LA Urban Forest Program

A medium sized tree with ashy to dark brown bark, young parts pubescent. Leaves petiolate, petiole 2.5-5 cm long, lamina 7.0-18 cm long, rather longer than broad, 9-11 nerved, cleft about halfway down into 2 acute or rounded lobes, minutely pubescent below when young. Inflorescence few flowered panicles at the ends of the branches. Flowers pedicellate, pedicel c. 5-13 mm long; tomentose, bract c. 3 mm long, bracteole c. 2 mm long. Hypanthium 7-10 mm long. Calyx c. 2.5-3.0 cm long, usually splitting into two reflexed segments, one emarginate the other 3 toothed. Petals 3.7-5 cm long, oblanceolate, long clawed, spreading, veined. Stamens usually 3 fertile, others reduced to antherless filaments. Ovary downy, long stalked; style long, stigma oblique. Pod 15-25 cm long, c. 1.5-2 cm broad; stalk c. 2 cm long. Seeds 12-15, almost round, c. 1.2-1.3 cm in diameter, brown, smooth. less ↑

General: Heath family (Ericaceae). Pacific madrone is an evergreen tree that is native to the northwestern Coast Ranges of North America. The trees have single or multiple trunks with rounded, spreading crowns. Mature trees reach heights of 6m to 30m or more depending on environmental conditions. The alternately arranged leaves are oval, (7 to 15 cm long), thick, and have finely serrated margins. The leaf surfaces are glossy dark green above with lighter grayish green beneath. Leaves remain on the plant for two years before they are shed. The striking cinnamon red bark is thin and smooth. The bark on young branches peels in large papery flakes to reveal an attractive, satiny green surface beneath that darkens with time to deep red. In midsummer, the exfoliated bark, along with shed leaves in shades of red to orange, form a lovely colorful carpet beneath the tree canopy (Saunders 1923). Fragrant bell-shaped flowers appear in large, showy clusters at the ends of the branches during the spring, from March through May, but sometimes as early as January. The flowers (8mm) are yellowish-white to pink and consist of 5 fused petals. The fruits are loose clusters of bumpy, scarlet red berries (8 to 12mm) that contain a mealy pulp and about 20 hard seeds. The genus was named from the Celtic word “arboise,” which means rough fruit (Young & Young 1992). The early Spanish Californians named the tree “madroño” after the strawberry tree (Arbutus unido), which grows in Spain and other nearby Mediterranean countries (Parsons 1966). The edible fruits ripen from the early fall until December or January.

Distribution: Pacific madrone is native to the West Coast of North America and occurs from the Southern Coast Ranges of California to British Columbia in the north from 100 to 1500 m. Occasional populations are found in the Sierra Nevada Range at middle elevations. For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site.

Habitat: Pacific madrone is found on wooded slopes and canyons in oak, redwood, and mixed evergreen forests as well as in chaparral communities. The trees are commonly associated with other species and rarely occur in pure stands. less ↑

Trees to 50 m tall; trunk to 1.5 m d.b.h.; trunk straight; bark dark gray, flaking; crown tower-shaped; branchlets spreading horizontally or drooping; lateral branchlets usually pinnately arranged, drooping. Leaves dimorphic: those of young trees and lateral branchlets loosely arranged, spreading openly, bright green, glaucous abaxially, subulate, usually laterally depressed, upcurved, 6-12 mm, 3- or 4-ridged; those of mature trees and cone-bearing branchlets densely arranged, slightly openly spreading, broadly ovate or triangular-ovate, ± curved, 5-9 mm, widest at base, midvein obviously raised or not, apex obtuse. Pollen cones terminal, solitary. Seed cones subglobose, 8-12 × 7-11 cm, sometimes wider than long; apex of bracts triangular, flattened, acute, upcurved. Seeds ellipsoid, slightly flattened, with a lateral wing. less ↑

Angophora costata grows into a large tree (although it is often stunted or mallee-like) and is characterised by a distinctive orange or pink hue to trunk when bark has been newly shed. The colour fades with time and is a more subdued greyish hue in winter. White flowers occur in summer. less ↑

