Flower Color: Screw Bean Mesquite has yellow flowers in tubular spikes about 3 inches (7.6 cm) long, the fruit is a dramatic tightly coiled legumepod; the seeds are transported by water and foraging animals.
Flowering Season: May to June in Arizona; April to September in California and May to July in Texas.
Elevation: Below 4,000 feet (1,219 m).
Habitat Preferences: Desert riparian areas, wet or damp areas, desert flood plains, gravelly washes and sandy, damp or saline soils, playas and alluvial soils. In riparian areas, Screw Bean (as well as Velvet Mesquite, Prosopis velutina) form important dense wildlife supported bosques. Other, co-dominant plants found in bosques include Salt Cedar, Tamarix spp. and Arrowweed, Pluchea sericea.
Recorded Range: In the United States, Screw Bean Mesquite is found in the southwest in the states of; AZ, CA, NM, NV, TX and UT. It is also native to northern Mexico and possibly northern Baja California.
North America species range map for Screw Bean Mesquite, Prosopis pubescens:
Click image for full size map.
U.S. Weed Information: Not considered a weed in North America.
Invasive/Noxious Weed Information: All members of the genus Prosopis are listed as a Noxious Weed by the state of Florida, however Screw Bean Mesquite does is not recorded as occurring in Florida. Although several international websites list all species of the genus Prosopis as weedy.
Wetland Indicator: In North America Prosopis pubescens has the following wetland designations;
Arid West, FAC
Great Plains FAC
Western Mountains, Valleys, and Coast, FAC
FAC, Facultative, occur in wetlands and non-wetlands.
Threatened/Endangered Information: In Arizona, pursuent to Title 3, Chapter 3, A.R.S. § 3903(B)(3), Screw Bean Mesquite Prosopis pubescens is both "Salvage Assessed" and "Harvest Restricted". Permits are needed from the Department of Agriculture to transport this species off of private land and also to cut or remove the plants for their by-products, fibers, or wood.
Genus Information: In North America, USDA Plants Database lists 40native and introduced species for Prosopis. Worldwide, World Flora Online includes 64 accepted species names for the genus.
In the Southwestern United States: Arizona, California and Texas each have 4 species of Prosopis, Nevada and Utah each have 2 species, New Mexico has 3 species. Data approximate, subject to revision.
Comments: Screw Bean Mesquite may be a dominant species in lower elevation riparian areas or mesquite bosque habitats. They are often 1 of 2 or 3 other co-dominant species in the bosque habitat.
The flowers provide an important source of nectar that attract insects particularly large numbers of bee species which also serve to pollinate the plants. Wildlife and livestock eagerly eat the leaves and sweet pods of Screw Bean Mesquite.
All species of Mesquite make excellent firewood and their wood has been used for tool handles and fence-posts. Pollen from all species are reported to be responsible for hay-fever.
Screw Bean Mesquite, Prosopis pubescens their seeds are eaten by wildlife including deer and small mammals and livestock and the densely growing plants provide cover for many species of wildlife particularly birds.
Beneficial Value to Butterflies and Insects
Screw Bean Mesquite, Prosopis pubescens has attractive flowers, the flowers and their plants are visited and may be used by butterflies, moths, flies and other insects in search of nectar, food or shelter and protection.
****Special Value to Honeybees****
According to The Xerces Society for Invertebrate Conservation or other source, Screw Bean Mesquite, Prosopis pubescens, is recognized by pollination ecologists as attracting large numbers of honeybees. Click here for more information on their Pollinator Conservation Program.
****Special Value to Native Bees****
According to The Xerces Society for Invertebrate Conservation or other source, Screw Bean Mesquite, Prosopis pubescens, is recognized by pollination ecologists as attracting large numbers of Native bees. Click here for more information on their Pollinator Conservation Program.
