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Species Review

Descurainia sophia, herb sophia

Written
May, 2003
Contributors
Janet Howard - 1st Author

Howard, Janet L. 2003. Descurainia sophia, herb sophia. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://research.fs.usda.gov/feis/species-reviews/dessop

DOI
10.2737/feis-species-review-dessop

AbbreviationCommon NameScientific NameClassificationStatus
Plants
DESSOPherb sophiaDescurainia sophiaLife Form: Plants/Forb
Kingdom: Plantae
Class: Dicot
Order: Capparales
Family: Brassicaceae
Genus: Descurainia
Fed. Protected: No
Nativity: Nonnative
Invasiveness: Invasive

Photo of a cluster of small yellow flowers at the end of a green stem, with a bright blue sky and brown hills in the background.
Photo Credit
Photo by Tyler M., iNaturalist.org, no rights reserved.

Herb sophia flowers.

Taxonomy

The scientific name of herb sophia is Descurainia sophia (L.) Webb ex Prantl (Brassicaceae) [32,48,51,64,69,90,106,130,133,142,145,147].

Synonyms

  • None

Other Common Names

flixweed tansymustard

General Distribution

Herb sophia is native to Europe and northern Africa [133]. It probably arrived in North America in the mid-1800s as an impurity in crop seed, and was widespread by the 1920s [103]. It now occurs in 48 states, excluding Alabama and Florida [72]. Its distribution extends south to Baja California, and as far north as 70° N latitude in Greenland, Alaska, and Canada. It occurs throughout Canada except Labrador and eastern Nunavut [69,72,133,147]. Plants database provides a distributional map of herb sophia in the United States and Canada. Herb sophia is also introduced in South America, Asia, southern Africa, and New Zealand [69,88].

States and Provinces

  • United States: AK AZ AR CA CO CT DE GA HI ID IL IN IA KS KY LA ME MD MA MI MN MS MO MT NE NV NH NJ NM NY NC ND OH OK OR PA RI SC SD TN TX UT VT VA WA WV WI WY DC PR VI
  • Canada: AB BC MB NB NF NT NS NU ON PE PQ SK YK
  • Mexico: B.C.N.

Site Characteristics

Herb sophia occurs in open-canopy, disturbed sites. It is particularly common in washes and on roadsides, railroad rights-of-way, waste grounds, old fields, and early seral burns [35,64,70,100,101,110,142,151]. It grows in a variety of mineral soils including loam, silty clay [36], and sand, where it is most common. It tolerates dry soil, but is not salt tolerant [56,121]. In salt-desert shrubland of central Utah, herb sophia occurred only on plots with < 3,000 ppm soluble salts and < 12% soil moisture [121].

Elevation

Elevational ranges of herb sophia as reported by state
StateElevation range
California<8,530 ft (<2,600 m) [64]
Colorado4,000-8,000 ft (1,200-2,400 m) [57]
New Mexico4,000-8,000 ft [82]
Nevada2,220-9,000 ft (680-2,700 m) [73]
Utah2,300-8,050 ft (700-2,450 m) [145]

Plant Communities

Herb sophia grows in a broad spectrum of environments ranging from cold desert, tundra, taiga, alpine, and subalpine ecosystems to hot desert and dry-tropical Hawaiian ecosystems [72].

Photo of a dense cluster of green plants, dominated by a fine-leaved plant with small yellow flowers.
Photo Credit
Photo by Jared Lincenberg, iNaturalist.org, some rights reserved.

Herb sophia growing in Golden, Colorado (CC BY 4.0).

Herb sophia is ecologically important in most North American desert ecosystems. In Great Basin Desert communities of east-central Nevada, it showed 25-40% frequency in big sagebrush (Artemisia tridentata) communities and 5-66% frequency in singleleaf pinyon-Utah juniper (Pinus monophylla-Juniperus osteosperma) communities [18]. On the Desert Tortoise Research Natural Area in the Mojave Desert, southern California, herb sophia associates with creosotebush (Larrea tridentata), white bursage (Ambrosia dumosa), and other annuals, the most common being cutleaf filaree (Erodium cicutarium), red brome (Bromus madritensis ssp. rubens), and Mediterranean grass (Schismus spp.) [20].

A few vegetation classifications describe plant communities dominated by herb sophia. A herb sophia-Russian-thistle (Salsola kali) community occurs in Lava Beds National Monument, California, on land with a history of extreme disturbance: 1st by lake drainage, then by cultivation of the lakebed [36]. In east-central Nevada, herb sophia communities occur on highly disturbed winterfat (Krascheninnikovia lanata) habitat types. Halogeton (Halogeton glomerata) codominates, and winterfat is present in trace amounts [18].

Botanical Description

Photo of a small green plant with finely divided leaves and small yellow flowers, growing among rocks.
Photo Credit
Photo by Craig Martin, iNaturalist.org, no rights reserved.

Herb sophia plant in Santa Fe County, New Mexico.

The following description of herb sophia provides characteristics that may be relevant to fire ecology, and is not meant for identification. Keys for identification are available (e.g. [32,48,51,64,106]).

Herb sophia is an exotic, cool-season annual or biennial. It is the type species for the genus [51,64,88,130,134]. The single, 6- to 31-inch-long (15-80 cm) stem is coarse, with basal and cauline leaves. Cauline leaves have a large amount of surface area, being 2 or 3 times pinnately divided. The inflorescence is a raceme of bisexual flowers. The fruit is a 1 × 10- to 71-mm-long silique bearing 10 to 20 small (10-25 mm long), seeds [32,49,51,64,96,106,145]. Tansymustard (Descurainia spp.) fruits and seeds do not have specialized appendages for dispersal [74,76]. Tansymustards have a short taproot [29,153].

Stand structure of herb sophia-dominated communities is sparse immediately after disturbance. Herb sophia stands often become dense and crowded within a few postdisturbance years, and thin as succession advances [16]. For further information on herb sophia's role in succession, see Successional Status below.

Raunkiaer Life Form

  • Therophyte [107]

Seasonal Development

Germination usually begins in winter or early spring [134,135], depending upon latitude and elevation. Herb sophia is 1 of the 1st plants to appear in spring. After the cotyledon stage, the seedling forms a rosette of basal leaves, then grows the stem and cauline leaves [64]. Fall-germinating seeds overwinter as rosettes [16]. In the United States, herb sophia 1st flowers in the Southeast [106,130]. 

Timing of herb sophia phenological events by region.
RegionEventPeriod
SoutheastanthesisFeb.–Aug. [106,130]
SouthwestanthesisMarch–July [73]
Pacific NorthwestanthesisMarch–July [67]
NortheastanthesisMay–July [48]
Great Plains, northernanthesisMid-June–late July [49,96]
Great Plains, southernanthesisMarch–Sept. [32]
Great LakesanthesisJune–Aug. [90]
fruits ripenJune–early Sept. [96]

Regeneration Processes

Herb sophia reproduces solely from seed [114,126].

