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Mojave Desert Plants >
Desert WillowChilopsis linearis
SCS PLANT CODE : CHLI2
ABBREVIATION : CHILIN
COMMON NAMES : desert willow, desertwillow, flowering willow, flowering-willow, willowleaf catalpa, desert catalpa, catalpa willow, false-willow, bow willow, mimbre, Flor de Mimbre, jano
TAXONOMY : The currently accepted scientific name of desert willow is Chilopsis linearis (Cav.) Sweet [17,27,49].
Chilopsis is a monotypic genus native to the southwestern United States and northern Mexico. It is a member of the Bignoniaceae family, and is most closely related to the genus Catalpha Scop. Presented below is a recent taxonomic revision of Chilopsis, which divides the species into 3 subordinate taxa based primarily on leaf morphology and growth form : Chilopsis linearis (Cav.) Sweet
var. linearis - Chihuahuan Desert
var. tomenticaulis Henrickson - eastern Mexico
ssp. arcuata (Fosberg) Henrickson - Sonoran and Mojave Deserts
GENERAL DISTRIBUTION :
Desert willow is distributed from southwestern and Trans-Pecos Texas west to extreme southwestern Utah, southern Nevada, and southern California . It is also found in northern Mexico.
Subspecies linearis var. linearis occurs primarily east of the Rio Grande River in eastern New Mexico and western Texas, while subspecies arcuata occurs primarily west of the Rio Grande River .
FRES30 Desert shrub
FRES32 Texas savanna
FRES33 Southwestern shrubsteppe
FRES40 Desert grasslands
STATES : AZ CA NV NM TX UT MEXICO
BLM PHYSIOGRAPHIC REGIONS :
7 Lower Basin and Range
12 Colorado Plateau
13 Rocky Mountain Piedmont
KUCHLER PLANT ASSOCIATIONS :
K027 Mesquite bosque
K042 Creosotebush - bursage
K043 Paloverde - cactus shrub
K044 Creosotebush - tarbush
K054 Grama - tobosa prairie
K058 Grama - tobosa shrubsteppe
K059 Trans-Pecos shrub savanna
K061 Mesquite - acacia savanna
SAF COVER TYPES :
HABITAT TYPES AND PLANT COMMUNITIES :
Desert willow sometimes codominates desert washes and water courses with other phreatophytes [see SITE CHARACTERISTICS for a list of codominant plants].
SPECIES: Chilopsis linearis
WOOD PRODUCTS VALUE : Desert willow is occasionally used for fence posts and fuel [14,46].
IMPORTANCE TO LIVESTOCK AND WILDLIFE : Livestock: Livestock generally do not browse desert willow. It is consumed only when other forage is scarce [18,46].
Wildlife: Various species of birds eat desert willow seeds [12,46]. Hummingbirds are attracted to the showy flowers and feed on the nectar [3,12]. Mule deer eat small quantities of the leaves and fruit .
PALATABILITY : Desert willow is considered to be unpalatable to livestock and low in palatability to wildlife . The presence of cyanogenic glycosides may account for its low palatability . Following fire, however, tender sprouts may be highly palatable. Two months after a July wildfire in southern California, 55 percent of available desert willow sprouts were browsed by mule deer, bighorn sheep, and cottontail rabbits, but this use declined to about 1 percent within 1 year .
NUTRITIONAL VALUE : The sucrose in desert willow nectar is a good energy source for bees and hummingbirds .
COVER VALUE : Desert willow provides nesting sites for desert songbirds and cover for other wildlife species .
VALUE FOR REHABILITATION OF DISTURBED SITES : Desert willow is used in soil stabilization plantings. It is often used along highways and in well-drained barrow ditches . Numerous cultivars are available, including 'Barranco', released by the Soil Conservation Service , and 'White Storm', 'Dark Storm', 'Marfa Lace', 'Alpine', and 'Tejas', released in 1988 from the Texas A&M Research and Extension Center [36,39]. It is usually transplanted from nursery stock. Removing competing vegetion around transplants and irrigating during the first season after transplanting is recommended . Methods for growing seedlings in a nursery have been discussed [15,48]. Plants may be successfully propogated by both softwood and hardwood cuttings [7,48].
