SPECIES: Ephedra viridis
Anderson, Michelle D. 2001. Ephedra viridis. 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/ .
No special status
Green ephedra is found extensively in the Great Basin Region, from the southwest corner of Wyoming and western Colorado, south to northern Arizona, northwestern New Mexico, and southeastern California, and north to Harney County, Oregon [19,35,38,39,41,46,47,99,104]. It has also been found in the Colorado, Little Colorado, and San Juan river drainages, and in the Rio Grande drainage south from Santa Fe into west Texas and Chihuahua, Mexico .
FRES21 Ponderosa pine
FRES30 Desert shrub
FRES33 Southwestern shrub steppe
FRES34 Chaparral-mountain shrub
FRES36 Mountain grasslands
FRES40 Desert grasslands
|Black-throated Sparrow nest in green ephedra. Photo courtesy of the PRBO Conservation Science Shrubsteppe Monitoring Program.|
Green ephedra is an important browse species for big game and domestic livestock [9,21,37,51,53,57,92,111]. It is heavily browsed by livestock and big game on winter range but only moderately or lightly browsed during other seasons [21,42,51]. Green ephedra stems and twigs are nearly all within reach of grazing animals, and can serve as winter forage because they extend above the snow [62,69,81]. Green ephedra is considered a highly important browse species in California due to its wide distribution and relative abundance . Green ephedra is also of importance to small mammals; the stem parts and sizeable seeds are favored by many small mammals [37,97]. The seeds were ranked 12-13 out of 18 and 16 out of 28 in shrub-seed preference of deer mice , and are also eaten by mountain quail .
Green ephedra is moderately palatable to all domestic livestock and many big game species, especially as winter browse [22,37,53,69]. Palatability typically decreases in the summer months . Overall palatability of green ephedra for domestic livestock and wildlife is rated as follows [22,37,69]:
|Cattle||Fair||Fair to poor||Fair|
|Sheep||Fair||Fair to poor||Fair|
|Mule deer||---||Fair to poor||Fair|
|Small nongame birds||---||---||Good|
|Upland game birds||---||---||Good|
Green ephedra has fair energy and protein value . Specific nutrient values vary according to plant part and seasonal development. Mineral content was examined in detail in a study at the Nevada Test Site , and the results are as follows:
percent dry weight
ppm of dry weight
Nutritional value is fairly high in the winter months relative to dormant grasses .
Green ephedra is highly toxic to both domestic sheep and cows during gestation, even at low doses. It causes ruminal impaction, diarrhea, vomiting, fecal mucus, anorexia, and in some cases death. However, this study reported no negative effects on offspring, either lambs or calves. Green ephedra plant tissue contains ephedrine, pseudoephedrine, norephedrine, N-methyl pseudoephedrine, norpseudoephedrine, N-mehtyl pseudoephedrine, and a high tannin content .
Green ephedra provides some cover for small birds and mammals. The value of green ephedra as cover for wildlife is rated as follows :
|Small nongame birds||Poor||Good|
|Upland game birds||---||Fair|
Green ephedra is listed as a successful shrub for restoring western rangeland communities  and can be used to rehabilitate disturbed lands [16,25,29,30,40,66]. It also has value for reducing soil erosion on both clay and sandy soils [65,92]. Green ephedra establishes readily through direct seeding, transplants, and stem cuttings [67,92]. Container-stock green ephedra has potential value for rehabilitation of arid road cuts, with more than 80% of plants surviving for at least 2 years on both north and south exposures. However, major plant losses occurred on the southern exposures during the winter . Container stock also showed high survival along roadsides in the Mojave Desert . Green ephedra also shows promise for reclamation use of surface-mined lands and coal fields in the pinyon-juniper shrubland of Utah [29,30]. Seedlings require protection from trampling by livestock until they are well established .
Green ephedra seed is being used to restore disturbed areas to native vegetation, though in 1996 the amount of seed sold (1605 lbs.) by Utah distributors was relatively small compared to sagebrush and saltbrush species [59,82]. Green ephedra has been listed as a species selected for forage, cover, productivity, adaptability and ease of establishment for reseeding degraded rangeland in the Intermountain Region of the United States , but green ephedra is very site-specific. When seeded on marginal or poor sites, green ephedra plants are less vigorous and fail to spread by natural seed; the young plants grow slowly and do not survive if subjected to herbaceous competition . Green ephedra is highly sensitive to soil salinity; on soil with conductivity of 0.20 mmhos/cm plants displayed normal, healthy growth and color, but on soil with conductivity of 6.92-25.8 mmhos/cm, all green ephedra plants died within the first three months . On studies of disturbed sites, green ephedra was found to be poorly suited for mixed-seed revegetation due to its inability to compete with grass and legume seed mixtures [29,36].