Pollination and Breeding System

Pollination is insect-mediated. The sepals contain nectaries that attract insect pollinators [63]. Mustards (Brassicaceae) are cross-pollinated. Selfing also occurs [63].

Seed Production

Herb sophia produces an average of 75-650 seeds per plant [124]. A large plant may produce upwards of 700,000 seeds [114].

Seed Dispersal

Wind, water, machinery, and animals transport herb sophia seed, although most seed falls near the parent plant [114]. Animals disperse tansymustard seeds when the mucilaginous seedcoat sticks to feathers or fur [155].

Seed Banking

Herb sophia builds up a soil seed bank [2,5,39,149]. The seed bank can be large: Stevens [126] documented a herb sophia seed population of 704,582/m2 in North Dakota soil. Herb sophia was an important component of the soil seed pool (all spp.) in big sagebrush-green rabbitbrush (Chrysothamnus viscidiflorus) of southwestern Wyoming [30]. On the Nevada Test Site near Las Vegas, herb sophia was the 2nd most common species to emerge on irrigated and unirrigated test plots; red brome was most common [149]. Long-term viability of herb sophia seed is unknown, but the seed is reported to remain viable for "considerable periods in the soil" [114]. Buried flixweed seed remained viable at least 4 years in Fairbanks, Alaska. Seed viability generally dropped with years of soil storage [26]:

Germination rate of soil-stored flixweed seed over time [26].
0 Years2.7 Years3.7 Years4.7 Years
67%28%36%10%

Germination

Herb sophia shows good germination [27], with a mean rate of about 70% [114]. Seed collected in Alberta showed 75% germination after cold storage/stratification. In another aspect of the study, some seeds from the lot survived digestion by ruminant grazers or short-term silage. Three percent of ingested seed germinated after 1 day in a cow's rumen, and seed stored in the bottom of a barley (Hordeum vulgare)-filled silo for 8 weeks showed 2% germination [19].

Overhead photo of a plant rosette with a few stems covered with finely divided leaves, growing on mostly bare ground.
Photo Credit
Photo by Joseph M. DiTomaso, University of California - Davis, Bugwood.org.

Herb sophia seedling.

Herb sophia is adapted to establishing in dry environments. The seedcoat of tansymustards forms a thin layer of mucilage after wetting [64,155]; the mucilaginous layer helps germinating seeds retain water [155].

Seedling Establishment and Growth

The taproot exploits moisture in the upper soil layer [29,152,153], and uncrowded plants develop rapidly. Plants may develop numerous leaves and up to 15 lateral, fruit-bearing branches at maturity [16].

Vegetative Reproduction and Regeneration

Herb sophia does not reproduce or regenerate vegetatively.

Successional Status

Herb sophia occurs in early seral communities. It is common on disturbed ground [36,39,60,61,95,128,136]. For example, in a big sagebrush community in northwestern Colorado, herb sophia appeared the 1st year after bulldozing, showing mean productivity of 1 g/m2. Productivity peaked at postdisturbance year 2, and declined for the next 5 years. Herb sophia was present in only trace amounts on undisturbed control plots. It showed the same pattern of succession on plots that were fertilized with nitrogen after bulldozing, except productivity was greater on fertilized plots compared to unfertilized plots (15 vs. 5 g/m2 at postdisturbance year 2) [84]. On oilfields of Prudhoe Bay, Alaska, herb sophia was among the most important forbs 5 to 8 years after exploratory drilling [83]. Herb sophia is nonmycorrhizal [98]; thus, it is able to pioneer on sterile sites or on sites undergoing primary succession [3,17].

A common pattern of succession in disturbed sagebrush steppe begins with Russian-thistle. Herb sophia, western tansymustard (Descurainia pinnata), and/or tall tumblemustard (Sisymbrium altissimum) soon follow successionally. Russian-thistle may in turn reinvade the mustard stands with grazing disturbance, but more commonly, the mustards are succeeded by cheatgrass (Bromus tectorum) [66,101,152]. In desert environments, cheatgrass usually requires litter for successful germination and establishment. Dried skeletons of herb sophia and other annual forbs may facilitate cheatgrass establishment by providing litter [37,38]. For information on the interactions of herb sophia and cheatgrass, see Fire Management Considerations and the FEIS review on cheatgrass.

Herb sophia is uncommon to absent in late seres [115]. In central Saskatchewan, herb sophia occurred in fallow and recently harvested wheat (Triticum aestivum) fields. It was not present, or found in seed bank soil samples, of adjacent undisturbed shortbristle need-and-thread-western wheatgrass (Hesperostipa curtiseta-Pascopyrum smithii) prairie [5]. On strip-mined sites in south-central Alaska, herb sophia volunteered on revegetated reclamation sites, but was absent by posttreatment year 10 [34]. Herb sophia is most likely to persist in communities that retain unlittered soil and open canopies into late succession. In singleleaf pinyon-Colorado pinyon (Pinus edulis)-Utah juniper communities of west-central Utah, where litter build-up can be slow, herb sophia occurred on burns in early to late stages of succession (3-100+ years), but was most common on new burns [13]. On mixed-grass prairies in Wyoming, which are likely to build up litter quickly, herb sophia was common for ~10 years postdisturbance, then became increasing scarce [115].

Herb sophia and the native western tansymustard are apparently equally invasive, and fill similar ecological niches [89].

Immediate Fire Effects

While in the rosette stage, herb sophia may be top-killed by fire. If the root crown is not damaged, herb sophia rosettes can sprout new basal leaves from the root crown. As an annual with a single stem, herb sophia lacks adaptations for regrowth once it has bolted [2,39], and plants burned after the rosette stage are killed. Research on fire's impact to the seed bank is lacking as of this writing (2003), but it appears that fire has little effect on herb sophia seed populations. Herb sophia has tiny seeds [32,51,64,106] that easily fall into fire-safe microsites such as soil crevices. While fire is likely to kill some seed, its overall effect to the herb sophia seed bank is probably negligible.

Postfire Regeneration Strategy

  • Ground residual colonizer (on-site, initial community)
  • Initial off-site colonizer (off-site, initial community) [127]

Fire Adaptations

Herb sophia establishes from soil-stored seed after fire [2,39]. Animal, wind, or machinery transport from off-site may provide additional, minor sources of seed [155] or introduce herb sophia to burns where it is not already present in the soil seed bank. Fire creates conditions favorable for herb sophia establishment (bare soil, open canopy, reduced growth interference) [16,101]. As a shade-intolerant, invasive species, herb sophia thrives in the early postfire environment [151].

Plant Response to Fire

Herb sophia establishes from soil-stored seed after fire [2,39], reaching greatest density in early postfire succession [13,95]. Banked seed usually germinates and establishes in postfire years 1 or 2. The postfire population increases rapidly, and by postfire years 2 to 4, localized, dense stands of herb sophia may form [13,39]. In pinyon-juniper (Pinus-Juniperus spp.) stands of Nevada and Utah, for example, herb sophia appears in early successional years along with other annual herbs [13,102]. Herb sophia density decreases as postfire succession continues, although herb sophia may persist in low numbers in late-successional burns that have retained an open canopy [13,14].