OTHER USES AND VALUES : Desert willow is cultivated as an ornamental because of its attractive flowers . It has been used for roadside beautification, border rows, screenings, and mass plantings . In the 1930's the Civilian Conservation Corps planted desert willow in shelterbelts . Indians used the wood to make bows and baskets [35,46].
OTHER MANAGEMENT CONSIDERATIONS : Use of desert willow by livestock generally indicates overbrowsing or overstocking of the range [45,48].
BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Chilopsis linearis
GENERAL BOTANICAL CHARACTERISTICS : Desert willow is a large deciduous shrub or small tree that may grow 10 to 30 feet (3-9 m) tall, and often has a leaning trunk and an open, spreading crown [18,25,46]. Basal diameter of the trunk rarely exceeds 5 inches (12.5 cm) . The dark brown bark is very thin, up to about 0.25 inch (6.3 mm) thick . Pale green willowlike leaves are about 5 inches (12.5 cm) long and less than 0.5 inch (1.25 cm) wide with smooth margins [27,46]. The pink to light violet flowers are 1.25 inches (3.2 cm) long and wide, and occur in clusters up to 4 inches (10 cm) long at the end of the twigs . The fruit is a narrow, elongated two-celled podlike capsule 4 to 10 inches (10-30 cm) long . First year twigs are green but later turn gray to reddish-brown .
Henrickson  provides a key for separating subspecies and varieties.
RAUNKIAER LIFE FORM :
Undisturbed State: Phanerophyte (microphanerophyte)
Burned or Clipped State: Hemicryptophyte REGENERATION PROCESSES : Desert willow reproduces sexually by producing abundant seed. Flowers are primarily pollinated by numerous species of bees and hummingbirds . Large numbers of flowers are produced continuously over several weeks . Desert willow flowers are self incompatible. Fruit set may be limited by insufficient amounts of outcrossed pollen and by inadequate movement of pollinators between trees . Fruit production does not appear to be limited by inadequate moisture, probably because plants are primarily found along washes.
Several 0.33 inch (8 mm) long, light brown, oval seeds are encased within a two-celled capsule . Seeds have a fringe of soft white hairs at each end which aid in wind dispersal [26,30]. Seeds do not display dormancy, and probably only remain viable until the spring following dispersal . There are between 50,000 and 100,000 seeds per pound (110,200-220,400/kg) [26,45]. Germination has been reported between 40 and 60 percent . Commercial seed has shown 92 percent purity and 87 percent soundness .
Sprouting: Following damage to the aboveground portion of the plant, such as by fire, most plants regenerate by sprouting from the root crown .
SITE CHARACTERISTICS : Desert willow primarily occupies dry washes, intermittent streams and other water courses, and moist canyons in deserts and mountain foothills [4,16,18,27,35,49]. These sites generally have underground water available year-round. Plants can withstand seasonal flooding quite well, and often occupy the middle of drainage channels, sometimes covering broad expanses in wash areas [10,16].
Soils: Sites are mostly well drained, neutral to basic and mildly saline . Soils are mostly sandy to gravelly alluvium [29,35,48].
Associated species: Common associates of desert washes include blue paloverde (Cerdidium floridum), desert ironwood (Olneya tesota), catclaw acacia (Acacia greggii), smoketree (Dalea spinosa), mesquites (Prosopis spp.), desertbroom (Baccharis sarothroides), netleaf hackberry (Celtis reticulata), littleleaf sumac (Rhus microphylla), Arizona walnut (Juglans major), velvet ash (Fraxinus velutina), spitleaf brickellia (Brickellia laciniata), cottontop (Digitaria californica) and southwestern condalia (Condalia lycoides) [4,10,16,29,31,48].
Elevational range by location:
below 4,000 feet (1,219 m) AZ 
below 5,000 feet (1,524 m) CA 
below 4,920 feet (1,500 m) UT 
SUCCESSIONAL STATUS : Desert willow sometimes invades freshly deposited channel sediments following seasonal water runoff. As plants develop they may trap sediments, leading to the formation of islands within the channel .
Desert willow plants are long-lived and help stabilize the banks of water courses. Desert willow is a component of desert wash communities that are somewhat stable.
SEASONAL DEVELOPMENT : Since desert willow is primarily restricted to washes or water courses with available underground water, it is able to maintain a full compliment of leaves during the summer months even though it is not well adapted to high temperatures . Plants are winter deciduous and drop leaves in late fall following the first hard frost . Leaf drop may be photoperiodically controlled, as plants in temperature controlled greenhouses lose their leaves during the winter .
