Abstracted from Pima County Regulated Flood Control District, “Regulated Riparian Habitat Mitigation Standards and Implementation Guidelines, 2010.
Lifespan, elevation, size
Seasonality; flower, fruit, berries, other
Perennial shrub/small tree
Perennial; 2500’-5000’, occurs in a variety of settings including washes, slopes, shallow caliche-lined soils and grasslands; to 15’ tall
Deciduous; very small yellow-orange flowers in spherical clusters present May-September, followed by seedpods; pairs of whitish spines on branches; nitrogen-fixer
Midstory shrubby tree occurring in a variety of habitats; often associated with velvet mesquite, desert hackberry, wolfberry, and various cacti
Nectar: eaten by insects and nectar-eating birds including verdin; Seeds: eaten by a wide variety of birds and other wildlife; Foliage: eaten by deer and jackrabbits; host plant for larval butterflies; Provides cover and nest sites for birds
Long-lived perennial; below 5000’, occurs within and along slopes, canyons, riparian bottomlands, and desert washes; shrub or small tree to 20’ tall
Small yellow flowers on cylindrical spikes bloom April–October; seedpods produced in summer to fall; semi-deciduous in winter and extreme drought; has small but sharp “cat-claw-like” thorns; nitrogen-fixer
Under- to mid-story shrub on slopes, along washes; occasionally a tree where moisture plentiful; associated with common xeroriparian species such as velvet mesquite, desert hackberry, and graythorn.
Seeds: eaten by birds and other wildlife; Nectar: attracts butterflies and other insects including ants, which in turn attract horned lizards; Shelter for a wide variety of wildlife
Celtis laevigata (Celtis reticulata)
Long-lived perennial; 1500’-6000’; occurs in moist riverbeds, and along intermittent streams,, and canyons; to 35’ tall
Deciduous; very small greenish flower blooms March-April; small reddish fruits available June to November
Midstory to overstory tree associated with Mexican elderberry, velvet ash, Fremont cottonwood, velvet mesquite, western soapberry, and Arizona walnut
Berries: eaten by a wild variety of wildlife; Provides cover and nest sites for birds including raptors
Midstory to overstory tree in variety of upland and riparian situations; commonly associated with desert wash communities including velvet mesquite, Mexican elderberry, and desert hackberry.
Nectar: consumed by hummingbirds, insects including bees (bumble bees, carpenter bees, and others), and nectar-eating birds; Insects attracted by nectar provide food for insect-eating birds; Leaves: host plant for larvae of pollinating moths; Shelter and nesting for birds and other wildlife
Arizona ash, Velvet ash
Perennial; 2000‘– 7000’; within and along streams, moist canyons and washes; to 30’ tall
Deciduous; Blooms March-April; very small yellow flowers appear before leaves
Overstory tree in riparian bottomlands; associated with Arizona walnut, netleaf hackberry, and Mexican elderberry.
Seeds: eaten by a wide variety of wildlife
Arizona black walnut
Long-lived perennial; 3000’-7000’; occurs in streams and moist canyons from desert to oak or pine forestlands; to 50’ tall
Deciduous; small greenish blooms before or during spring or summer leaf growth; produces large, edible nut.
Mid-or overstory tree in moist areas; associated with velvet ash, Mexican elderberry, Acacia spp.
Long-lived perennial; below 2500’, occurs on foothills and desert
slopes where cold air doesn’t settle; 26’to 30' tall
Purple, pink or white pea-like
flowers bloom May–June; seedpods
produced June-July; pairs of spines emerge from stems at base of leaves; nitrogen-fixer.
Mid-sized desert tree; associated
with saguaro, desert hackberry,
wolfberry, graythorn, and desert lavender
Seeds: eaten by many animals. Flowers: food for nectar-eating birds.
Leaves and twigs: browse for bighorn sheep and mule deer. Retains leaves during summer drought; important for breeding and year-round thermal shelter. Keystone species due to abundamce of wildlife that relies on it.