****Provides Nesting Materials/Structure for Native Bees****
According to The Xerces Society for Invertebrate Conservation or other source, Screw Bean Mesquite, Prosopis pubescens, is recognized by pollination ecologists as providing nesting materials/structure for native bees; A plant that native bees nest beneath, within, or harvest parts from to construct their nests. Click here for more information on 5 Ways to Increase Nesting Habitat for Native Bees.
U.S. Forest Service; Fire Effects Information System (FEIS)
See the U.S. Forest Service online collection of reviews of the scientific literature for management considerations of Screw Bean Mesquite, Prosopis pubescens, are found here.
The genus “Prosopis” is from the Greek name for the burdock, however the reason for this application is as of yet unknown.
The species epithet “pubescens” (1760 Biology term - pubescent) means “covered with fine soft, short hairs or down”.
According to The Land Bird Johnson Wildflower Center the word “mesquite” is a Spanish adaptation of the Aztec name “mizquitl”.
Ethnobotany - Native American Ethnobotany; University of Michigan - Dearborn
Prosopis pubescens has been used for a multitude of purposes by southwestern United States indigenous peoples.
Apache, Chiricahua & Mescalero Food, Beverage, Bread, Dried Food and Special Food; Fruit ground and sugar added to make a thick drink and pods dried, washed, ground into flour and made into bread and fruits gathered, dried and stored in sacks and raw pods chewed and eaten as a delicacy.
Apache, Mescalero Drug, Ear Medicine; Pods soaked in water and used for earache and beans placed in ear for earache.
Cahuilla Drug, Medicinal and Fiber, Building Material; Roots and bark had medicinal value and large limbs used in construction.
Cahuilla Food, Beverage; Pod meal and water used to make a beverage and pods crushed into a pulpy juice and used to make a beverage.
Cahuilla Food, Bread & Cake and Dried Food; Pod meal and water used to make cakes and ripe pods allowed to dry or picked after fully dried and ground into meal.
Cahuilla Food, Staples; Pod meal and water used to make mush and pods used as one of the important food staples and ripe pods allowed to dry or picked after fully dried and ground into meal.
Cahuilla Other, Hunting & Fishing Item and Tools; Small limbs used to make bows and long branch made into a mescal cutter to sever agave leaves.
Hualapai Fiber, Furniture and Food, Dried Food; Roots used to make cradleboard frames and pods dried and stored for later use and as food.
Isleta Food, Unspecified; Pods chewed for the starch content and agreeable taste.
Kamia Food, Unspecified; Coiled pod used for food
Mohave Food, Beverage and Vegetable; Bean pods rotted in a pit for a month, dried, ground into a flour and used to make a drink and bean pods used for food.
Paiute Drug, Eye Medicine and Food, Unspecified; Infusion of gummy exudate on bark used as an eyewash and pounded beans used for food.
Pima Drug, Dermatological Aid and Gynecological Aid; Decoction of roots used as a wash or powdered roots applied to sores and powdered root bark or decoction used to dress wounds and infusion of roots taken for troubles with menses.
Pima Fiber, Building Material and Other, Fuel; Wood used for fence posts and wood used for fuel.
Pima Food, Beverages and Candy; Beans ground, mixed with water and made into a nourishing and sweet beverage and beans sun dried, pounded into meal, mixed with cold water and used as a drink and fresh, sugary pods chewed by children.
Pima Food, Forage and Staples; Pods and foliage eaten by grazing animals and beans pit cooked, dried, pounded and eaten as pinole and beans pit roasted for several days, dried and ground into a pinole.
Pima, Gila River Food, Snack Foods; Catkins eaten as a snack food by all age groups and sap eaten as a snack food by all age groups.
Pima, Gila River Food, Staples; Beans used to make flour and fruit used as a staple food.
Pima, Gila River Other, Season Indicator; Leaves used as a sign that planted crops would be safe from freezing weather.
Tewa Drug, Ear Medicine; Pods twisted into the ear for an earache.
See complete listing of ethno-botanical uses at Native American Ethnobotany, University of Michigan, Dearborn.
See ethno-botanical uses at Native American Ethnobotany, University of Michigan, Dearborn.