Many desert dwellers, including visitors to the Southwest, are struck by the beauty of Chilopsis linearis, or the desert willow. Indisputably, desert willow has outstanding practical and ornamental value as a vigorous tree that gets smothered with large, fragrant blossoms during the spring and summer. Few realize, however, desert willow's many uses, or its' significance to Native American peoples - past and present. But...before it is story-telling time, I can't resist giving a bit of background information and showering more kudos on Chilopsis linearis.

Ornamental Value
Desert willow, one of the few trees in the Sonoran Desert that is not a legume, is a member of the Bignoniaceae (Trumpet-creeper) family. It is often confused with Salix species in the Salicaceae (Willow) family, but Chilopsis linearis is not a true willow. Willows in the Sonoran Desert region have inconspicuous flowers in catkins. Check out the bodacious flowers of the desert willow and you'll never confuse the two families ever again! Desert willows produce a profusion of catalpa-like flowers in terminal racemes in late April or May. With good summer rains, flowering will extend through September. The trumpet-shaped, 1 1/2" long corollas range from almost a pure white to intense purple, and are often tinged, streaked, or spotted with pinkish-purple and yellow in the throat. These spectacular orchid-like blooms exude a heavy, musky fragrance which is reminiscent of sweet violets. What more can anyone ask for? Okay, if that isn't enough, hold your hat, because there is a lot more going for the desert willow than just beautiful flowers.

Chilopsis linearis is a super selection for a mini-oasis garden, transition zone, parking area, pathsides, school grounds, or in a natural revegetation area. This graceful, multi-stemmed large shrub or small tree reaches up to 20' and spreads to 30' and...yippee...the branches are devoid of spines and thorns! It is moderately fast growing, and its' trunk expands to 1' in diameter with the fissured, scaly gray bark turning dark brown with age. The slightly weeping habit of the crown casts a light shade in the summer. The lanceolate leaves, as wide as your baby finger, are slightly curved with smooth margins. Mature ribbon-like pods decorate the tree through the winter, and split open length-wise revealing many flat seeds that have little tufts of hairs.

The Arizona Department of Water Resources recommends desert willow as a low water use/drought-tolerant tree. Keep in mind though, that monthly irrigation during the summer months maximizes the desert willow's ornamental value. Moderate water use is beneficial, but not critical for survival of the tree. Desert willow is no wimp. It is hardy to minus 10 degrees Fahrenheit, has deep roots that extend 50'+, waxy leaves that effectively retain moisture, and is highly responsive to cold and drought. The first hard frost will disrobe the entire tree. Have no fear because fresh leaves "spring-out" during March through May.

The heat and drought in June and July will again strip the tree, but summer rains in August will clothe desert willow with a light green cloak of leaves.

In siting desert willow, keep in mind that leaf and twig litter will accumulate around the base of the tree. Also, watch for volunteer seedlings that may pop up in the vicinity. Some may find the long, slender seed pods undesirable. The textural effect of the pods is really quite interesting; but branches can easily be pruned back if you prefer the manicured look. Winter pruning will not affect future bloom, as desert willow blooms on the current year's growth. Prune it back to a single trunk if you prefer, or allow it to naturally express itself in all its' multi-trunked glory.

Habitat
The primary habitat of desert willow is in riparian areas between 1,500 and 5,500 feet, but is primarily found at lower elevations. It naturally grows along washes and other desert waterways, in grasslands and oak-juniper woodlands, foothills, and mesas. As a water indicator in the desert, desert willow is considered a phreatophyte. Wherever it is growing, you can count on water to be near the surface at least part of the year. The range extends from western Texas to southern Nevada, Arizona, southern California, and northern Mexico, and as far north as Kansas. The flowers are typically nearly white in the western end of its' range, to deep purple at the eastern end. It is a shrub in the northern areas because it will freeze down to the ground. Desert willow has soft wood, flexible trunks, sprouts readily, and is adapted to growing in alluvial soils and in dunes. It effectively controls erosion along banks of washes and provides cover for many creatures.

High-held blooms allow perfect viewing of the hummingbirds, bees, lady-beetles, small flies, and other insects that visit the nectaries on the flowers and leaves. Large black carpenter bees (Bombus sonorus) are the primary pollinators in southeastern Arizona. The platform on lower lip of the floral tube has elaborate nectar guides to invite the bees inside the corolla. The flowers will not self-pollinate, as the styles fold shut when touched. As is the case with most insect-pollinated trees, desert willow is considered non-allergenic.

Ethnobotanical significance
Native Americans, and others "in-the-know," use desert willow in a multitude of ways. Most of the literature, however, describes the primary use of Chilopsis linearis as medicinal. In northern Mexico, the dried flowers are widely used to make into a tea or a hot poultice, for suppressing coughs, for a tight dry sore throat, rapid heartbeat, and treating other chest and lung ailments. Flowers are gathered and dried carefully. They are high in nectar and spoil easily. The leaves and bark are quite sturdy and easy to dry. Flowers will last up to 6 months, and the bark and leaves will last in perpetuity. The leaves and bark are antiseptic and antifungal, and are used powdered, or as a wash, to treat skin infections, ringworm, and other tineas, or taken internally, as a douche for candidiasis. Candida albicans infections, which cause digestive distress can be inhibited with treatments prepared with desert willow. Powdered leaves and bark are also an excellent first aid for hikers, dusted liberally on scratches and scrapes. A tincture can be used, but be prepared for a bit of a sting. Chilopsis linearis has low toxicity, but as always, it is wise to consult a physician for advice on the use of any medicine.

The primary constituents are anthocyanins in the flowers, tienoic fatty acids in the seeds, and alkanes, piperdine alkaloid, and squalene in the leaves and branches. The bark and wood also have tecomin. Desert willow is a source of polyphenols (collectively tannins and phenolic compounds) which hold promise as a source of adhesives, and in textile, and leather industries. The wood has been used to make bows and fence posts. The slender branches can be woven into baskets.

Amadeo Rea recounts in the creation story of the Gila River Pima in At the Desert's Green Edge- "...early in mythic time, after Toobi ‘Cottontail,' the first victim of Rattlesnake, died, the council decided to cremate his body. Coyote stole Cottontail's heart from the pyre and fled south to Sierra Estrella. He paused, and placed the heart on an aan bush..." Rea also describes how the Gila River Pima used desert willow for thatching to cover the vatto (ramada) Rain on the vatto drips from the roof into the water ollas, and gives the water a distinctive taste. Rea interviewed a man named Sylvester who said, "We used to live in Queen Creek and we go chop those aan, Desert-willow, to make our vatto in camp. It grows there in Queen Creek."

It just so happens that Queen Creek is the place to go check out desert willows, and the home of Arid Zone Trees. Coincidence? I think not. I highly recommend a visit to the nursery to fully appreciate desert willow and the multitude of other beautiful tree species at AZT.