Parkinsonia florida (Cercidium floridum )
Perennial, moderate age; 500’–4000’, occurs in washes, valleys, and floodplains, grasslands; to 30’ tall
Bright yellow flowers bloom April–May; seedpods appear May-June; winter and drought deciduous; some spines on branches and stems; needs higher moisture levels than foothills paloverde; nitrogen-fixer
Mid- to overstory associate within a wide variety of habitats including desert, grassland and xeroriparian understory; often associated with velvet mesquite and desert hackberry
Seeds: eaten by a variety of wildlife; Nectar: used by bees and other insects and nectar-eating birds; Fallen flowers: eaten by desert tortoise and other wildlife species; Branches: provide nesting sites for numerous bird species and nighttime roosts for many wildlife species; Host plant for mistletoe which is a key food source for phainopepla;
Foothills Palo Verde, yellow palo verde
Long-lived perennial; 500-4000’; occurs throughout Sonoran desertscrub habitats and along washes and streams; slow to medium growth rate, depending on water availability; shrub or tree to 26’ tall
Large yellow flowers bloom Mar-May; seedpods mature June-July; tolerates drier condtions than blue paloverde; nitrogen-fixer.
Mid to overstory associate within a wide variety of habitats, including dersert, grassland, and xeroriparian understory; often associated with saguaro and other cacti, creosotebush, desert ironwood, and mesquite.
Seeds: eaten by birds and mammals. Flowers: provide pollen and nectar for insects, including solitary bees; also eaten by wildlife. Branches: used for nesting and roosting sites; host for mistletoe that is food of phainopepla and other birds.
Perennial; 2000’-6000’, occurs within and along streams and rocky canyons; to 80’ tall
Deciduous; inconspicuous flowers bloom March-April; flowers followed by cylindrical fruits
Overstory tree in canyons near streams; associated with Arizona walnut, Fremont cottonwood, and Goodding’s willow
Seeds: eaten by wildlife; Leaves, stems, wood: utilized by beaver;Provides habitat for wildlife including sites for cavity-nesting birds
Populus fremontii ssp. Fremontii
Long-lived perennial; 150– 6000’; occurs along streams, rivers, and
Deciduous; very small, green-yellow flowers bloom early spring (often late February in Tucson area)
Overstory tree in moist areas along streams and rivers, or elsewhere where water table is near surface; associated with Arizona sycamore, Arizona ash, Goodding’s willow, sacaton, grasslands, and canyon grape
Twigs and foliage: eaten by deer, beaver, and other mammals. Buds and catkins: eaten by
birds. Insects attracted by fragrant buds provide
additional forage for wildlife. Large size offers abundant sheltering, resting, nesting and
foraging habitat for numerous wildlife species
Perennial, moderate lifespan; below 4000’, occurs in floodplains and bottomlands; to 15-20’ tall.
Deciduous; small, yellow flowers in clusters; blooms May-August; seedpods in summer-falll; branches have spines; nitrogen-fixer.
Medium-sized tree; fixes nitrogen in soil; associates with velvet mesquite, wolfberry, graythorn, and four-winged saltbush.
Seeds and pods: eaten by a wide variety of wildlife; host plant for mistletoe, which is an important food source for phainopepla and other birds.
Long-lived perennial; 1000’-5000’; occurs in riparian floodplains; along washes, on scrubland slopes, and scattered in grasslands; generally to 30’ tall, but larger in old-growth bosques in bottomlands
Deciduous; clusters of yellow flowers bloom April-May, and again in August; seedpods are produced June-September; nitrogen-fixer
Mid- to over-story tree associated with wide variety of desert and riparian plants including saltbush, wolfberry, desert hackberry, graythorn, desert lavender, and a wide variety of grasses and forbs
Seeds, pods, bark, twigs and leaves: eaten by a wide variety of wildlife including birds, bighorn sheep, deer, antelope, coyote, and rodents; Flowers: attract 60 species of native bees, plus wasps and butterflies; Nectar and larval plant for butterflies; Nesting sites: utilized by white winged doves, mourning doves, and many other birds; Host plant for mistletoe, which is an important food source for phainopepla and other birds; Insects on plant gleaned by birds
Perennial; 4,000 – 7,000’, occurs on dry slopes, and along moist canyons in grasslands; shrub or small tree to 50’
Evergreen; small inconspicuous flowers appear in spring; acorns produced in summer
Midstory to overstory tree in variety of mid- to high-elevation settings; often along drainages in grassland settings.
