by Cathy Rymer, Certified Arborist, Master Gardener, Water Conservation Coordinator, City of Chandler
Desert Willow, Desert Catalpa, Flowering Willow, False Willow, Jano
The long, narrow leaves of this plant are reminiscent of willows, but this imposter isn’t a willow at all. Rather, it’s a close relative of the catalpa tree and a member of the trumpet vine family (Bignoniaceae). Desert willow is drought-tolerant and can be found naturally growing along our ephemeral streambeds or washes where it is a natural protector against flood and erosion damage. From May through October colorful, large, slightly scented tubular flowers bloom making this attractive tree popular in our urban landscapes.
Spectacular silhouettes of Desert Willow are created when the winter sun sets low on the horizon. While some plants become obscure and hard to identify without their familiar green foliage, the form of Chilopsis linearis is unmistakable even without its leaves. Its branches seem to zigzag their way to the edge of the canopy. Long, narrow, papery pods hang as decorations and release their treasured seeds to hungry birds throughout the winter season.
Classification and Range
Desert willow is a deciduous large shrub or small tree that can grow to 25 feet tall and 20 feet wide. It primarily occupies dry washes, intermittent streams and other watercourses, and moist canyons in deserts and mountain foothills between 1,500 and 5,000 feet in elevation throughout much of the southwestern United States and into Mexico. Desert willow plants are long-lived and help stabilize the banks of watercourses.
A component of desert wash communities that are somewhat stable, desert willow sometimes establishes itself in freshly deposited channel sediments following seasonal water runoff. As plants develop they may trap sediments, leading to the formation of islands within the channel.
Common associates of desert washes include blue palo verde (Cercidium floridum), desert ironwood (Olneya tesota), catclaw acacia (Acacia greggii), smoketree (Dalea spinosa), mesquites (Prosopis spp.), desert broom (Baccharis sarothroides), netleaf hackberry (Celtis reticulata), and littleleaf sumac (Rhus microphylla).
The form of this tree is multi-trunked with a graceful appearance. The long, narrow, curving leaves are simple, solitary, linear, and range between 5 and 12 inches long and 1/4 to 1 inch wide with a surprisingly tough, leathery texture. Attractive white, burgundy or pink colored trumpet-shaped, orchid-like flowers with distinctive yellow throats appear in terminal clusters from May-October. The resulting seedpods are dehiscent, 4-9in long, and cling persistently on branches throughout winter. The bark of Chilopsis linearis is smooth when young but develops rough fissures with age. Prominent lenticels are noticeable on new growth. Plants are winter deciduous and drop leaves in late fall following the first hard frost but are cold hardy to 0°.
Propagation and Care
Tolerant of most soils as long as drainage is good, this tree prefers location in full sun, although it will tolerate partial shade. Established plants are considered drought-tolerant and require the deep, infrequent irrigations recommended for most desert-adapted trees. Little maintenance is required for this tree with the exception of minor selective pruning if a more tree-like form is desired. Fallen leaves and seedpods blend into a coarse groundcover. Easily propagated from seed, Desert willow can also be grown vegetatively from cuttings and is a fast grower in urban landscapes. Individuals have been selected from the wild, cross pollinated with other specimens, cloned, and marketed with characteristics such as specific flower color or growth habit. Some of the newer varieties are “Rio Salado”, "Lucretia Hamilton", "Warren Jones", and "Lois Adams".
Russian hybridizers from Tashkent, Uzbekistan, crossed the catalpa (Catalpa bignonoides) with the desert willow, which resulted in the Chitalpa (Chitalpa tashkentensis): This tree produces no seeds.
In hot, dry areas the attractive form, willow-like leaves and beautiful blooms of Chilopsis linearis are a welcome relief. It is a must-have for luring hummingbirds into a landscape. Even small native birds like verdins will be search out the nectar-producing flowers (although they tend to pierce the flower at the base as a short cut). If placed on the south, east or west side of homes it will provide shade in the summer while allowing ambient heating in the winter. Using nearby evergreen shrubs and groundcovers will lent contrast to this tree’s deciduous appearance in winter. Planted in groups, it can be used as a screen or windbreak and provides shelter for nesting birds.
<[>History & Folklore
The strong yet flexible wood of Desert-Willow was used by Indians to craft their hunting bows. The wood has also been used by the Pima to thatch roofs, in house construction and in making of baskets to store mesquite beans, acorns and other foods. The fibrous bark was used to make nets and fabrics. Important to wildlife because it provides nesting sites and cover, animals such as deer and birds also consume the leaves, fruit and the flower’s nectar. Birds eat the white-fringed seeds and bees for honey use the pollen.
The desert willow’s flowers, leaves, or bark can be used as a hot poultice or a soothing tea for coughing. Other treatments guard against yeast infections, athlete’s foot and a first-aid technique for scrapes and scratches. The plant carries an additional use as an anti-fungal and anti-candida product (yeast). The tea (from the flowers) produces a natural anti-oxidant, which promotes cardiovascular health and regulates glucose metabolism. (This section from http://medplant.nmsu.edu/chilopsis.htm).
By including one of these trees in your landscape you can have color and fragrance; attract native birds and other wildlife; and have shade and/or sun in places where it’s needed. If you’re looking for a specific flower color, shop at local nurseries when the trees are in bloom. Desert willow trees propagated from seed can vary in their flower production and color intensity. Named cultivars that are propagated vegetatively will be consistent in these characteristics. Look for a tree with good vigor and a profusion of blooms in the color you like.