northern hackberry

not listed

N5? - Secure

SNR - Unranked

not listed

FACU - Facultative upland

FAC - Facultative

FAC - Facultative

Northern hackberry is a medium to large, moderately fast-growing, deciduous tree. In Minnesota mature trees are usually 40′ to 60′ tall and 10″ in 16″ in diameter at breast height. Large individuals can reach up to 75′ in height and 56″ in diameter. It is moderately long-lived, often reaching between 150 and 200 years in age. It has a deep, fibrous root system that, where conditions permit, may be10 to 20 feet deep. It has no taproot. It is usually found as scattered individuals in river terraces and floodplains, but it can persist when planted (by humans or birds) in dry upland areas.

The trunk is slender and usually divided near the base of the crown into a few large, upright, spreading limbs. On older trees the trunk is significantly flared at the base where it joins the surface roots. The branches are gracefully spreading and sometimes slightly drooping at the ends. Young trees have an oval crown. Older trees have a spreading, irregularly rounded crown.

The bark on young trees is thin, smooth, and light grayish-brown. It soon develops warty raised knobs, which develop into narrow, vertical, wavy, corky ridges as the tree ages. The wing-like ridges on otherwise smooth bark is a unique identifying feature of this tree. As the tree matures the ridges become flattened and more closely spaced and the bark becomes scaly.

First-year twigs are slender, slightly zigzagged, green becoming tinged with brown, and usually hairy. Second-year twigs are brown and hairless. Leaf scars are U-shaped to semicircular and have three dot-like bundle scars. The pith is white and is finely chambered, at least at the leaf nodes.

Lateral buds are reddish-brown, egg-shaped, flattened, pointed, ¼″ to 5 ⁄16″ long, and closely appressed to the twig. There is no true terminal bud, but the lateral bud at the end of the twig is often bent sideways.

The leaves are deciduous, alternate, and unlobed. They and are attached to the twig on a slender, hairy, ¼″ to ⅝″ long leaf stalk. The blades are leathery, egg-shaped to lance-shaped, 2⅜″ to 4¾″ long, and 13 ⁄16″ to 2¼″ wide. They taper gradually to a long, drawn out point at the tip with concave sides along the tip. The base is asymmetrical, rounded or somewhat heart-shaped. The upper surface is dark green and may be either mostly hairless or covered with short, straight hairs. The lower surface is pale green and hairy along the veins. The margins are toothed from the tip to well below the middle but not near the base. There are 10 to 40 sharp, forward pointing teeth per side. There are three main veins, one midrib and a pair of veins that originate just below the base of the blade, and 4 or 5 lateral veins per side that originate at at intervals along the midrib. The leaves turn light yellow in the fall.

Flowers appear in late April to late May. Male and female flowers are borne on the same first-year brachlet of the same tree. Male flowers appear on 1 ⁄16″ to ¼″ long stalks in small clusters at the base of the twig. Each male flower has 4 or 5 greenish or yellowish sepals, no petals, and 5 or 6 stamens on white filaments. Female flowers appear on ⅛″ to ⅜″ long stalks singly or in pairs in a leaf axil of the twig. Each female flower has 4 or 5 greenish or yellowish sepals, no petals, and 2 stigmas that are bent backward. The flowers are pollinated by the wind

The fruit is a fleshy, relatively dry drupe with a single pitted stone. It is spherical, ¼″ to ½″ in diameter, and is tipped with the remnants of the style. It is green at first, turning dull reddish-purple and often wrinkled at maturity. It matures in August to late September and remains on the tree until eaten by a bird.

40′ to 60′

The champion northern hackberry in Minnesota is on private property near Janesville, in Waseca County. In 2018 it was measured at 84′ tall and 173″ in circumference (55″ in diameter), with a crown spread of 50′.

Green

Moist; river terraces, floodplains; moderately shade tolerant when young.

Late April to late May

hackberry nipple gall maker (Pachypsylla celtidismamma)

hackberry witches’ broom mite (Eriophes celtis)

Sources

2, 3, 4, 5, 7, 28, 29, 30.

Native

Common

The genus Celtis was formerly placed in the family Ulmus (elms). A molecular phylogenetic study in 2002 caused a reordering of families in the order Rosales. As a result, this genus is now grouped with hemp and hops in the family Cannabaceae. The leading sources for taxonomic ranking, including ITIS, NCBI, GRIN, and The Plant List reflect this change. Most botanical sources, including PLANTS and Flora of North America (FNA), do not.

Fruit of a northern hackberry, Freeborn County, MN, July 2017

Northern hackberry, Freeborn County, MN, July 2017. They can get quite large

Young northern hackberry

Middle aged northern hackberry

Older northern hackberry

Northern hackberry trunk

Open grown northern hackberry, showing strong branching form, Freeborn County, MN, December 2016. Makes a splendid shade tree.

Location: Freeborn County, MN

They can get quite large

Location: Freeborn County, MN

Middle aged northern hackberry