Leaves and stems: browse for deer; Acorns: eaten by a variety of wildlife; Perennial cover valued by a wide variety of wildlife
Perennial; below 7000’, occurs along streams, rivers, and moist bottomlands with surface water or near-surface groundwater; to 45’ tall
Deciduous; tiny flowers in bunches bloom in spring and then release seeds that float in cottony fluff
Mid to overstory tree, often draping branches to the ground, associated with Fremont cottonwood, velvet ash, and canyon grape
Twigs and foliage: eaten by deer, beaver, and other mammals; Buds and catkins: eaten by birds, sites for insect gleaning birds; Dense cover: provides thermal shelter and cover from predators, and sheltered nest sites
Sambucus nigra ssp. Cerulea (Sambucus mexicana)
Mexican elderberry, blue elderberry
Perennial shrub/ small tree
Perennial; 1000’ – 4000’, occurs along streams, rivers, and bottomlands, and scattered across moist grasslands; shrub to small tree to 30’ tall.
Drought deciduous; yellow-white cluster of small blooms appears March-June; small, abundant berries May-October
Mid-sized tree, occasionally large, associated with Goodding’s willow, velvet mequite, netleaf hackberry, graythorn, climbing milkweed, and old man’s beard.
Berries: eaten by a wide variety of wildlife; Foliage: eaten by deer, livestock, and other mammals.
Sapindus saponaria var. drummondii
Perennial; 2,400’ – 6,000’; occurs in canyons, streams, desert grasslands, and oak woodlands; 20’ to 50’ tall
Deciduous; small white flower appears May – August, followed by yellowish berries
Multi-trunked tree occurring in riparian communities; common codominants include Arizona black walnut and velvet ash
Leaves and twigs: generally not palatable for wildlife due to the presence of poisonous saponids; Nectar: eaten by butterflies Clonal growth provides dense cover for a numerous wildlife species
Perennial shrub or subshrub
Perennial, ,1000-3000', low-growing, less than 2’ tall. Often in nearly pure stands on bajadas, plains, and mesas.
Evergreen; inconspicuous pale yellow-green flowers, fruit a small bur. Flowers February to July.
Low-growing subshrub prefers coarse, rapidly drained soils. Often associated with foothill paloverde and saguaro.
Flowers probably provide nectar and pollen for insects. Plant provides cover for small vertebrates.
Anisacanthus thurberi (Drejera thurberi)
Perennial; 2500-5500’, colonizes sandy washes, canyons, and
riparian bottomlands; upright shrub to 6’ tall
Showy red to orange flowers appear mostly in spring, but during other times when adequate moisture is present
Understory shrub, sometimes forming large clumps; often found alongside desert washes with velvet mesquite, ironwood, paloverde,
chuperosa, and desert willow
Nectar and pollen: eaten by hummingbirds and solitary bees; Leaves and twigs: browsed by
Flowers: provide nectar and pollen for bees and other insects
Eriogonum fasciculatum var. Foliolosum/ polifolium
Flat-top buckwheat, Eastern Mohave buckwheat
Perennial; 1000’-4500’; grows on hillsides and other crub-dominated uplants; to 3’ tall.
Very small white to pink persistent flowers in clusters that dry to an orangish-white color.
Sub-shrub often associated with odora and fairy duster.
Seeds: eaten by birds and other wildlife
Flowers: nectar eaten by butterflies and bees
Foliage: browsed and gleaned by mammals and some birds.
