly stalked and can be differentiated from green ash (short stalks) and black ash (sessile/no stalk) by the longer stalks on white ash leaflets. It can also be distinguished from black ash and green ash using the buds, which are rounder and shorter than the buds of black ash and green ash (both of which are more pointed and may resemble Hershey's Kisses). Learn more about white ash on the UMN website, and hone your ash identification skills using this resource from University of Wisconsin-Green Bay.

Forest health threat: Please be aware that emerald ash borer (EAB) kills white ash, in addition to the rest of Minnesota's ash species.

Photo by Joseph OBrien, USDA Forest Service, Bugwood.org

Honeylocust is a large deciduous tree with alternate and compound leaves that have many small, round leaflets. Wild-grown honeylocust trees have large thorns, while other varieties lack the thorns. A member of the legume family, honeylocusts have long seed pods. Honeylocust is native to the central U.S. and the northern end of its range extends into Iowa. It's hardy to zones 3-8. Learn more about honeylocust on the UMN website and the NC State Extension Horticulture page.

Photo by Franklin Bonner, USFS (ret.), Bugwood.org

Black walnut is a medium to large overstory tree with leaves that are alternate and compound, with 15-20 long and narrow leaflets. The fruit is green and fleshy, with an edible nut inside. The wood of black walnut is extremely valuable for wood products, including furniture, lumber, and paneling. Black walnut is native in southeast Minnesota, and is hardy to zones 4-9. Learn more about black walnut on the UMN website.

Photo from Rebeckah D. Wallace, University of Georgia, Bugwood.org

Eastern redcedar is a coniferous tree with thin, peeling bark and two different forms of needles. Most needles are dark green and scaled (somewhat similar to northern white cedar), while other needles sharp and awl-shaped (more similar looking to hemlock or spruce needles). It produces a blue berry-like cone that is preferred by birds during the winter. Eastern redcedar is hardy to zones 2-9 and is native to southern Minnesota. Eastern redcedar may become invasive near native grasslands. Learn more about eastern redcedar on the UMN website.

Photo by Joh Ruter, University of Georgia, Bugwood.org

Eastern cottonwood is a large, dominant canopy tree planted in urban areas and found naturally in moist, well drained sites and along riverbeds. Large trees are preferred nesting places for bald eagles. Cottonwood is native to southern Minnesota but considered migration potential to ecoregions 1, 2 & 10 along the Canadian border. It's considered hardy for plant zones 2 - 9. Cottonwood's almost triangular shaped, simple, alternate leaves are fairly easy to identify.  To learn more about this species visit the UMN website and the NC State Extension Horticultural page.

Photo by Paul Wray, Iowa State University, Bugwood.org 

White oak is a long-lived overstory tree that is native to most of the eastern U.S., and the northern end of its range extends into east-central MN. White oak prefers moist, nutrient-rich sites and its acorns are an important food source for many wildlife species. A member of the white oak group, this tree has round lobes that are deeply divided. White oak is hardy to zones 3 through 9. Learn more about white oak on the UMN website.

Forest health threat: White oak is susceptible to oak wilt, a fungal pathogen that kills oaks. Oak wilt kills white white oaks are less quickly than red oaks (such as northern red oak and northern pin oak).

Photo by Chris Evans, University of Illinois, Bugwood.org

Swamp white oak is a large overstory tree that is native to southeast MN and much of the eastern and central U.S.  As a member of the white oak group, swamp white oak has rounded lobes, but not nearly as deeply divided as white oak. Some of the leaves on swamp white oak can resemble a diamond in shape. The undersides of swamp white oaks are light green and slightly hairy. Swamp white oak is hardy to zones 3-8. Learn more about swamp white oak on the UMN website.

Forest health threat: Swamp white oak is susceptible to oak wilt, a fungal pathogen that kills oaks. Oak wilt kills white white oaks are less quickly than red oaks (such as northern red oak and northern pin oak).

Photo by Paul Wray, Iowa State University, Bugwood.org

In the red oak group, black oak is a large overstory tree that looks similar to northern red oak. The acorns on black oak are elliptical in shape, and the leaves have 7-9 shallow or deep lobes. Acorns are an important food sources for many wildlife species. Black oak is native to the southeast corner of MN, and is hardy to zones 3-9. Learn more about black oak on the UMN website.

Forest health threat: Black oak is very susceptible to oak wilt, a fungal pathogen that kills oaks. Oak wilt kills red oaks more rapidly than white oaks. 

Photo by Chris Evans, University of Illinois, Bugwood.org.

Scarlet oak is a tree in the red oak group that produces brilliant bright red foliage. The leaves have 7-9 lobes that re deeply divided and C-shaped. Scarlet oak is a relatively fast-growing oak and its acorns are eaten by many species of wildlife, like other oak species. The acorn of scarlet oak has a deep bowl-like, shiny, scaly cap. Scarlet oak is hardy to zones 4-9. Learn more about scarlet oak on the NC State Extension Horticulture page.