Flowering occurs mostly in May and June but may occur later in the summer after rain . Most fruits ripen from late summer to fall, and the capsules persist overwinter [46,48]. Under extremely dry conditions, plants may fail to form fruits . In a wash near Tucson, Arizona, flowering occurred mostly in May and June, and most fruits were mature by September 2 .
Flowering time by location is as follows:
May - September s CA 
April - August AZ 
April - September w TX 
SPECIES: Chilopsis linearis
FIRE ECOLOGY OR ADAPTATIONS : Desert willow primarily occurs in washes wich rarely burn . It is able to sprout from the root crown following top-kill by fire [41,42].
POSTFIRE REGENERATION STRATEGY : survivor species; on-site surviving root crown or caudex
SPECIES: Chilopsis linearis
IMMEDIATE FIRE EFFECT ON PLANT : Most fires probably top-kill desert willow. In southern California, a July wildfire in a chaparral-desert ecotone resulted in nearly all desert willow plants being charred and defoliated, but less than 10 percent of the plants were killed .
DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY
PLANT RESPONSE TO FIRE : Following top-kill by fire, desert willow survives by producing numerous root crown sprouts. Following a July wildfire in southern California, more than 90 percent of desert willow plants survived . These residual plants started sprouting within 2 months after the fire. Plants developed a multistemmed growth form and averaged 171 sprouts per plant 10 months after this fire.
References for species: Chilopsis linearis
1. Bernard, Stephen R.; Brown, Kenneth F. 1977. Distribution of mammals, reptiles, and amphibians by BLM physiographic regions and A.W. Kuchler's associations for the eleven western states. Tech. Note 301. Denver, CO: U.S. Department of the Interior, Bureau of Land Management. 169 p. 
2. Brown, David E. 1982. Semidesert grassland. In: Brown, David E., ed. Biotic communities of the American Southwest--United States and Mexico. Desert Plants. 4(1-4): 123-131. 
3. Brown, James H.; Kodric-Brown, Astrid; Whitham, Thomas G.; Bond, Hedley W. 1981. Competition between hummingbirds and insects for the nectar of two species of shrubs. The Southwestern Naturalist. 26(2): 133-145. 
4. Burk, Jack H. 1977. Sonoran Desert. In: Barbour, M. G.; Major, J., eds. Terrestrial vegetation of California. New York: John Wiley and Sons: 869-899. 
5. Dayton, William A. 1931. Important western browse plants. Misc. Publ. 101. Washington, DC: U.S. Department of Agriculture. 214 p. 
6. DePree, Elaine; Ludwig, John A. 1978. Vegetative and reproductive growth patterns in desert willow (Chilopsis linearis (Cav.) Sweet). The Southwestern Naturalist. 23(2): 239-246. 
7. Everett, Percy C. 1957. A summary of the culture of California plants at the Rancho Santa Ana Botanic Garden 1927-1950. Claremont, CA: The Rancho Santa Ana Botanic Garden. 223 p. 
8. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. 
9. Freeman, C. E.; Dick-Peddie, W. A. 1970. Woody riparian vegetation in the Black and Sacramento Mountain ranges, southern New Mexico. The Southwestern Naturalist. 15(2): 145-164. 
10. Gardner, J. L. 1951. Vegetation of the creosotebush area of the Rio Grande Valley in New Mexico. Ecological Monographs. 21: 379-403. 
11. Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others]. 1977. Vegetation and environmental features of forest and range ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of Agriculture, Forest Service. 68 p. 
12. Gullion, Gordon W. 1964. Contributions toward a flora of Nevada. No. 49: Wildlife uses of Nevada plants. CR-24-64. Beltsville, MD: U.S. Department of Agriculture, Agricultural Research Service, National Arboretum Crops Research Division. 170 p. 
13. Henrickson, James. 1985. A taxonomic revision of Chilopsis (Bignoniaceae). Aliso. 11(2): 179-197. 
14. Johnson, Carl M. 1970. Common native trees of Utah. Special Report 22. Logan, UT: Utah State University, College of Natural Resources, Agricultural Experiment Station. 109 p. 
