Description

Leaves: Alternate; once pinnately compound; 8" to 14" long; deciduous; 7 to 19 elliptical, ovate-oblong or ovate leaflets, 1-1/2" to 2" long, entire margins, glabrous; dark green in summer; yellow-green fall color.

Twigs/buds: Twigs moderately stout; often zigzag; generally have short, stiff spines, 1/4" to 1/2" long, in pairs at bases of leaves.  No terminal bud; lateral buds hidden under cracks of bark near leaf scar.

Flowers/fruit: Flowers perfect, white, 1" wide, pea-like; arranged in 4" to 8" long groups; very fragrant and attractive; flowers in May to early June.  Fruit a dark brown, flat legume; 3" to 5" long; containing 4-8 flat brown seeds.

Bark: Red-brown to nearly black; deeply furrowed into cris-crossing scaly ridges; inner bark may be poisonous.

Wood: Moderately important; sapwood yellow; heartwood yellow to golden-brown and rot-resistant; growth rings distinct; ring-porous; rays generally visible to the naked eye; used for fence posts, railroad ties, etc.

General: Native to the central-eastern U.S.  Widely planted and naturalized east of the Rockies.  Fast growing and well-adapted to a wide variety of sites.  Nitrogen fixer.  Readily produces sucker sprouts.  Shade intolerant.  May be insect and/or disease prone, especially when stressed.  Thorns or spines that can be dangerous; use thornless varieties if possible.  Sucker (sprout) growth can be a problem.

Landscape Use: An old pioneer tree that is not planted much any more, but should be used, especially under tough conditions.  An attractive medium to large-sized tree with a narrow canopy and an interesting texture, especially in winter.  The attractive, fragrant flowers and the foliage are very nice and the bark is interesting.  Unfortunately, it is somewhat pest-prone, with the locust borer especially bad.  Zones 3-9. 

Cultivars: 'Aurea', 'Bessoniana', 'Dean Rossman', 'Fibermaster', 'Frisia', 'Lace Lady', 'Purple Robe', 'Pyramidalis', 'Semperflorens', 'Tortuosa', 'Umbraculifera', 'Unifoliola'.

Characteristics