Forest health threat: Scarlet oak is very susceptible to oak wilt, a fungal pathogen that kills oaks. Oak wilt kills red oaks more rapidly than white oaks. 

Photo by Franklin Bonner, USFS (ret.), Bugwood.org

Chinkapin oak is a tree is the white oak group, but its leaves look chestnut-like in appearance. The leaves are diamond-shaped and are toothed with shallow lobes. Chinkapin oak is native across the eastern U.S., including the far southeast corner of MN. It's considered hardy to zones 3-7. Learn more about chinkapin oak on the NC State Extension Horticulture page.

Forest health threat: Chinkapin oak is susceptible to oak wilt, a fungal pathogen that kills oaks. Oak wilt kills white white oaks are less quickly than red oaks (such as northern red oak and northern pin oak).

Photo by Paul Wray, Iowa State University, Bugwood.org

Unlike Minnesota oak species, live oak is a long-lived evergreen tree that develops a wide crown. The leaves are glossy and oblong with no lobes like other oaks. The acorns are egg-shaped and often black in color. Live oak is native far from Minnesota along the coastal plains of Virginia, North Carolina and along the Gulf Coast. Live oak is hardy to zones 8-10. Learn more about live oak on the NC State Extension Horticulture page.

Photo by Franklin Bonner, USFS (ret.), Bugwood.org

Eastern hemlock is a large, dominant canopy conifer tree native to small pockets of Minnesota. It's listed by MN DNR as endangered so cannot be taken, imported, transported or sold. It has small cones and small flat needles and dark brown-gray, fissured or ridge bark. It's considered hard from plant zones 3a-7b. Hemlock wood adelgid has killed many hemlock trees southeast of MN. To learn more about identification visit the UMN website and the NC State Extension Horticulture page.

Photo by Bill Cook, Michigan State University, Bugwood.org 

This small to medium-size tree has scaly gray bark with reddish-brown stems and simple, alternate leaves with margins that are double serrate. It has been recommended for planting in Minnesota and is considered hardy from plant zone 4-7. To learn more about this species and how to identify it visit the NC State Extension Horticulture page or the UMN website. Below it is paired with yellow birch to help differentiate between the two birch species. 

Photo from iNat by newenglandtrees.

Hackberry is a very common urban tree and can be found growing along river terraces and floodplains in southern and central Minnesota. Its range covers much of the central and eastern U.S. Th leaves are alternate and simple, and the twigs grow in a zig-zag pattern. The fruit looks like small, dark berries (drupes). The bark is easily distinguishable due to its warty appearance. Hackberry is hardy to zones 2-9. Learn more about hackberry on the UMN website.

Photo by Paul Wray, Iowa State University, Bugwood.org

American beech is a large, long-lived overstory tree with characteristic gray bark that remains smooth into maturity. American beech can be found growing along ravines and valleys, and the northern end of its native range extends into Illinois. It can be found as far south as Florida. The nuts are a preferred food for many wildlife species and its large crown provides habitat for many species of mammals and birds. American beech is hardy to zones 3-9. Learn more about American beech on the UMN website.

Forest health threat: Beech bark disease kills American beech due to the combination of the introduced beech scale insect and several fungal species. Beech bark disease has been detected as far west as eastern Wisconsin.

Photo by Rob Routledge, Sault College, Bugwood.org

Sweetgum is a large deciduous tree with star-shaped leaves and large spiky fruits known as gumballs. In the fall, the leaves turn bright red, purple, yellow or orange. The tree produced a resinous gum underneath the bark that can be used for chewing gum, incense, and medicines. Sweetgum is hardy to zone 5-9 and is native to the southeastern part of the U.S. Learn more about sweetgum on the NC Extension Horticulture page.

Photo by Forest and Kim Starr, Starr Environmental, Bugwood.org

Bigleaf magnolia has the largest simple leaf and largest flower of any tree native to North America. This tree is rare in the wild, but cultivars are sold. Green leaves above and silver below can be up to 3 feet long and 1 foot wide. Fragrant, showy white flowers are 8-14 inches across. It is considered hardy from plant zone 5a-8b. To learn more about this species and how to identify it visit the NC State Extension Horticulture page. Information about cultivars can be found at the UMN website.

Photo from iNat by zanegreen.

In the elm family, cedar elm has smaller leaves than American elm that are thick and oblong.  The thick leaves have a scale-like texture and are evergreen in its southern range. Native to Texas and parts of Louisiana and Arkansas, cedar elm is hardy to zones 6-9. Learn more about cedar elm on the Lady Bird Johnson Wildflower Center page.

Forest health threat: Like other elms, cedar elm is susceptible to Dutch elm disease.

Photo by Charmaine Richardson, Wildflower Center Digital Library

Ashe juniper  a conifer native to Texas and parts of Arkansas and is hardy to zones 6-9.  The needles are scale-like, and the tree produces green berry-like seed cones. This species can be found growing in thickets in its native range due to its multi-stemmed growth form. Learn more about ash juniper on the Lady Bird Johnson Wildflower Center page.

Photo by Joseph A. Marcus, Wildflower Center Digital Library