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Acacia constricta

White thorn or Whitethorn acacia

In a wildlife garden, birds find shelter within the spiny branches.

Tall deciduous shrub or a small tree, with an upright, open and airy appearance. Small leaves are divided into pairs of very small leaflets, alternately arranged on the flexible stems, but look like they?re in clusters. The shrub has light gray to mahogany-colored bark and pairs of straight white spines. Small round fragrant yellow flower heads occur in clusters, releasing their aroma in early spring. Long, narrow seed pods are indented or ?constricted? between the seeds, gradually twisting before splitting and releasing the seeds.


QuickFacts Description Growth Forms: Shrub. Mature Height: 6-10 feet Mature Width: 15 feet Predominant Flower Color: Yellow Flowering Seasons: Fore-Summer (May - June), Summer Rainy Season (July - mid September) Gardening Planting Zone: Arid or natural zone Water Use: Low Exposure: Full Sun Hardy to: Below 10° F Planting Season: Spring (mid February - April), Fall (October - November) Availability: Nurseries specializing in native plants and botanical garden nurseries In the Wild Habitat: Washes, gravelly plains and rocky hillsides Elevation: 2000 to 5000 feet Native Range: Texas to Arizona and Mexico

Landscape Use: Barrier, Bird Garden, Native Plant Garden, Natural Area, Patio Area, Screen, Fragrance Garden, Wildlife Garden.

White thorn blends perfectly with naturalistic or revegetated desert landscapes, especially where wildlife is enjoyed. The flowers, which appear intermittently in the summer, have a delicious fragrance. The speckled shade of white thorn provides enough light to grow wildflowers and cactus beneath it, but avoid planting things that require a lot of water because that will cause the plant to become gangly and unnatural in shape. White thorn can be used as a hedge or barrier to deter any intruder.

Planting Tips: Plant from one- or five-gallon containers at any time of the year, in full sun. White thorn can go right into native soil, although establishment will be speeded up by digging the hole just slightly deeper than the root ball, but several times wider. Water the immediately after planting.

Gardening Tips: Water weekly the first two months after planting, then stretch out to every two weeks. Once established, white thorn can thrive with watering once a month and can be pretty much ignored during the winter. It doesn?t need much in the way of pruning, but trim branches that encroach on walkways any time. This sturdy native does not need fertilizing.

Problems: Spines are sharp. Keep plants away from walkways and where people are active. Seeds may germinate easily in irrigated areas. Plants are bare of leaves in winter.

Attracting Wildlife

Wildlife Attraction: Birds.
Wildlife Use: Verdins glean insects and nectar from the yellow flowers. Plants also provide nesting sites and hiding places.

Names

Family: Fabaceae (Legume Family)
Scientific Name (Genus species): Acacia constricta
Pronounced ah-KAY-shah. The Greek word <i>akakie</i> means ?sharp point,? a reference to the thorns of many members of the genus <i>Acacia</i>. ?Constricta? refers to the seed pod which is narrowed or constricted between each seed.
Common Names: White thorn, Whitethorn acacia

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