• Plant: small deciduous tree that grows 10-50 ft. in height and often has multiple trunks; the bark is light brown, nearly smooth, thin and has lens-shaped spots along the stem.
• Leaves: alternate, twice-pinnately compound, fern-like.
• Flowers, fruits and seeds: flowers are pink, fragrant and look like pom-poms; flowering occurs in early summer; fruits are flat 6 in. long seedpods that develop in the late summer.
• Spreads: by seed and vegetative growth.
• Look-alikes: honey locust (Gleditsia triacanthos) and black locust (Robinia pseudoacacia) with leaves that are once-pinnately compound.
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General: Maple Family (Aceraceae): Boxelder is a native tree growing to 20 m tall, with broad rounded crown, usually developing a shallow, fibrous root system; bark light gray-brown with shallow fissures, becoming deeply furrowed; twigs slender, shiny green, usually glabrous but sometimes hairy. The leaves are opposite, 13-20 cm long, pinnately compound with 3(-5 or more) leaflets 5-10 cm long and 3-6 cm wide, long-pointed, coarsely toothed and often shallowly lobed. The flowers are yellow-green, about 5 mm long, the male (staminate) flowers fascicled, the female (pistillate) flowers in drooping racemes; most trees are either male or female (the species is essentially dioecious), but bisexual flowers occur on a few trees (technically polygamo-dioecious). Fruits are winged nutlets (samaras) in a pair, 2.5-4 cm long, clustered on long stalks. The common name refers to the resemblance of leaves to those of ash (Fraxinus). Boxelder, its other often used common name, refers to a resemblance to elder (Sambucus) and the use of the soft wood for box making.

Boxelder is unusual among American maples in having compound leaves. Apart from the opposite leaves, seedlings and young saplings of Boxelder bear a remarkable resemblance to poison ivy (Toxicodendron radicans) and are often mistaken for it by beginning naturalists.

Variation within the species:

Substantial variation occurs over the range of the species; numerous forms and varieties have been described, but only six varieties currently recognized (in some treatments, for example, see McGregor 1986). These are primarily distinguished by coloration of the branches, twig and fruit pubescence, and leaflet number.

Var. arizonicum Sarg. – Arizona and New Mexico

Var. californicum (Torr. & Gray) Sarg. – California

Var. interius (Britt.) Sarg. – midwest US into the western states

Var. negundo ­– the eastern half of the US, with naturalized western outlyers

Var. texanum Pax – south-central US

Var. violaceum (Kirchn.) Jaeger – north-central US and most of Canada less ↑

Perennial, Trees, Shrubs, Woody throughout, Nodules present, Stems or branches arching, spreading or decumbent, Stems 1-2 m tall, Stems greater than 2 m tall, Stems solid, Stems or young twigs glaucous, Stems or young twigs glabrous or sparsely glabrate, Stems or young twigs sparsely to den sely hairy, Leaves alternate, Leaves petiolate, Extrafloral nectary glands on petiole, Stipules inconspicuous, absent, or caducous, Stipules deciduous, Stipules free, Leaves compound, Leaves bipinnate, Leaf or leaflet margins entire, Leaflets opposite, Leaflets 10-many, Leaves glabrous or nearly so, Leaves coriaceous, Inflorescences racemes, Inflorescence panicles, Inflorescences globose heads, capitate or subcapitate, Inflorescence axillary, Bracts very small, absent or caducous, Flowers actinomorphic or somewhat irregular, Calyx 5-lobed, Calyx glabrous, Petals united, valvate, Petals white, Stamens numerous, more than 10, Stamens completely free, separate, Stamens long exserted, Filaments glabrous, Style terete, Fruit a legume, Fruit unilocular, Fruit tardily or weakly dehiscent, Fruit elongate, straight, Fruit oblong or ellipsoidal, Fruit coriaceous or becoming woody, Fruit exserted from calyx, Fruit glabrous or glabrate, Fruit 3-10 seeded, Seed with elliptical line or de pression, pleurogram, Seeds ovoid to rounded in outline, Seed surface smooth, Seeds olive, brown, or black, Seeds with appendage - aril, caruncle, funiculus, or strophiole. less ↑