Plant: tree; to 10 m high, sparsely to densely pubescent on young growth and lower leaf surfaces, usually dioecious; young twigs glabrous to densely pubescent, often more or less glaucous, the epidermis smooth, greenish or reddish, the older twigs more or less rough, gray; buds covered by two reddish, tan, or yellowish valvate scales, these sparsely to densely hairy, the pubescent inner scales greatly elongating as the bud opens Leaves: mainly 3-foliolate, occasionally 3-lobed, 3.5-13.5 cm long, 3.5-18 cm wide, concolorous, the terminal leaflet up to 11 cm long by 8 cm wide, the lateral leaflets up to 9 cm long by 6 cm wide; apex of leaflets acute to acuminate; base of leaflets rounded to cuneate, sometimes oblique in lateral leaflets, sometimes acuminate in terminal leaflets; petiole 2-7.5 cm long, green or reddish; margin of leaflets coarsely toothed or lobed, the teeth acuminate to obtuse INFLORESCENCE: inflorescences many flowered, the staminate umbel-like, the pistillate racemose Flowers: ca. 5 mm long, less than 1 mm wide at base of perianth, the perianth greenish-yellow, with ca. 4 subelliptic segments ca. 0.2-2 mm long, the receptacle blending with filiform pedicel; pedicels 1-4 cm long Fruit: samaras 2.3-3.6 cm long, the wing 0.7-1.4 cm wide, the infructescences up to 15 cm long Misc: Riparian habitats and other wet wooded areas; 900-2750 m (3000-9100 ft); Mar-Jun (retaining fruits until about Oct) REFERENCES: Landrum, Leslie R. 1995. Aceraceae. J. Ariz. - Nev. Acad. Sci. 29(1): 2, 2-3.
Tree to 20 m tall, trunk to 1.2 m in diameter Leaves: opposite, pinnately compound, stalked, 5 - 12 cm long, 3.2 - 7 cm wide, with three to five leaflets. Flowers: either male or female, found on separate trees (dioecious), borne in clusters, greenish yellow, 3.5 - 4.5 cm long. Fruit: winged (samara), paired, 3.5 - 4.5 cm long, wings narrowly angled (less than 45 degrees). Bark: gray to light brown, becoming deeply furrowed with rounded ridges. Young twigs: green to reddish brown, usually covered with a whitish waxy coating that is easily rubbed off (glaucous). Leaf scars: wrap around the twig and meet to form a sharp point. Leaflets: light green, elliptic, margin usually coarsely toothed but may be shallowly lobed or non-toothed.
Similar species: Seedlings may be mistaken for Toxicodendron radicans (poison ivy). Toxicodendron radicans has alternate leaves with only three leaflets per leaf. Leaves also resemble those of Fraxinus sp. (ash), but Fraxinus species lack paired fruit and green to purplish twigs usually covered in a waxy coating. Acer negundo var. violaceum has purple to violet twigs always covered in a waxy whitish coating.
Flowering: late March to early May
Habitat and ecology: Very common and often weedy species in the Chicago Region, occurring in moist woods, flood plains, disturbed areas, and along riverbanks.
Occurence in the Chicago region: native
Notes: Acer negundo was once used as a street tree because it adapts to many soils. It is no longer planted due to its weak wood, pest and disease problems, and messy fruit.
Etymology: Acer is derived from a Latin word meaning sharp, which refers to the hardness of the wood. Negundo comes from the Sanskrit name for Vitex negundo, which has leaves resembling those of A. negundo.
Author: The Morton Arboretum
From Flora of Indiana (1940) by Charles C. Deam
Usually infrequent. In low ground along streams and rarely far from them on higher ground in woods and along fences and roadsides. In some of the low woods along streams in the southwestern part of the state this species is common, and a nuisance as a forest tree because of its inferior quality.
Indiana Coefficient of Conservatism: C = 1
Wetland Indicator Status: FAC
Diagnostic Traits: Leaves compound, leaflets mostly 3-7. Indiana populations are classified as var. negundo. Other varieites occur in some Plains States and westward.
Deam (1932): This species on account of its rapid growth was formerly much used as a shade tree. It is believed that most of the trees now found along roadsides, fences, clearings and on the drier banks of streams are from seed distributed by the wind from planted trees. This species is now little used as a shade tree and is never recommened because it sheds its leaves early, and is subject to injury from disease and insects.
Welsh et al. 1993, Martin and Hutchins 1980, Landrum 1995
Common Name: boxelder Duration: Perennial Nativity: Native Lifeform: Tree Wetland Status: FACW General: Dioecious trees or rarely small shrub, usually 4-12 m tall, with velvety to hairy branchlets. Leaves: Usually trifoliate, rarely with more leaflets in a compound leaf, leaflets 2-10 cm long and 12-25 mm wide, usually coarsely toothed or lobed, hairy to glabrous on both surfaces, especially along veins. Flowers: Drooping on very long pedicels, staminate in fascicled subumbellate clusters, pistillate in drooping racemes; sepals 4-5, very small, usually 1-2 mm long, petals lacking, ovary glabrous or hairy. Fruits: Samaras usually glabrous with wings descending-spreading, 2-5 cm long. Ecology: Found in moist soils from 3,000-7,500 ft (914-2286 m); flowers April-May. Distribution: Ranges across North America into Canada and south to Guatemala. Notes: This species is distinguished best by the trifoliate leaves with the typical boxelder notches on either side of the leaf. Ethnobotany: Taken as an emetic, inner bark and sap boiled until it crystallized into sugar, wood used for bowls and utensils, fuel, musical instruments, pipe stems, and a variety of ceremonial uses. Etymology: Acer is the classical Latin name for the maple genus, while negundo is from Sanskrit nirgundi, which is the name of a plant that has similar leaves to elder. Synonyms: None Editor: SBuckley, 2010
Tree to 20 m, the trunk soon deliquescent; lfls 3-5 or on rapidly growing shoots to 9, pinnate, lanceolate to ovate or oblong, coarsely and irregularly serrate or with a few shallow lobes; dioecious; fls apetalous, appearing with or before the lvs, the staminate in sessile, umbel-like fascicles, drooping on slender pedicels, the pistillate in drooping racemes; disk wanting; mericarps 3-4.5 cm; 2n=26. Moist, especially alluvial soil; N.H. to Fla., w. to the Pacific, and irregularly in Mex. and Guat. Var. negundo, the common e. Amer. var., has glabrous, often glaucous twigs. (Negundo n.; N. nuttallii) Var. interius (Britton) Sarg. (Negundo i.), with velutinous twigs and usually with tufts of hairs in the vein-axils beneath, is chiefly western, occasionally extending to Minn. and Mo. Var. texanum Pax, with similarly hairy twigs, rather densely puberulent frs, and short-acuminate lfls pubescent over the whole lower surface, occurs chiefly from the Ozarks to Tex., extending e. to s. Ind.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.