Evergreen perennial, 3000’-8000’, occurs as scattered individuals in many different plant communities; generally to 8’ tall, rarely reaching 15’
Inconspicuous tasseled flower bloom March – August; prefers partial summer shade in Tucson area
Mid-sized to large cold-hardy shrub; generally an understory component of pinyon-juniper woodlands and interior chaparral dominated by evergreen oaks and birchleaf mountain-mahogany
Foliage: browsed by deer, and other mammals; Provides good thermal and visual cover
Gossypium thurberi (Thurberia thespesioides)
Native cotton, Thurber's cotton
Perennial; 2500-5000’; occurs in canyons, wash bottoms, and on rocky slopes; shrub to 7’ tall
White to pinkish flowers bloom May-September; seed capsule with fuzzy seeds with short cottony hairs.
Occurs on rocky hillsides or in washes or canyons; frequent associates include desert honeysuckle, catclaw acacia, and burrobrush.
Leaves: host plant and larval food for the splendid royal moth
Hymenoclea monogyra (Ambrosia monogyra)
Burrobrush, single whorl burrobrush
Perennial; 1000’ – 4000’; occurs in valleys, flats, and strands with sandy soil; lanky shrub 306’ tall.
Small inconspicuous flowers appear in fall, followed by winged fruits
Understory to midstory shrub growing in sandy or disturbed soils; often associated with desert broom, seep willow, and other plants that are tolerant of frequent disturbance.
Offers cover and nesting sites for wildlife in otherwise sparsely vegetated landscapes
Perennial; below 5000’; occurs within desert washes, on dry rocky slopes, and in canyons; medium shrub to 15’ tall
Violet to blue flowers in clusters that may bloom any time of the year; very drought tolerant
Attractive medium to large shrub; often a component of creosotebush scrub communities
Flowers: important to bees, butterflies, and hummingbirds; Seeds: eaten by variety of wildlife
Red justicia, Arizona water-willow
Perennial; 1500’- 3000’, occurs within and along washes or slopes; to 3’ tall
Drought deciduous; attractive red, sometimes yellow, flowers bloom spring and fall
Semi-frost hardy small shrub; associated white-thorn acacia and a wide variety of grasses and forbs
Flowers: hummingbirds use nectar Foliage: browsed by javelina
Larrea tridentata var. tridentata
Long-lived perennial; below 4500'; inhabits dry plains and desert valleys; shrub to 10' tall
Small yellow flowers bloom Mar-April and November–December, followed by small, fuzzy white fruit
Medium to large shrub; associated species include saguaro, night-blooming cereus, paperflower, desert zinnia, and Christmas cholla; sometimes dominates extensive areas on bajadas and valley floors.
Flowers: extremely important for native insects (22 species of native bees feed only on its flowers and it supports 17 species of gall forming insects); Seeds: eaten by a variety of birds and other wildlife; Provides valuable shelter in harsh landscapes.
Lycium andersonii var. andersonii
Anderson Wolfberry, water jacket
Perennial; below 5500’; occurs in desert flats and along desert washes; 3 – 6’ tall
Drought deciduous; lavender flowers bloom February-April; fruits present late spring to summer
Alone or as understory in some areas; frequently associated with graythorn, velvet mesquite, catclaw acacia, and desert hackberry.
Fruits: eaten by birds and other wildlife
Fremont Wolfberry, Fremont's desert-thorn
Perennial; below 2500', occurs in desert valleys, and within and along washes, slopes, riparian bottomlands; shrub to 9' tall
Drought deciduous; small, lavender flowers blooms year round, but primarily Jan-Mar; can produce fruit year-round
Open areas or understory shrub in mesoriparian to xeroriparian areas; associated with saltbush, velvet mesquite, graythorn, desert hackberry, and canyon ragweed
Flowers: provides nectar and pollen for a wide variety of insects; Fruits: eaten by birds and other wildlife
Mahonia haematocarpa (Berberis haematocarpa)
Red mahonia, red barberry
Perennial; 3000’- 5000’, occurs in desert grasslands and oak woodlands; shrub to 6’ tall.
Cold-tolerant evergreen; yellow flowers in loose clusters bloom February-May, followed by red berries.