In big sagebrush communities that have experienced fire or other disturbance that removes the sagebrush, herb sophia commonly dominates or is an important component of the initial postfire community. Along with herb sophia, Russian-thistle, western tansymustard, and/or tall tumblemustard form the initial plant community, which is dominated by annuals. Cheatgrass may be part of the initial community in mesic environments. On dry sites, it may follow successionally soon after the annual forbs [101], when litter has created a seedbed favorable for cheatgrass germination [37,38].

Although fire creates an open canopy and bare mineral soil, which favors herb sophia establishment, herb sophia is not an obligate "fire follower." Any area with bare ground, open sunlight, and a seed source is vulnerable to herb sophia invasion [60,61].

Grazing: Few studies have focused on the interactive effects of fire and grazing on herb sophia. One study suggests that fire and grazing may reduce postfire cover of annuals more than fire alone, but the results are inconclusive for herb sophia. Russian-thistle, herb sophia, and prickly-lettuce (Lactuca serriola) were the 3 most important annual forbs, respectively, on a Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis)-green rabbitbrush burn in central Utah. The 3 annual forbs showed greatest coverage on ungrazed, burned sites (~50%), slightly less cover on grazed, burned sites (~45%), and least cover on grazed, unburned sites (~27%). (Data are pooled means for the 3 forbs over 12 postfire years) [146]. Further studies are needed to understand how combined fire and grazing affect herb sophia.

Herb sophia may invade after restoration treatments [34], including postfire restoration. It was the most abundant exotic forb species 1 and 2 years after prescribed burning and glyphosate treatment to control smooth brome (Bromus inermis) on native rough fescue (Festuca altaica) prairie in Saskatchewan. Herb sophia numbers were similar on smooth brome-infested and native prairie plots, which were also treated with fire and herbicide [53].

Burning may not increase postfire cover of herb sophia. In his classic study of postfire succession of herb sophia and other exotics in big sagebrush, Piemeisel [100] wrote "the mere statement that a field has been burned is not sufficient information to foretell what the effect will be on the succeeding plant cover." For example, a Gambel oak/common snowberry (Symphoricarpos albus) community in Utah was chained and burned to increase forage production for cattle and elk. Two years after treatment, herb sophia cover showed little change (± 1%) compared to pretreatment levels [79]. Piemesel [100] stated that site grazing history, postfire weather patterns, and level of postfire cheatgrass cover will affect cover and relative abundance of herb sophia and other early successional forbs.

The FEIS Research Project Summary Nonnative annual grass fuels and fire in California's Mojave Desert provides information on prescribed fire and postfire response of plant community species including herb sophia.

Fire Regimes

Introduced species can alter the rate of spread of fire, the probability of occurrence of fire, and the intensity of fire in an ecosystem [31]. Herb sophia has multiple, finely divided leaves [32,51,64,106] and tends to form dense stands that are dead and dry by the fire season [16]; hence, it provides a source of fine surface fuels that can spread fire. If herb sophia stands do not burn, they provide litter that favors establishment of species, including cheatgrass, which are more sensitive to desiccation as germinants and seedlings than herb sophia [37,38].

Herb sophia was absent or unimportant in fire-prone ecosystems when historic fire regimes were functional; however, western and other tansymustards were present. Herb sophia and western tansymustard are morphologically and ecologically similar [89], and herb sophia is filling or sharing the ecological niche of western tansymustard as an initial colonizer and early seral species on burns. The role of both species in facilitating establishment of other weedy species in dry environments by providing litter (and subsequently, more mesic conditions for germination and seedling growth of other species including cheatgrass) needs further investigation. There may be subtle differences in the effectiveness of the 2 species in facilitating postdisturbance succession; this also bears investigation, particularly in areas vulnerable to cheatgrass invasion.

Because herb sophia is widespread, it is difficult to exclude many ecosystems as potential hosts of herb sophia plants or populations. The following table provides some fire return intervals for plant communities where herb sophia may be important. For additional fire regime information, search FEIS for this species by entering the species name on the Advanced Search page and selecting “Fire Regime” as the publication type.