15. Johnson, E. W. 1963. Ornamental shrubs for the Southern Great Plains. Farmer's Bull. 2025. Washington, DC: U.S. Department of Agriculture. 62 p. 
16. Johnson, Hyrum B. 1976. Vegetation and plant communities of southern California deserts--a functional view. In: Latting, June, ed. Symposium proceedings: plant communities of southern California; 1974 May 4; Fullerton, CA. Special Publication No. 2. Berkeley, CA: California Native Plant Society: 125-164. 
17. Kartesz, John T.; Kartesz, Rosemarie. 1980. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. Volume II: The biota of North America. Chapel Hill, NC: The University of North Carolina Press; in confederation with Anne H. Lindsey and C. Richie Bell, North Carolina Botanical Garden. 500 p. 
18. Kearney, Thomas H.; Peebles, Robert H.; Howell, John Thomas; McClintock, Elizabeth. 1960. Arizona flora. 2d ed. Berkeley, CA: University of California Press. 1085 p. 
19. Kuchler, A. W. 1964. Manual to accompany the map of potential vegetation of the conterminous United States. Special Publication No. 36. New York: American Geographical Society. 77 p. 
20. Lamb, S. H. 1971. Woody plants of New Mexico and their value to wildlife. Bull. 14. Albuquerque, NM: New Mexico Department of Game and Fish. 80 p. 
21. Little, Elbert L., Jr. 1976. Atlas of United States trees. Volume 3. Minor western hardwoods. Misc. Publ. 1314. Washington, DC: U.S. Department of Agriculture, Forest Service. 13 p. 290 maps. 
22. Little, Elbert L., Jr. 1979. Checklist of United States trees (native and naturalized). Agric. Handb. 541. Washington, DC: U.S. Department of Agriculture, Forest Service. 375 p. 
23. Ludwig, John A.; Reyolds, James F.; Whitson, Paul D. 1975. Size-biomass relationships of several Chihuahuan Desert shrubs. The American Midland Naturalist. 94(2): 451-461. 
24. Stickney, Peter F. 1989. Seral origin of species originating in northern Rocky Mountain forests. Unpublished draft on file at: U.S. Department of Agriculture, Forest Service, Intermountain Research Station, Fire Sciences Laboratory, Missoula, MT; RWU 4403 files. 10 p. 
25. MacMahon, James A. 1985. The Audubon Society nature guides: Deserts. New York: Alfred A. Knopf, Inc. 638 p. 
26. Magill, Arthur W. 1974. Chilopsis linearis (Cav.) Sweet desertwillow. In: Schopmeyer, C. S., technical coordinator. Seeds of woody plants in the United States. Agric. Handb. 450. Washington, DC: U.S. Department of Agriculture, Forest Service: 321-322. 
27. Munz, Philip A. 1974. A flora of southern California. Berkeley, CA: University of California Press. 1086 p. 
28. Paysen, Timothy E.; Derby, Jeanine A.; Black, Hugh, Jr.; [and others]. 1980. A vegetation classification system applied to southern California. Gen. Tech. Rep. PSW-45. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Forest and Range Experiment Station. 33 p. 
29. Pemberton, Robert W. 1988. The abundance of plants bearing extrafloral nectaries in Colorado and Mojave Desert communities of southern California. Madrono. 35(3): 238-246. 
30. Pendleton, Rosemary L.; Pendleton, Burton K.; Harper, Kimball T. 1989. Breeding systems of woody plant species in Utah. In: Wallace, Arthur; McArthur, E. Durant; Haferkamp, Marshall R., compilers. Proceedings--symposium on shrub ecophysiology and biotechnology; 1987 June 30 - July 2; Logan, UT. Gen. Tech. Rep. INT-256. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station: 5-22. 
31. Petersen, C.; Brown, J. H.; Kodric-Brown, A. 1982. An experimental study of floral display and fruit set in Chilopsis linearis (Bignoniaceae). Oecologia. 55(1): 7-11. 
32. Powell, A. Michael. 1988. Trees & shrubs of Trans-Pecos Texas including Big Bend and Guadalupe Mountains National Parks. Big Bend National Park, TX: Big Bend Natural History Association. 536 p. 