Germination rates of seed be improved by a period of afterripening ; fresher seed lots had germination rates of 28% over a 28 day period, whereas older seed lots experienced full germination over 28 days . In laboratory tests, optimum germination of seeds was achieved with alternating temperature regimes with 16 hour cold periods of 35.6 to 41 degrees Fahrenheit (2-5°C) and 8 hour warm periods of 59 to 77 degrees Fahrenheit (15-25°C) .
The stems of green ephedra were traditionally brewed by Native Americans to make a nonmedicinal beverage [111,112] as well as a medicinal tea considered to be a remedy for a backache [46,92,112]. Native Americans also made flour and a coffeelike beverage from the seeds . Ephedra species also provided Native Americans with good charcoal for tatooing . Green ephedra can be used for xeriscaping projects , and has been widely used as a landscape species for roadsides, mine dumps, and recreational sites. It is valuable for its vivid green color in an often dull gray sagebrush environment .
Green ephedra transplants as well as seeds have been planted with success [16,52]. Container stock has experienced 100% survival on both irrigated and non-irrigated sites after two years, with 67% of irrigated stock and 100% of non-irrigated stock surviving after 5 years . Successful seeding requires a shallow planting depth of 0.39 to 0.79 inches (1-2 cm) .
Mixed results have been found regarding green ephedra's reponse to grazing. It is described as a constituent of communities that are productive for grazing in Nevada , and has been found in greater abundance on grazed sites than on ungrazed sites in Canyonlands National Park, Utah . A limited increase in the presence of green ephedra after grazing has been reported in Utah [47,65], while others found the shrub decreasing or absent on heavily grazed and recovering sites in Arizona and Utah [43,65,81]. Generally, green ephedra is found on ungrazed sites as well as sites subject to light or moderate grazing pressure , and green ephedra found in Utah's Pine Valley pinyon-juniper woodlands has demonstrated an increase in live plant cover following a reduction in grazing .
Green ephedra typically reaches 0.75 to 5 feet (.25 to 1.5 m) in height [18,65,69,99], though it has been reported to grow up to 6 feet (2 m) tall and 10 feet (3 m) wide . It has numerous parallel stems that point upward resembling a broom, with branchlets clustered around nodes. Stems are generally less than 0.12 inch (3 mm) in diameter [18,19,99] and are bright green, with thicker growth developing gray, shreddy bark [18,99]. The jointed branches have small, scale-like, inconspicuous leaves growing opposite on the stem joints [65,69,111].
The fragile [5,75], deep-rooting system of green ephedra consists of several taproots extending almost straight down from the shrub's base, spreading only slightly and subdividing at intervals into somewhat smaller roots .
Green ephedra is dioecious , producing nut-like seeds partly or entirely enclosed in large bracts that form a cone structure . It has been reported displaying spatial segregation of male and female plants [12,76].
Green ephedra regenerates from seed and by sprouting from the roots and woody crown. Green ephedra is readily established from seed [49,52,96], though seed production is erratic under natural conditions, with an abundant seed crop occurring very infrequently . Seeds are pollinated by wind [58,76], and seed dispersal occurs via small mammals . Seeds undergo a period of dormancy, which can be broken by a 4-week prechill . Constant warm temperatures decrease germination rates, suggesting green ephedra responds to the stratification effect of cold periods . Seed remains viable for 5 years stored dry at 70 degrees Fahrenheit (21 °C) . Seed germination rates have not been found to drop significantly over 15 years with temperatures ranging from negative 21 to 101 degrees Fahrenheit (-29.9-38.3 °C) . After 15 years stored in an open unheated and uncooled warehouse, germination has been found to decrease significantly, from 88% at 15 years to 24% at 20 years (p<0.05). After 25 years, germination rates dropped to 2% .