Community or EcosystemDominant SpeciesFire Return Interval Range (years)
silver fir-Douglas-firAbies amabilis-Pseudotsuga menziesii var. menziesii> 200
grand firA. grandis35-200 [8]
maple-beech-birchAcer-Fagus-Betula> 1000
silver maple-American elmA. saccharinum-Ulmus americana< 35 to 200
sugar mapleA. saccharum> 1,000
sugar maple-basswoodA. saccharum-Tilia americana> 1,000 [144]
California chaparralAdenostoma and/or Arctostaphylos spp.< 35 to < 100 [97]
bluestem prairieAndropogon gerardii var. gerardii-Schizachyrium scoparium< 10 [77,97]
Nebraska sandhills prairieA. gerardii var. paucipilus-S. scoparium< 10
bluestem-Sacahuista prairieA. littoralis-Spartina spartinae< 10 [97]
silver sagebrush steppeArtemisia cana5-45 [62,104,150]
sagebrush steppeA. tridentata/Pseudoroegneria spicata20-70 [97]
basin big sagebrushA. tridentata var. tridentata12-43 [116]
mountain big sagebrushA. tridentata var. vaseyana15-40 [9,23,87]
Wyoming big sagebrushA. tridentata var. wyomingensis10-70 (40**) [141,156]
coastal sagebrushA. californica< 35 to < 100
saltbush-greasewoodAtriplex confertifolia-Sarcobatus vermiculatus< 35 to < 100
desert grasslandsBouteloua eriopoda and/or Pleuraphis mutica5-100 [97]
plains grasslandsBouteloua spp.< 35 [97,150]
blue grama-needle-and-thread grass-western wheatgrassB. gracilis-Hesperostipa comata-Pascopyrum smithii< 35 [97,113,150]
blue grama-buffalo grassB. gracilis-Buchloe dactyloides< 35 [97,150]
grama-galleta steppeBouteloua gracilis-Pleuraphis jamesii< 35 to < 100
blue grama-tobosa prairieB. gracilis-P. mutica< 35 to < 100
cheatgrassBromus tectorum< 10
California montane chaparralCeanothus and/or Arctostaphylos spp.50-100 [97]
sugarberry-America elm-green ashCeltis laevigata-Ulmus americana-Fraxinus pennsylvanica< 35 to 200 [144]
paloverde-cactus shrubCercidium microphyllum/Opuntia spp.< 35 to < 100 [97]
curlleaf mountain-mahogany*Cercocarpus ledifolius13-1000 [11,118]
mountain-mahogany-Gambel oak scrubC. ledifolius-Quercus gambelii< 35 to < 100 [97]
Atlantic white-cedarChamaecyparis thyoides35 to > 200 [144]
blackbrushColeogyne ramosissima< 35 to < 100
Arizona cypressCupressus arizonica< 35 to 200
northern cordgrass prairieDistichlis spicata-Spartina spp.1-3 [97]
beech-sugar mapleFagus spp.-Acer saccharum> 1000 [144]
California steppeFestuca-Danthonia spp.< 35 [97,129]
black ashFraxinus nigra< 35 to 200 [144]
juniper-oak savannaJuniperus ashei-Quercus virginiana< 35
Ashe juniperJ. ashei< 35
western juniperJ. occidentalis20-70
Rocky Mountain juniperJ. scopulorum< 35
cedar gladesJ. virginiana3-7
tamarackLarix laricina35-200 [97]
western larchL. occidentalis25-100 [8]
creosotebushLarrea tridentata< 35 to < 100
Ceniza shrubL. tridentata-Leucophyllum frutescens-Prosopis glandulosa< 35 [97]
yellow-poplarLiriodendron tulipifera< 35 [144]
wheatgrass plains grasslandsPascopyrum smithii< 5-47+ [97,104,150]
Great Lakes spruce-firPicea-Abies spp.35 to > 200
northeastern spruce-firPicea-Abies spp.35-200 [33]
southeastern spruce-firPicea-Abies spp.35 to > 200 [144]
Engelmann spruce-subalpine firP. engelmannii-A. lasiocarpa35 to > 200 [8]
black spruceP. mariana35-200 [33]
blue spruce*P. pungens35-200 [8]
red spruce*P. rubens35-200 [33]
pine-cypress forestPinus-Cupressus spp.< 35 to 200 [8]
pinyon-juniperPinus-Juniperus spp.< 35 [97]
whitebark pine*P. albicaulis50-200 [1,6]
jack pineP. banksiana<35 to 200 [33]
Mexican pinyonP. cembroides20-70 [91,132]
Rocky Mountain lodgepole pine*P. contorta var. latifolia25-300+ [7,8,112]
Sierra lodgepole pine*P. contorta var. murrayana35-200 [7]
shortleaf pineP. echinata2-15
shortleaf pine-oakP. echinata-Quercus spp.< 10 [144]
Colorado pinyonP. edulis10-400+ [44,50,75,97]
slash pineP. elliottii3-8
slash pine-hardwoodP. elliottii-variable< 35
sand pineP. elliottii var. elliottii25-45 [144]
Jeffrey pineP. jeffreyi5-30
western white pine*P. monticola50-200 [8]
longleaf-slash pineP. palustris-P. elliottii1-4 [94,144]
longleaf pine-scrub oakP. palustris-Quercus spp.6-10 [144]
Pacific ponderosa pine*P. ponderosa var. ponderosa1-47 [8]
interior ponderosa pine*P. ponderosa var. scopulorum2-30 [8,12,80]
Arizona pineP. ponderosa var. arizonica2-15 [12,28,119]
Table Mountain pineP. pungens< 35 to 200 [144]
red pine (Great Lakes region)P. resinosa10-200 (10**) [33,46]
red-white-jack pine*P. resinosa-P. strobus-P. banksiana10-300 [33,58]
pitch pineP. rigida6-25 [21,59]
pocosinP. serotina3-8
pond pineP. serotina3-8
eastern white pineP. strobus35-200
eastern white pine-eastern hemlockP. strobus-Tsuga canadensis35-200
eastern white pine-northern red oak-red mapleP. strobus-Quercus rubra-Acer rubrum35-200
loblolly pineP. taeda3-8
loblolly-shortleaf pineP. taeda-P. echinata10 to < 35
Virginia pineP. virginiana10 to < 35
Virginia pine-oakP. virginiana-Quercus spp.10 to < 35
sycamore-sweetgum-American elmPlatanus occidentalis-Liquidambar styraciflua-Ulmus americana< 35 to 200 [144]
galleta-threeawn shrubsteppePleuraphis jamesii-Aristida purpurea< 35 to < 100
eastern cottonwoodPopulus deltoides< 35 to 200 [97]
aspen-birchP. tremuloides-Betula papyrifera35-200 [33,144]
quaking aspen (west of the Great Plains)P. tremuloides7-120 [8,55,86]
mesquiteProsopis glandulosa< 35 to < 100 [85,97]
mesquite-buffalo grassP. glandulosa-Buchloe dactyloides< 35
Texas savannaP. glandulosa var. glandulosa< 10 [97]
black cherry-sugar maplePrunus serotina-Acer saccharum> 1000 [144]
mountain grasslandsPseudoroegneria spicata3-40 (10**) [7,8]
Rocky Mountain Douglas-fir*Pseudotsuga menziesii var. glauca25-100 [8,9,10]
coastal Douglas-fir*P. menziesii var. menziesii40-240 [8,92,109]
California mixed evergreenP. menziesii var. m.-Lithocarpus densiflorus-Arbutus menziesii< 35
California oakwoodsQuercus spp.< 35 [8]
oak-hickoryQuercus-Carya spp.< 35[144]
oak-juniper woodland (Southwest)Quercus-Juniperus spp.< 35 to < 200 [97]
northeastern oak-pineQuercus-Pinus spp.10 to < 35 [144]
oak-gum-cypressQuercus-Nyssa-spp.-Taxodium distichum35 to > 200 [94]
southeastern oak-pineQuercus-Pinus spp.< 10 [144]
coast live oakQ. agrifolia2-75 [52]
white oak-black oak-northern red oakQ. alba-Q. velutina-Q. rubra< 35 [144]
canyon live oakQ. chrysolepis<35 to 200
blue oak-foothills pineQ. douglasii-Pinus sabiniana<35 [8]
northern pin oakQ. ellipsoidalis< 35 [144]
Oregon white oakQ. garryana< 35 [8]
bear oakQ. ilicifolia< 35 >[144]
California black oakQ. kelloggii5-30 [97]
bur oakQ. macrocarpa< 10 [144]
oak savannaQ. macrocarpa/Andropogon gerardii-Schizachyrium scoparium2-14 [97,144]
shinneryQ. mohriana< 35 [97]
chestnut oakQ. prinus3-8
northern red oakQ. rubra10 to < 35
post oak-blackjack oakQ. stellata-Q. marilandica< 10
black oakQ. velutina< 35
live oakQ. virginiana10 to< 100 [144]
interior live oakQ. wislizenii< 35 [8]
cabbage palmetto-slash pineSabal palmetto-Pinus elliottii< 10 [94,144]
blackland prairieSchizachyrium scoparium-Nassella leucotricha< 10
Fayette prairieS. scoparium-Buchloe dactyloides< 10
little bluestem-grama prairieS. scoparium-Bouteloua spp.< 35
tule marshesScirpus and/or Typha spp.< 35 [144]
redwoodSequoia sempervirens5-200 [8,42,131]
southern cordgrass prairieSpartina alterniflora1-3 [97]
baldcypressTaxodium distichum var. distichum100 to > 300
pondcypressT. distichum var. nutans< 35 [94]
western redcedar-western hemlockThuja plicata-Tsuga heterophylla> 200 [8]
eastern hemlock-yellow birchT. canadensis-Betula alleghaniensis> 200 [144]
western hemlock-Sitka spruceT. heterophylla-Picea sitchensis> 200
mountain hemlock*T. mertensiana35 to > 200 [8]
elm-ash-cottonwoodUlmus-Fraxinus-Populus spp.< 35 to 200 [33,144]
*fire return interval varies widely; trends in variation are noted in the species summary
**mean

Fire Management Considerations

Fire as a Control Agent

There are no published studies on using fire to control herb sophia, but given herb sophia's strong response to increased light and nutrients and open ground, fire alone is unlikely to provide control. If herb sophia is already onsite in the seed bank, or as a few plants, fire is likely to increase the species' importance in the early postfire community.