33. Raunkiaer, C. 1934. The life forms of plants and statistical plant geography. Oxford: Clarendon Press. 632 p. 
34. Short, Henry L. 1977. Food habits of mule deer in a semi-desert grass-shrub habitat. Journal of Range Management. 30: 206-209. 
35. Simpson, Benny J. 1988. A field guide to Texas trees. Austin, TX: Texas Monthly Press. 372 p. 
36. Simpson, Benny J.; Hipp, Billy W.; McWilliams, Edward L. 1989. 'White Storm' and 'Dark Storm' desert willow. HortScience. 24(1): 178-179. 
37. Smith, G. Shannon; Pittcock, Kim. 1989. The collector's quest. American Nurseryman. 169(1): 56-65. 
38. Steger, Robert E.; Beck, Reldon F. 1973. Range plants as ornamentals. Journal of Range Management. 26: 72-74. 
39. Tipton, Jimmy L. 1988. 'Marfa Lace', 'Alpine', and 'Tejas' desert willows. HortScience. 23(4): 782. 
40. Thornburg, Ashley A. 1982. Plant materials for use on surface-mined lands. SCS-TP-157. Washington, DC: U.S. Department of Agriculture, Soil Conservation Service. 88 p. 
41. Tratz, Wallace Michael. 1978. Postfire vegetational recovery, productivity, and herbivore utilization of a chaparral-desert ecotone. Los Angeles, CA: California State University. 133 p. Thesis. 
42. Tratz, Wallace M.; Vogl, Richard J. 1977. Postfire vegetational recovery, productivity, and herbivore utilization of a chaparral-desert ecotone. In: Mooney, Harold A.; Conrad, C. Eugene, technical coordinators. Proceeedings of the symp. on the environmental consequences of fire & fuel management in Mediterranean ecosystems; 1977 August 1-5; Palo Alto, CA. Gen. Tech. Rep. WO-3. Washington, DC: U.S. Department of Agriculture, Forest Service: 426-430. 
43. Turner, Raymond M.; Brown, David E. 1982. Sonoran desertscrub. In: Brown, David E., ed. Biotic communities of the American Southwest--United States and Mexico. Desert Plants. 4(1-4): 181-221. 
44. U.S. Department of Agriculture, Soil Conservation Service. 1982. National list of scientific plant names. Vol. 1. List of plant names. SCS-TP-159. Washington, DC. 416 p. 
45. Van Dersal, William R. 1938. Native woody plants of the United States, their erosion-control and wildlife values. Washington, DC: U.S. Department of Agriculture. 362 p. 
46. Vines, Robert A. 1960. Trees, shrubs, and woody vines of the Southwest. Austin, TX: University of Texas Press. 1104 p. 
47. Virginia, Ross A.; Bainbridge, David A. 1988. Revegetation in the Colorado Desert: lessons from the study of natural systems. In: Rieger, John P.; Williams, Bradford K., eds. Proceedings, 2nd native plant revegetation symposium; 1987 April 15-18; San Diego, CA. Madison, WI: University of Wisconsin - Arboretum, Society of Ecological Restoration and Management: 52-63. 
48. Wasser, Clinton H. 1982. Ecology and culture of selected species useful in revegetating disturbed lands in the West. FWS/OBS-82/56. Washington, DC: U.S. Department of the Interior, Fish and Wildlife Service. 347 p. 
49. Welsh, Stanley L.; Atwood, N. Duane; Goodrich, Sherel; Higgins, Larry C., eds. 1987. A Utah flora. The Great Basin Naturalist Memoir No. 9. Provo, UT: Brigham Young University. 894 p. 
50. Wisdom, Charles S.; Gonzalez-Coloma, Azucena; Rundel, Philip W. 1987. Phytochemical constituents in a Sonoran Desert plant community. In: Provenza, Frederick D.; Flinders, Jerran T.; McArthur, E. Durant, compilers. Proceedings--symposium on plant-herbivore interactions; 1985 August 7-9; Snowbird, UT. Gen. Tech. Rep. INT-222. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station: 84-87. 
AUTHORSHIP AND CITATION :
Uchytil, Ronald J. 1990. Chilopsis linearis. In: Fire Effects Information System, [Online].
U.S. Department of Agriculture, Forest Service,
Rocky Mountain Research Station, Fire Sciences Laboratory (Producer).
Available: http://www.fs.fed.us/database/feis/ [2012, October 2].