Vegetative regeneration: Green ephedra has also been identified as a resprouting species following disturbance. It sprouts from root tissue [6,7,26] and woody crown tissue [97,109]. Shrub clumps over an extensive area may represent individuals or multiple clones . Stem cuttings were found to root readily under greenhouse conditions .
Green ephedra seedling vigor is described as weak. Initial growth is often slow, with seedlings reaching 2 feet (0.6 m) in height after 5 to 10 years of growth . Many multistemmed plants appear to be single individuals, but are actually 2 or more genetically distinct plants which originated from a common rodent cache .
Green ephedra is found on dry, rocky, open sites in valleys and washes, and on slopes, alluvial fans, mesas, and foothills [4,18,24,41,61,65,107,111]. It is typically found at elevations ranging from 3,000 to 7,500 feet (914-2,286 m) [1,13,14,48,55,65,80,107] though it has been reported at elevations up to 10,000 feet (3,048 m) in California and Utah [80,104]. Green ephedra has been reported growing on north [1,31,61], south , southwest, and west aspects . Average precipitation on sites supporting green ephedra ranges from 8 to 15 inches (200-380 mm) [6,48], and green ephedra has been found to require 6 to 10 inches (150-250 mm) annual precipitation .
Green ephedra grows primarily on sandy, gravelly or rocky, well-drained, undeveloped soils [13,14,20,47,74,99]. Soil parent material is often granitic [1,49,90,106]. Green ephedra grows well on shallow, medium or deep soils [55,93,99] and is tolerant of calcareous, weakly saline, moderately alkaline, slightly sodic soils [6,34,71,87,99]. It is found on silty loam soils with low infiltration rates , but it is intolerant of wet, poorly drained sites .
The following sagebrush site characteristics are examples of sites where green ephedra occurs :
|basin big sagebrush||mountain big sagebrush||Wyoming big sagebrush||black sagebrush|
|annual precipitation||13+ inches (330 mm)||12-17 inches (300-430 mm)||
|soil||deep, well-drained soil||deep, well drained soil, moisture available most of the growing season||moderately deep to shallow soil, well-drained, gravelly||well drained soil, rocky to gravelly, carbonates present at the soil surface|
|location||valleys, foothills||mountain brush, pinyon-juniper communities||xeric valleys, foothills, gravelly outcrops, high plains, alluvial fans||lower foothills, valley edges and bottoms, alluvial fans, rocky ridges and saddles at high elevations|
Cover values for green ephedra vary based on site characteristics; in Arizona, washes with active soil and gravel deposition had a green ephedra cover value of .5%, while slopes above the washes that had shallow soils and little soil development had a cover value of 1.8%. The transition zone with stabilized soil formed from wash deposits but with no active soil movement had the highest cover value, 3.2% .
Though not usually reported as a species of major importance, as a plant community component green ephedra occurs in early, mid-, and late successional stages [48,106]. It grows vigorously in full sun and more slowly in partial shade . Green ephedra has been reported as having a cover value of 0% in the first stage (grass-forb) of succession in a pinyon-juniper woodland, 0.8% in the second stage (shrub-tree), and 0.1% in both the third and fourth stages (tree-shrub and tree, respectively) . It appears in both shrub dominated and tree dominated pinyon-juniper and sagebrush sites in the Great Basin . On Spy Mesa in Arizona, green ephedra was identified in both grass-dominated areas (early succession) and shrub-dominated (mid-succession) areas of a pinyon-juniper woodland . In a pinyon-juniper woodland where no successional change occurred over 23 years, green ephedra plants and clumps demonstrated variable increases and decreases in size , and green ephedra was present in a nearly mature pinyon-juniper woodland at less than 1% cover . Green ephedra is considered weakly competitive due to its slow growth rate .
Vegetative growth of green ephedra occurs during the cool season . Seed development begins in the spring and seeds mature by late summer [99,111]. Seed maturation dates have been established at July 15 to September 1 . Green ephedra seed germination occurs following a minimum 4-week chill to break seed dormancy .
Green ephedra generally sprouts vigorously from the roots or woody root crown after fire [6,48,99,109] and rapidly produces aboveground biomass from surviving meristematic tissue . Green ephedra has also been documented in southern California as nonsprouting postfire . It is capable of reestablishing disturbed areas through seed , though no significant difference was found between its occurrence on seeded versus nonseeded postburn sites in a Great Basin pinyon-juniper woodland . Fires are relatively uncommon in some green ephedra communities due to insufficient fuels . Green ephedra has been found in plant communities with a wide range of fire return intervals, and has been found in ecosystems following large, stand replacing fires as well as small, patchy, erratic fires . Green ephedra establishes early after fire but with relatively low occurrence compared to mid- and late successional stages .