Interactions with Cheatgrass

If present in the seed bank, herb sophia is liable to dominate early postfire communities if the seedbed or the postfire climate are unfavorable for cheatgrass establishment [37,38,100]. Even when cheatgrass dominates the postfire community, herb sophia is likely to be an important forb. The 2 species are frequently found together in the prefire seed bank. In a big sagebrush-rubber rabbitbrush (Chrysothamnus nauseosus) community in Wyoming, cheatgrass dominated the seed bank, but herb sophia was 1 of the most important forbs in the seed bank [93]. Succession after a July 1985 wildfire on the Snake River Birds of Prey Area, southwestern Idaho, followed a typical pattern, with herb sophia showing greater cover than any other plant species except cheatgrass. There was much open ground in the area, especially on sites prepared for postfire rehabilitation [54].

Mean percent cover of herb sophia, cheatgrass, and bare ground 1 year after a 1985 wildfire on the Snake River Birds of Prey Area, southwestern Idaho [54].
Plot conditionBurnedPartially burnedBurned and rehabilitated*Unburned, untreated control
Herb sophia536< 1
Cheatgrass269145
Bare ground22225422
*drill-seeded with crested wheatgrass (Agropyron cristatum), yellow sweetclover (Melilotus officinalis), and fourwing saltbush (Atriplex canescens)

Interactions with Western and Other Tansymustards

Although they are taxonomically and ecologically similar, little is known of possible growth interference of exotic herb sophia to western and other native tansymustards in postfire environments. Limited studies are inconclusive, and further research is needed in this area. A review by Wright and others [151] describes herb sophia as more resilient to fall prescribed burning than western tansymustard ("undamaged" vs. "slightly damaged" by fall fire, respectively). Postfire responses of the 2 species probably depend upon their relative abundance in the prefire seed bank and poorly understood differences in germination and seedling establishment requirements. Floyd-Hanna and others [45] noted the presence of both species after the Chapin 5 Wildfire at Mesa Verde National Park in the summer of 1996. Herb sophia was more frequent on study plots than western tansymustard at postfire year 1. Herb sophia was not observed on study plots at postfire year 2, while western tansymustard increased [45].

Herb sophia and western tansymustard frequencies (%) on burn sites in different plant communities 1 and 2 years after the 1996 Chapin 5 Wildfire at Mesa Verde National Park [45].
Plant communityHerb sophiaWestern tansymustard
1997199819971998
Gambel oak/Utah serviceberry* mountain shrubland160331
Gambel oak-Colorado pinyon-Utah juniper120124
Colorado pinyon-Utah juniper100227

Federal Status

None

Other Status

Herb sophia is classified as a noxious weed list in Colorado and Minnesota [137,138].

Importance to Wildlife and Livestock

Herb sophia is toxic to livestock, causing blindness, staggering, and loss of ability to swallow. All parts of the plant contain poisonous levels of nitrate [43,123]. The seeds contain poisonous isoallyl thiocyanates and irritant oils. Large quantities of the plant must be consumed for long periods of time for poisoning to occur [43].

Wildlife use of herb sophia and other tansymustards is poorly documented, and further studies are needed to determine the relative importance of tansymustards in animal communities.

Small mammals: Townsend's ground squirrels graze tansymustards, sometimes in large quantity. Spring use of tansymustard has ranged from 3% on the Snake River Birds of Prey Area in southwestern Idaho to 33% in eastern Washington [71,111,154].

Birds: Sage-grouse in Nevada grazed most of the early spring forbs in a big sagebrush community, but avoided herb sophia [117]. In free-choice trials, chukar preferred western tansymustard seeds to cheatgrass seeds, which form the main staple of their diet [155].

Herb sophia is a larval food for orangetip, white checkered, and white cabbage butterflies [68].

Palatability and Nutritional Value

Herb sophia is moderately palatable to livestock, although livestock may prefer other tansymustard species. In free-choice trials, cattle in Montana selected western tansymustard more often than herb sophia [99].

Cover Value

No information.

Other Uses

Herb sophia seeds have a flavor similar to commercial black mustard (Brassica nigra) seeds, and are used as a spice [32]. The Navajo used ground herb sophia seeds in baked goods [140]. The stems and leaves are used as fiber in India [139].

Photo of a field filled with a bunchy green plant with yellow flowers and some areas of bare ground.
Photo Credit
Photo by Joseph M. DiTomaso, University of California - Davis, Bugwood.org.

Field infested with herb sophia.

Impacts

The greatest impact of herb sophia and other tansymustards to wildlands is probably their role in facilitating succession. See Successional Status for further information.

Herb sophia invades rangelands disturbed by heavy grazing [105]. It is a common volunteer on restoration and rehabilitation projects [122,143].

Herb sophia is a crop pest [89] and an alternate host for beet leafhoppers, which transmit curly top virus to sugar beet (Beta vulgaris) crops [65].

Prevention

Since herb sophia is an early seral species, minimizing soil disturbance and seed dispersal and maintaining a healthy plant community is the best way to prevent establishment of herb sophia [25].

Control

Herb sophia does not usually persist in late-seral communities and may not require special control measures. Canopy closure, litter accumulation and/or growth interference from later-successional species tend to exclude tansymustard over time. For example, herb sophia volunteered between rough fescue sod patches on a restoration project in Alberta. As the rough fescue grew and litter accumulated, herb sophia became less abundant [108]. Perhaps because it is largely controlled by succession, there is scant wildland-management interest in using resource monies to control herb sophia with fire, herbicides, or other treatments.

Fire

See Fire Management Considerations.

Physical and Mechanical Control

Small infestations of herb sophia can be controlled by hand pulling rosettes in the fall or early spring [25].

Biological Control

There are no biological control organisms reported for herb sophia [25].

Chemical Control

Herbicides are effective in gaining initial control of a new invasion or a severe infestation, but are rarely a complete or long-term solution to weed management [24]. Herbicides are more effective on large infestations when incorporated into long-term management plans that include replacement of weeds with desirable species, careful land use management, and prevention of new infestations. Control with herbicides is temporary, as it does not change those conditions that allow infestations to occur [157]. See the Weed Control Methods Handbook for considerations on the use of herbicides in natural areas and detailed information on specific chemicals.

