Pithecellobium mexicanum (Havardia mexicanum) Mexican Ebony
Foliage: Deciduous
Mature Height: 15’ - 20’
Mature Width: 10’ - 15’
Growth Rate: Fast
Hardiness: 15 degrees F
Exposure: Full Sun
Leaf Color: Green
Shade: Filtered
Flower Color: Cream
Flower Shape: Ball
Flower Season: Spring
Thorns: Yes
Propagation Method: Seed
Sizes Available: Not in Production at AZT
Combining the growth rate and adaptability of Thornless Mesquites and the structure and appearance of the Desert Ironwood, Mexican Ebony (Pithecellobium mexicanum) is a versatile and underutilized desert landscape tree. With small gray-green leaflets, an open canopy and smooth, chalky gray trunks, its appearance mimics Desert Ironwood. The growth rate approaches that of Thornless Mesquite. In warm micro-climates, it retains most of its foliage, through the desert winter months. The lacy leaf canopy, smooth, curving, chalky gray trunks make Mexican Ebony, also called Palo Chino, a tree that can substitute for or be inter-planted with Ironwoods. Unlike Ironwoods, it can be planted in a wide variety of landscape settings including turf areas or mixed with under-story plantings that require regular, year round irrigation.
The tree is native to the Mexican states of Sonora, Sinaloa and southern Baja. In natural settings trees are found growing in arroyos, desert slopes and valley floors. They cannot be naturalized in desert landscape settings and will require some summer irrigation. Both the small leaflets and immature bark are a pale gray-green. The bark fissures and darkens slightly as trunks and branches mature. It is hardy to 15 F and armed with small cat-claw like thorns. Cream colored blooms appear in March and April with 1 to 3 inches long, thick brown pods maturing by mid-summer. In the desert, trees mature to about 20' tall and 15' wide. In landscape settings, with the benefit of regular irrigation, fertilization and well-drained soils, they may grow larger.
Mexican Ebony provides filtered shade that is ideal for promoting the growth and flowering of under-story plantings. With its striking color and form it can be used as an accent tree, at entry monuments or any application where Ironwoods would be attractive. They work well as a perimeter planting or as a transition tree from landscaped areas to undisturbed desert.
The information provided here was gathered from research literature published by the University of Arizona, other professional landscape and horticulture organizations and our experience at Arid Zone Trees. Always consult local landscape experts for recommendations for your specific area.