Fire regimes for plant communities and ecosystems in which green ephedra occurs are summarized below. Find further fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find Fire Regimes".
|Community or Ecosystem||Dominant Species||Fire Return Interval Range (years)|
|sagebrush steppe||Artemisia tridentata/Pseudoroegneria spicata||20-70 |
|basin big sagebrush||Artemisia tridentata var. tridentata||12-43 |
|mountain big sagebrush||Artemisia tridentata var. vaseyana||5-15 |
|Wyoming big sagebrush||Artemisia tridentata var. wyomingensis||10-70 (40)** [95,110]|
|saltbush-greasewood||Atriplex confertifolia-Sarcobatus vermiculatus||< 35 to < 100|
|desert grasslands||Bouteloua eriopoda and/or Pleuraphis mutica||5-100|
|grama-galleta steppe||Bouteloua gracilis-Pleuraphis jamesii||< 35 to < 100|
|California montane chaparral||Ceanothus and/or Arctostaphylos spp.||50-100 |
|curlleaf mountain-mahogany*||Cercocarpus ledifolius||13-1000 [2,72]|
|mountain-mahogany-Gambel oak scrub||Cercocarpus ledifolius-Quercus gambelii||< 35 to < 100|
|blackbrush||Coleogyne ramosissima||< 35 to < 100|
|western juniper||Juniperus occidentalis||20-70|
|creosotebush||Larrea tridentata||< 35 to < 100|
|pinyon-juniper||Pinus-Juniperus spp.||< 35|
|Colorado pinyon||Pinus edulis||10-49|
|Jeffrey pine||Pinus jeffreyi||5-30|
|Arizona pine||Pinus ponderosa var. arizonica||2-10|
|galleta-threeawn shrubsteppe||Pleuraphis jamesii-Aristida purpurea||< 35 to < 100 |
Small shrub, adventitious bud/root crown
Ground residual colonizer (on-site, initial community)
Green ephedra has been reported to survive range fires . It may also be top-killed by fire in both shrub and grass communities and pinyon-juniper woodlands, reestablishing on-site from both seed and surviving meristematic tissue [7,26,48,99]. Green ephedra has also been described as nonsprouting after fire in chaparral ecosystems of southern California.
Green ephedra sometimes sprouts vigorously from the roots or woody root crown following fire [107,109]. On a pinyon-juniper woodland site, it was found to be a dominant postfire resprouter and persisted on burns after more than 78 years . After a Nevada wildfire in a late seral big sagebrush community, virtually all green ephedra plants produced new stems . Though green ephedra also reestablishes from seed on-site , this same sagebrush community had no green ephedra seedling establishment up to 4 years postburn .
After late July-early August wildfires in western Nevada, green ephedra sprouted vigorously from surviving roots and root crowns. Green ephedra density and sprouting response in the next growing season was as follows :
|Density (10 m2)||% Sprouting|
California chaparral communities historically experienced numerous, erratically spreading, small fires resulting in a highly fragmented mosaic. As a result of fire suppression, extensive stands of mature chaparral exist in fewer and larger patches. The effects of these community changes on green ephedra have not been evaluated, though it was found to exist as a community constituent under both fire regimes .
An evaluation of plant response to various burning, grazing, and herbicide activities was conducted in a big sagebrush community in Nevada . The response of green ephedra to these activities is described in the table below. Green ephedra had greatest cover on sites burned more than 10 years before and being moderately grazed; cover was lowest on unburned sites with heavy grazing.
|Burned, currently moderate grazing||Unburned, currently grazed||2,4D treatment, currently grazed (~2 yrs. post treatment)||2,4D and picloram, ungrazed (~2 yrs. post treatment)||2,4D, heavy grazing (10 yrs. post treatment)|
|<10 years postburn||>10 years postburn||Heavy||Moderate||Light||Heavy||Moderate||Light|
|200 plants/ha||300 plants/ha||0 plants/ha||100 plants/ha||200 plants/ha||100 plants/ha||100 plants/ha||200 plants/ha||200 plants/ha||200 plants/ha|
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