Herb sophia seedlings are sensitive to most herbicides at relatively low application rates. Glyphosate and 2,4-D give excellent control [135,148], as do many other herbicides [148]. Herbicide choice and rates are influenced by growth stage, stand density, and environmental conditions (e.g. drought or cold temperatures). Check with state or county weed specialists for appropriate local use rates and timing.

Integrated Management

Land management practices that promote later-successional species can exclude herb sophia from most plant communities [25]. Some communities, such as sagebrush steppe and salt-desert shrubland, maintain open light and bare ground conditions well into late succession [81]. For these communities, herb sophia is controlled by eliminating seed production until the seed bank is depleted. Mechanical treatment or herbicide application prior to seed set treats established plants [25]. Managers are encouraged to use combinations of control techniques that are appropriate to the site objectives, desired plant community, available resources, and timing of application. For information on integrated weed management without herbicides, see the Bio-Integral Resource Center (BIRC) website.

Revegetation

Copy text

The following biogeographic classification systems are presented as a guide to demonstrate where herb sophia may be found. Precise distribution information is limited. Because it is so widespread, it is difficult to exclude many ecosystems as potential hosts of herb sophia plants or populations; therefore, these lists are speculative.

Table A1— Forest and range ecosystems, Bureau of Land Management (BLM) physiographic regions, Kuchler plant associations, Society for American Foresters (SAF) forest cover types, and Society for Rangeland Management (SRM) rangeland cover types in which this species occurs.

Forest and Range Ecosystems (Garrison et al. 1977)

  • FRES10 White-red-jack pine
  • FRES11 Spruce-fir
  • FRES12 Longleaf-slash pine
  • FRES13 Loblolly-shortleaf pine
  • FRES14 Oak-pine
  • FRES15 Oak-hickory
  • FRES16 Oak-gum-cypress
  • FRES17 Elm-ash-cottonwood
  • FRES18 Maple-beech-birch
  • FRES19 Aspen-birch
  • FRES20 Douglas-fir
  • FRES21 Ponderosa pine
  • FRES22 Western white pine
  • FRES23 Fir-spruce
  • FRES24 Hemlock-Sitka spruce
  • FRES25 Larch
  • FRES26 Lodgepole pine
  • FRES27 Redwood
  • FRES28 Western hardwoods
  • FRES29 Sagebrush
  • FRES30 Desert shrub
  • FRES31 Shinnery
  • FRES32 Texas savanna
  • FRES33 Southwestern shrubsteppe
  • FRES34 Chaparral-mountain shrub
  • FRES35 Pinyon-juniper
  • FRES36 Mountain grasslands
  • FRES37 Mountain meadows
  • FRES38 Plains grasslands
  • FRES39 Prairie
  • FRES40 Desert grasslands
  • FRES41 Wet grasslands
  • FRES42 Annual grasslands
  • FRES44 Alpine

BLM Physiographic Regions (Bernard and Brown 1977)

  • 1 Northern Pacific Border
  • 2 Cascade Mountains
  • 3 Southern Pacific Border
  • 4 Sierra Mountains
  • 5 Columbia Plateau
  • 6 Upper Basin and Range
  • 7 Lower Basin and Range
  • 8 Northern Rocky Mountains
  • 9 Middle Rocky Mountains
  • 10 Wyoming Basin
  • 11 Southern Rocky Mountains
  • 12 Colorado Plateau
  • 13 Rocky Mountain Piedmont
  • 14 Great Plains
  • 15 Black Hills Uplift
  • 16 Upper Missouri Basin and Broken Lands

Kuchler Plant Associations (Kuchler 1964)

  • K001 Spruce-cedar-hemlock forest
  • K002 Cedar-hemlock-Douglas-fir forest
  • K003 Silver fir-Douglas-fir forest
  • K004 Fir-hemlock forest
  • K005 Mixed conifer forest
  • K006 Redwood forest
  • K007 Red fir forest
  • K008 Lodgepole pine-subalpine forest
  • K009 Pine-cypress forest
  • K010 Ponderosa shrub forest
  • K011 Western ponderosa forest
  • K012 Douglas-fir forest
  • K013 Cedar-hemlock-pine forest
  • K014 Grand fir-Douglas-fir forest
  • K015 Western spruce-fir forest
  • K016 Eastern ponderosa forest
  • K017 Black Hills pine forest
  • K018 Pine-Douglas-fir forest
  • K019 Arizona pine forest
  • K020 Spruce-fir-Douglas-fir forest
  • K021 Southwestern spruce-fir forest
  • K022 Great Basin pine forest
  • K023 Juniper-pinyon woodland
  • K024 Juniper steppe woodland
  • K025 Alder-ash forest
  • K026 Oregon oakwoods
  • K027 Mesquite bosques
  • K028 Mosaic of K002 and K026
  • K029 California mixed evergreen forest
  • K030 California oakwoods
  • K031 Oak-juniper woodland
  • K032 Transition between K031 and K037
  • K033 Chaparral
  • K034 Montane chaparral
  • K035 Coastal sagebrush
  • K036 Mosaic of K030 and K035
  • K037 Mountain-mahogany-oak scrub
  • K038 Great Basin sagebrush
  • K039 Blackbrush
  • K040 Saltbush-greasewood
  • K041 Creosote bush
  • K042 Creosote bush-bur sage
  • K043 Paloverde-cactus shrub
  • K044 Creosote bush-tarbush
  • K045 Ceniza shrub
  • K046 Desert: vegetation largely lacking
  • K047 Fescue-oatgrass
  • K048 California steppe
  • K049 Tule marshes
  • K050 Fescue-wheatgrass
  • K051 Wheatgrass-bluegrass
  • K052 Alpine meadows and barren
  • K053 Grama-galleta steppe
  • K054 Grama-tobosa prairie
  • K055 Sagebrush steppe
  • K056 Wheatgrass-needlegrass shrubsteppe
  • K057 Galleta-threeawn shrubsteppe
  • K058 Grama-tobosa shrubsteppe
  • K059 Trans-Pecos shrub savanna
  • K060 Mesquite savanna
  • K061 Mesquite-acacia savanna
  • K062 Mesquite-live oak savanna
  • K063 Foothills prairie
  • K064 Grama-needlegrass-wheatgrass
  • K065 Grama-buffalo grass
  • K066 Wheatgrass-needlegrass
  • K067 Wheatgrass-bluestem-needlegrass
  • K068 Wheatgrass-grama-buffalo grass
  • K069 Bluestem-grama prairie
  • K070 Sandsage-bluestem prairie
  • K071 Shinnery
  • K072 Sea oats prairie
  • K073 Northern cordgrass prairie
  • K074 Bluestem prairie
  • K075 Nebraska Sandhills prairie
  • K076 Blackland prairie
  • K077 Bluestem-sacahuista prairie
  • K078 Southern cordgrass prairie
  • K079 Palmetto prairie
  • K080 Marl everglades
  • K081 Oak savanna
  • K082 Mosaic of K074 and K100
  • K083 Cedar glades
  • K084 Cross Timbers
  • K085 Mesquite-buffalo grass
  • K086 Juniper-oak savanna
  • K087 Mesquite-oak savanna
  • K088 Fayette prairie
  • K089 Black Belt
  • K090 Live oak-sea oats
  • K091 Cypress savanna
  • K092 Everglades
  • K093 Great Lakes spruce-fir forest
  • K094 Conifer bog
  • K095 Great Lakes pine forest
  • K096 Northeastern spruce-fir forest
  • K097 Southeastern spruce-fir forest
  • K098 Northern floodplain forest
  • K099 Maple-basswood forest
  • K100 Oak-hickory forest
  • K101 Elm-ash forest
  • K102 Beech-maple forest
  • K103 Mixed mesophytic forest
  • K104 Appalachian oak forest
  • K105 Mangrove
  • K106 Northern hardwoods
  • K107 Northern hardwoods-fir forest
  • K108 Northern hardwoods-spruce forest
  • K109 Transition between K104 and K106
  • K110 Northeastern oak-pine forest
  • K111 Oak-hickory-pine
  • K112 Southern mixed forest
  • K113 Southern floodplain forest
  • K114 Pocosin
  • K115 Sand pine scrub
  • K116 Subtropical pine forest

