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Scientific: Olneya tesota
Common: desert ironwood
Family: Fabaceae (Leguminosae)
Origin: Lower Sonoran Desert, highest frequency of occurrence in southeastern California and southwestern Arizona.

Pronounciation: Ol-NEY-ya te-SO-ta

Hardiness zones:
Sunset 12-13
USDA 9-11 (arid zones only)

Landscape Use: Native desert tree for light shade and accent in most any desert landscape design type, even wayside, roadside or desert picnic desert landscape settings, or front yard decorations.

Form & Character: Upright and irregular, rugged and twisting, dry looking with a picturesque trunk character, gray, recessive.

Growth Habit: Semi-evergreen, woody, perennial tree, medium growth rate to 30 feet with equal spread, final height depends largely on whether the trees are irrigated or not. Irrigated trees wikll produce copious numbers of trunk suckers (epicormic shoots or water sprouts) under landscape conditions.

Foliage/Texture: Small, gray-green pinnately-compound, small leaves, 4 to 12 pairs of leaflets, paired recurvate stipular spines below leaves at nodes are quite nasty....and very persistent remaining on the stems and branches long after the leaves have abscissed; medium fine texture.

Flowers & Fruits: Flowers produced in 2-inches long raceme, pale purple rose to lavender; fruits are pods to 2- to 3-inches long with black seeds that are shed in August.

Seasonal color: Flowers appear late April through May.

Temperature: Tolerant

Light: Full sun

Soil: Tolerant

Watering: None to only occasional summer irrigations to encourage vigor. No supplemetal water nedded during cooler times of year.

Pruning: Prune conservatively to shape, elevate canopy base (crown raise) and remove occasional epicormic shoots (water sprouts and suckers).

Propagation: Seed

Disease and Pests: None

Additional comments: Desert ironwood trees look much better when occasionally (not regularly) deeply watered in summer, although additional water will encourage growth of well-armed epicormic shoots (water sprouts and suckers). Large specimens are often salvaged from the desert, relocated, and easily transplanted. This is best done during the summer. Desert ironwood is an excellent Arizona native desert landscape tree that produces exceptionally dense heartwood.