Medium shrub in full sun or as understory in oak woodlands; associated with oak, Ceanothus, juniper, sugarbush, soap tree.
Flowers: provide nectar and pollen for bees
Berries: eaten by birds and other wildlife
Foliage: browsed by deer, elk, bighorn, rabbits, and ringtail.
Perennial; 3000’- 6000’, occurs on dry slopes in the Sonoran desertscrub-Chihuhuan desertscrub transition zone; to 2’ tall
White flowers with small petals bloom April-October
Small aromatic shrub occurring on well-drained rocky hillsides; often occurring with creosotebush, desert zinnia, snakeweed, brittlebush, and
a variety of cacti; very drought-tolerant.
Provides cover for small mammals and birds
Perennial; 5000’- 7000’, flats and
forests with rich soil; to 20’ tall
Small white flowers in attractive
terminal clusters bloom June-August, followed by clusters of red berries
Large shrub standing alone or in
forest settings; requires good soil
Foliage: browsed by deer
Perennial; generally 3,000 - 6,500 feet; occurs on dry desert foothills, and in canyons and along washes and valleys; shrub to 15’ tall
Greenish-white flowers occur in dense compound spikes; hairy, red-orange fruit
Small to medium shrub in desert grasslands and scrublands; common associates include velvet mesquite, creosotebush, catclaw acacia, soaptree yucca, sideoats grama, and bush muhly
Fruit: eaten by birds and rodents; Leaves and twigs: browsed by deer and small mammals
Sugar bush, sugar sumac
Perennial shrub or small tree; 3000-5000’; occurs in desert canyons, mountains, and on slopes with chaparral; to 15’ tall.
Small cream-colored flowers appear February-March, followed by sticky, reddish fruit.
Evergreen, cold-hardy, medium to large shrub; grows alone or among chaparral or scrub oak; associated with Ceanothus, canyon hackberry, catclaw acacia, velvet mesquite, and scrub-oak associations.
Fruit: eaten by a wide variety of birds and other wildlife; evergreen foliage provides year-round shelter.
Three-leafed sumac, skunkbush sumac
Perennial; 2500’- 7500’, occurs in canyons and on moutain slopes; to 10’ tall.
Yellow flowers in dense clusters bloom March-June; red fruits mature in summer.
Deciduous, attractive shrub often as understory component of pinyon pine or oak woodlands.
Berries: eaten by small mammals and birds;
Foliage: eaten by small mammals
Bark: eaten by small mammals.
Ribes aureum var. aureum
Wax currant, golden currant
Perennial; 2600-8000’; occurs in mid- to high-elevation grasslands and mixed deciduous and coniferous woodlands; to 10’ tall
Deciduous; fragrant yellow flowers in spring and berries in summer; small to medium lanky shrub
Occurs in grasslands, coniferous forests and woodlands, and riparian and mountain shrub communities
Berries: eaten by variety of wildlife; Foliage: browed by large mammals.
Perennial; 1000’-5000’; occurs on desertscrub habitats and along washes, slopes, and rocky hillsides; shrub to 7' tall
Evergreen; inconspicuous greenish flower, male and female flowers occur on separate plants. Bloom variable from December-July; nuts appear May- July.
Small to medium shrub scattered across upland desert areas; often associated with velvet mequite, paloverde, hopbush, creosotebush, brittlebush and various cacti
Nuts: eaten by birds and a wide variety of mammals including javelina; Foliage: eaten by deer, bighorn sheep and other mammals
Yellow bells, yellow trumpet bush
Perennial; 3,000-5,500'; occurs on rocky or gravelly slopes along desert washes; shrub with upright form to 12' tall.
Deciduous; elongated, serrated leaves. Bright yellow trumpet-shaped flowers May through October.
Medium shrub of rocky slopes associated with plants of the Sonoran and Chihuahaun deserts. Often occurs with foothill paloverde and saguaro on hillsides.
Browsed by bighorn sheep and probably mule deer. Carpenter bees pirate nectar from blossoms by cutting into the base of the flower.