SAF Cover Types (Eyre 1980)

  • 1 Jack pine
  • 5 Balsam fir
  • 12 Black spruce
  • 13 Black spruce-tamarack
  • 14 Northern pin oak
  • 15 Red pine
  • 16 Aspen
  • 17 Pin cherry
  • 18 Paper birch
  • 19 Gray birch-red maple
  • 20 White pine-northern red oak-red maple
  • 21 Eastern white pine
  • 22 White pine-hemlock
  • 23 Eastern hemlock
  • 24 Hemlock-yellow birch
  • 25 Sugar maple-beech-yellow birch
  • 26 Sugar maple-basswood
  • 27 Sugar maple
  • 28 Black cherry-maple
  • 30 Red spruce-yellow birch
  • 31 Red spruce-sugar maple-beech
  • 32 Red spruce
  • 33 Red spruce-balsam fir
  • 34 Red spruce-Fraser fir
  • 35 Paper birch-red spruce-balsam fir
  • 37 Northern white-cedar
  • 38 Tamarack
  • 39 Black ash-American elm-red maple
  • 40 Post oak-blackjack oak
  • 42 Bur oak
  • 43 Bear oak
  • 44 Chestnut oak
  • 45 Pitch pine
  • 46 Eastern redcedar
  • 50 Black locust
  • 51 White pine-chestnut oak
  • 52 White oak-black oak-northern red oak
  • 53 White oak
  • 55 Northern red oak
  • 57 Yellow-poplar
  • 58 Yellow-poplar-eastern hemlock
  • 59 Yellow-poplar-white oak-northern red oak
  • 60 Beech-sugar maple
  • 61 River birch-sycamore
  • 62 Silver maple-American elm
  • 63 Cottonwood
  • 64 Sassafras-persimmon
  • 65 Pin oak-sweetgum
  • 66 Ashe juniper-redberry (Pinchot) juniper
  • 67 Mohrs (shin) oak
  • 68 Mesquite
  • 69 Sand pine
  • 70 Longleaf pine
  • 71 Longleaf pine-scrub oak
  • 72 Southern scrub oak
  • 73 Southern redcedar
  • 74 Cabbage palmetto
  • 75 Shortleaf pine
  • 76 Shortleaf pine-oak
  • 78 Virginia pine-oak
  • 79 Virginia pine
  • 80 Loblolly pine-shortleaf pine
  • 81 Loblolly pine
  • 82 Loblolly pine-hardwood
  • 83 Longleaf pine-slash pine
  • 84 Slash pine
  • 85 Slash pine-hardwood
  • 87 Sweetgum-yellow-poplar
  • 88 Willow oak-water oak-diamondleaf (laurel) oak
  • 89 Live oak
  • 91 Swamp chestnut oak-cherrybark oak
  • 92 Sweetgum-willow oak
  • 93 Sugarberry-American elm-green ash
  • 94 Sycamore-sweetgum-American elm
  • 95 Black willow
  • 96 Overcup oak-water hickory
  • 97 Atlantic white-cedar
  • 98 Pond pine
  • 100 Pondcypress
  • 101 Baldcypress
  • 102 Baldcypress-tupelo
  • 103 Water tupelo-swamp tupelo
  • 104 Sweetbay-swamp tupelo-redbay
  • 105 Tropical hardwoods
  • 106 Mangrove
  • 107 White spruce
  • 108 Red maple
  • 109 Hawthorn
  • 110 Black oak
  • 111 South Florida slash pine
  • 201 White spruce
  • 202 White spruce-paper birch
  • 203 Balsam poplar
  • 204 Black spruce
  • 205 Mountain hemlock
  • 206 Engelmann spruce-subalpine fir
  • 207 Red fir
  • 208 Whitebark pine
  • 209 Bristlecone pine
  • 210 Interior Douglas-fir
  • 211 White fir
  • 212 Western larch
  • 213 Grand fir
  • 215 Western white pine
  • 216 Blue spruce
  • 217 Aspen
  • 218 Lodgepole pine
  • 219 Limber pine
  • 220 Rocky Mountain juniper
  • 221 Red alder
  • 222 Black cottonwood-willow
  • 223 Sitka spruce
  • 224 Western hemlock
  • 225 Western hemlock-Sitka spruce
  • 226 Coastal true fir-hemlock
  • 227 Western redcedar-western hemlock
  • 228 Western redcedar
  • 229 Pacific Douglas-fir
  • 230 Douglas-fir-western hemlock
  • 231 Port-Orford-cedar
  • 232 Redwood
  • 233 Oregon white oak
  • 234 Douglas-fir-tanoak-Pacific madrone
  • 235 Cottonwood-willow
  • 236 Bur oak
  • 237 Interior ponderosa pine
  • 238 Western juniper
  • 239 Pinyon-juniper
  • 240 Arizona cypress
  • 241 Western live oak
  • 242 Mesquite
  • 243 Sierra Nevada mixed conifer
  • 244 Pacific ponderosa pine-Douglas-fir
  • 245 Pacific ponderosa pine
  • 246 California black oak
  • 247 Jeffrey pine
  • 248 Knobcone pine
  • 249 Canyon live oak
  • 250 Blue oak-foothills pine
  • 251 White spruce-aspen
  • 252 Paper birch
  • 253 Black spruce-white spruce
  • 254 Black spruce-paper birch
  • 255 California coast live oak
  • 256 California mixed subalpine

SRM Rangeland Cover Types (Shiflet 1994)

