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Amorpha fruticosa - false indigo bush

Scientific Family
Fabaceae
Synonyms
Amorpha bushii, Amorpha croceolanata, A. curtissii, A. dewinkeleri, for more synonyms see USDA Plants database.
Other common names
bastard indigo
indigo bush
spice-bush
Plant type
Shrubs
Riparian
Yes

Plant Description

Origin
Native
Similar species
Amorpha californica

A tall, leggy, loose, airy, minutely hairy shrub with compound leaves that grows in dense stands along stream banks and wherever there is moisture. The majority of foliage is on the upper third of the plant.

Shrub without prickly glands; leaves compound with minutely hairy, oval-shaped, spine-tipped leaflets; flower cluster is spike-shaped with flowers on short stems; single purple petal and 10 protruding stamens with yellow anthers; fruit is a smooth pod.

Height
Up to 10 feet
Width
5 feet

Habitat

Habitat description

In canyons and along stream banks.

Plant Community
Riparian
Low elevation
2500
High elevation
6500

Leaves

Leaf color
Grayish-green
Leaf type
Compound
Leaf shape
Round or oval
Leaf margin
Smooth
Leaf attachment
Alternate
Leaf hairs
Bottom of leaves
Spines
No
Leaf Drop
Deciduous

Darker above, lighter below, about 10 inches long, with 11 to 21 oblong leaflets. Leaflets are velvety on the lower surface, often abruptly rounded at both ends with a small point at their apex; leaflet margins are sometimes almost parallel.

Flowers

Flower color
Deep bluish-purple
Flower shape
Irregular
Tubular
Yes
First bloom month
May
Last bloom month
July

Deep bluish-purple flowers have 1 petal; anthers long bright orange or yellow, 3/8 inch long by 1/8 inch wide. Dense showy flower spikes to 7 inches long are on slender stems at the ends of branches. Sepals less than 1/2 the length of the floral tube.

Flower clusters
Elongated

Fruit

Fruit color
Green
Fruit type
Pod

Pods are glandular dotted and usually contain only 1 seed. Similar to tiny cucumbers, bright green and drying to brown. Pods are from 1/4 to 1/2 inch long and smooth.

Bark/Branches

Bark color
Brownish
Bark texture
Smooth

Twigs are grayish-brown and somewhat grooved below the nodes.