  • 101 Bluebunch wheatgrass
  • 102 Idaho fescue
  • 103 Green fescue
  • 104 Antelope bitterbrush-bluebunch wheatgrass
  • 105 Antelope bitterbrush-Idaho fescue
  • 106 Bluegrass scabland
  • 107 Western juniper/big sagebrush/bluebunch wheatgrass
  • 108 Alpine Idaho fescue
  • 109 Ponderosa pine shrubland
  • 110 Ponderosa pine-grassland
  • 201 Blue oak woodland
  • 202 Coast live oak woodland
  • 203 Riparian woodland
  • 204 North coastal shrub
  • 205 Coastal sage shrub
  • 206 Chamise chaparral
  • 207 Scrub oak mixed chaparral
  • 208 Ceanothus mixed chaparral
  • 209 Montane shrubland
  • 210 Bitterbrush
  • 211 Creosote bush scrub
  • 212 Blackbush
  • 213 Alpine grassland
  • 214 Coastal prairie
  • 215 Valley grassland
  • 216 Montane meadows
  • 217 Wetlands
  • 301 Bluebunch wheatgrass-blue grama
  • 302 Bluebunch wheatgrass-Sandberg bluegrass
  • 303 Bluebunch wheatgrass-western wheatgrass
  • 304 Idaho fescue-bluebunch wheatgrass
  • 305 Idaho fescue-Richardson needlegrass
  • 306 Idaho fescue-slender wheatgrass
  • 307 Idaho fescue-threadleaf sedge
  • 308 Idaho fescue-tufted hairgrass
  • 309 Idaho fescue-western wheatgrass
  • 310 Needle-and-thread-blue grama
  • 311 Rough fescue-bluebunch wheatgrass
  • 312 Rough fescue-Idaho fescue
  • 313 Tufted hairgrass-sedge
  • 314 Big sagebrush-bluebunch wheatgrass
  • 315 Big sagebrush-Idaho fescue
  • 316 Big sagebrush-rough fescue
  • 317 Bitterbrush-bluebunch wheatgrass
  • 318 Bitterbrush-Idaho fescue
  • 319 Bitterbrush-rough fescue
  • 320 Black sagebrush-bluebunch wheatgrass
  • 321 Black sagebrush-Idaho fescue
  • 322 Curlleaf mountain-mahogany-bluebunch wheatgrass
  • 323 Shrubby cinquefoil-rough fescue
  • 324 Threetip sagebrush-Idaho fescue
  • 401 Basin big sagebrush
  • 402 Mountain big sagebrush
  • 403 Wyoming big sagebrush
  • 404 Threetip sagebrush
  • 405 Black sagebrush
  • 406 Low sagebrush
  • 407 Stiff sagebrush
  • 408 Other sagebrush types
  • 409 Tall forb
  • 410 Alpine rangeland
  • 411 Aspen woodland
  • 412 Juniper-pinyon woodland
  • 413 Gambel oak
  • 414 Salt desert shrub
  • 415 Curlleaf mountain-mahogany
  • 416 True mountain-mahogany
  • 417 Littleleaf mountain-mahogany
  • 418 Bigtooth maple
  • 419 Bittercherry
  • 420 Snowbrush
  • 421 Chokecherry-serviceberry-rose
  • 422 Riparian
  • 501 Saltbush-greasewood
  • 502 Grama-galleta
  • 503 Arizona chaparral
  • 504 Juniper-pinyon pine woodland
  • 505 Grama-tobosa shrub
  • 506 Creosotebush-bursage
  • 507 Palo verde-cactus
  • 508 Creosotebush-tarbush
  • 509 Transition between oak-juniper woodland and mahogany-oak association
  • 601 Bluestem prairie
  • 602 Bluestem-prairie sandreed
  • 603 Prairie sandreed-needlegrass
  • 604 Bluestem-grama prairie
  • 605 Sandsage prairie
  • 606 Wheatgrass-bluestem-needlegrass
  • 607 Wheatgrass-needlegrass
  • 608 Wheatgrass-grama-needlegrass
  • 609 Wheatgrass-grama
  • 610 Wheatgrass
  • 611 Blue grama-buffalo grass
  • 612 Sagebrush-grass
  • 613 Fescue grassland
  • 614 Crested wheatgrass
  • 615 Wheatgrass-saltgrass-grama
  • 701 Alkali sacaton-tobosagrass
  • 702 Black grama-alkali sacaton
  • 703 Black grama-sideoats grama
  • 704 Blue grama-western wheatgrass
  • 705 Blue grama-galleta
  • 706 Blue grama-sideoats grama
  • 707 Blue grama-sideoats grama-black grama
  • 708 Bluestem-dropseed
  • 709 Bluestem-grama
  • 710 Bluestem prairie
  • 711 Bluestem-sacahuista prairie
  • 712 Galleta-alkali sacaton
  • 713 Grama-muhly-threeawn
  • 714 Grama-bluestem
  • 715 Grama-buffalo grass
  • 716 Grama-feathergrass
  • 717 Little bluestem-Indiangrass-Texas wintergrass
  • 718 Mesquite-grama
  • 719 Mesquite-liveoak-seacoast bluestem
  • 720 Sand bluestem-little bluestem (dunes)
  • 721 Sand bluestem-little bluestem (plains)
  • 722 Sand sagebrush-mixed prairie
  • 723 Sea oats
  • 724 Sideoats grama-New Mexico feathergrass-winterfat
  • 725 Vine mesquite-alkali sacaton
  • 726 Cordgrass
  • 727 Mesquite-buffalo grass
  • 728 Mesquite-granjeno-acacia
  • 729 Mesquite
  • 730 Sand shinnery oak
  • 731 Cross timbers-Oklahoma
  • 732 Cross timbers-Texas (little bluestem-post oak)
  • 733 Juniper-oak
  • 734 Mesquite-oak
  • 735 Sideoats grama-sumac-juniper
  • 801 Savanna
  • 802 Missouri prairie
  • 803 Missouri glades
  • 804 Tall fescue
  • 805 Riparian
  • 806 Gulf Coast salt marsh
  • 807 Gulf Coast fresh marsh
  • 808 Sand pine scrub
  • 809 Mixed hardwood and pine
  • 810 Longleaf pine-turkey oak hills
  • 811 South Florida flatwoods
  • 812 North Florida flatwoods
  • 813 Cutthroat seeps
  • 814 Cabbage palm flatwoods
  • 815 Upland hardwood hammocks
  • 816 Cabbage palm hammocks
  • 817 Oak hammocks
  • 818 Florida salt marsh
  • 819 Freshwater marsh and ponds
  • 820 Everglades flatwoods
  • 821 Pitcher plant bogs
  • 822 Slough
  • ALASKA RANGELANDS
  • 901 Alder
  • 902 Alpine herb
  • 903 Beach wildrye-mixed forb
  • 904 Black spruce-lichen
  • 905 Bluejoint reedgrass
  • 906 Broadleaf forest
  • 908 Fescue
  • 910 Hairgrass
  • 912 Low scrub shrub birch-ericaceous
  • 915 Mixed herb-herbaceous
  • 917 Tall shrub swamp
  • 918 Tussock tundra
  • 920 White spruce-paper birch
  • 921 Willow

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