IntroductIon Poisonous plants represent one of the greatest haz-ards to livestock ranching on western rangelands. In addition to direct losses by death, there are those due to weight loss, poor reproductive performance, and poor health. Through scientific reports and practical experience, ranch managers have learned to recog-nize poisonous plants and keep livestock losses to a minimum. Some of the things that can be done to prevent problems with poisonous plants are

1. Know the poisonous plants. This is the first line of defense against toxic plants.

2. Practice good range management. To a limited degree, poisonous plants will always be present on rangelands, but the real danger is when the plants are eaten. Livestock poisoning is more of-ten the result of poor range condition and poor management than the presence of poisonous plants. Most poisonous plants are unpalatable and will be eaten only if other good quality for-age is not available.

3. Feed adequate mineral and vitamin A supple-ments. Livestock in poor health are more suscep-tible to many toxins than are healthy animals.

4. Provide adequate forage, especially during early spring or drought periods.

5. Avoid driving livestock through infested or poor condition range. Hungry animals lose their se-lectivity, and poor rangelands contain far more poisonous plants than those in good condition.

6. Use control measures—herbicides, grubbing, etc. —on heavy infestations of toxic plants.

The most common toxins in New Mexico poi-sonous plants are alkaloids, glycosides, minerals, nitrogenous compounds, oxalates and other organic acids, compounds causing photosensitivity, and res-ins or resinoids (see Tables 1 and 2).

Alkaloids. These are the most powerful poisons and produce strong physiological reactions, general-ly affecting the nervous system. The alkaloid is usu-ally distributed throughout the plant and is active whether it is fresh or dry. There are no antidotes for alkaloid poisoning. Some of the common alkaloid-containing range plants are locoweeds (Astragalus spp.), larkspur (Delphinium spp.), groundsel (Sene-cio spp.), and lupine (Lupinus spp.).

Glycosides. Glycosides are compounds com-posed of a toxic agent combined with a sugar. The toxic agent is harmful when released from the gly-cosides. Cyanide (HCN, prussic acid) is the most common toxin in the glycosides. Glycoside levels in the plant are often related to environmental factors such as freezing, wilting, drought, and crushing. Cyanide is generally not retained in plant tissues after drying. Catclaw (Acacia greggii), chokecherry (Prunus virginiana), and johnsongrass (Sorghum halepense) are potential cyanide producers.

Minerals. Excessive absorption of certain miner-als may be dangerous to livestock. Selenium is pos-sibly the most important poisonous mineral in New Mexico. It may be found in some species of loco-

1Professor, Department of Animal and Range Sciences, New Mexico State University, Las Cruces.

To find more resources for your business, home, or family, visit the College of Agricultural, Consumer and Environmental Sciences on the World Wide Web at aces.nmsu.edu

An Annotated checklist of Poisonous or Injurious range Plants of new Mexico Circular 636Kelly W. Allred1

Cooperative Extension Service • College of Agricultural, Consumer and Environmental Sciences

This publication is scheduled to be updated and reissued 02/15.

Circular 636 • Page 2

weed (Astragalus spp.), fourwing saltbush (Atriplex canescens), snakeweed (Gutierrezia sarothrae), and asters (Aster spp.). Prince’s plume (Stanleya pinnata) grows only on seleniferous soils.

Nitrogenous compounds. Both range and crop plants may contain potentially toxic levels of ni-trogenous compounds. Care must be taken during drought or after fertilizer or herbicide application. Nitrates are also toxic in dry material and silage. Nitrogenous compounds are often found in many species of the amaranth (Amaranthaceae), sunflow-er (Asteraceae), mustard (Brassicaceae), and goose-foot (Chenopodiaceae) families.

Oxalates and organic acids. Many plants contain oxalates, but few species in New Mexico contain enough to be considered dangerous. Ha-logeton (Halogeton glomeratus) and dock (Rumex spp.) possess soluble oxalates that are corrosive to animal tissue. Non-ruminants are more susceptible to oxalate poisoning than ruminants because the large rumen capacity enables the animal to detoxify small amounts of soluble oxalates. Most cases of ru-minant poisoning occur on poor condition range-lands.

Compounds causing photosensitivity. On cer-tain occasions, animals become hypersensitive to light. Photodynamic pigments contained in horse-brush (Tetradymia spp.), lechuguilla (Agave lechu-guilla), sacahuista (Nolina spp.), and puncture-vine (Tribulus terrestris) react with light to produce swell-ing about the head, blistering, and a sunburned appearance. Damage may be so severe that the lips, ears, and eyelids may be lost. Bacterial infection may also set in.

Resins or resinoids. These are highly complex organic compounds that are present in a number of plants. Resins are found in milkweeds (Asclepias spp.), marijuana (Cannabis sativa), water hemlock (Cicuta maculata), and chinaberry tree (Melia aze-darach).

Several noxious plants contain no poisonous compounds, and instead cause injury through me-

chanical means if grazed. This is often by long awns or bristles (Aristida spp., Hordeum jubatum, Stipa spp.) or by stinging hairs (Urtiea spp.). PoIsonous PlAnts of neW MexIcoThere are at least 270 poisonous plants known to occur in New Mexico (Table 3). The following list includes all New Mexico range plants known to be poisonous or injurious to livestock or humans, even though many of these do not pose a threat except in exceptional circumstances. Also included are a few very common poisonous ornamentals or gar-den plants that may occasionally escape. The major poisonous plants that are likely to cause problems and should be watched for are marked with an as-terisk (*). The list is arranged in alphabetical order by plant family and scientific name. Indications of toxins and animals affected are only those reported and verified. The plants may be toxic to animals other than those listed.

Table 1. Plant Toxins and Their Effects on LivestockToxin Effect and Symptoms

Alkaloids Nervous system, liver damage, locoism, trembling, abortion, depression, paralysis, vomiting, loss of coordination, coma, and death

Glycosides Excitement, gasping, staggering, paralysis, prostration, convulsions, emphysema, blindness, coma, and death

Mineral Birth defects, loss of appetite, depression, labored poisoning breathing, excessive urination, coma, and death through respiratory and myocardial failure

Nitrogenous Abortion, depression of lactation, discolored compounds urine, vitamin A deficiency, brown blood, trembling, weakness, labored breathing, hemorrhages, coma, and death

Oxalates Nervous system, reduced coagulability of blood, acute kidney inflammation, dullness, colic, depression, labored breathing, prostration, weakness, coma, and death

Compounds causing Liver damage, inflammation of skin, itching, photosensitivity necrosis of skin, restlessness, leakage of serum through skin; death does not occur directly from the photodynamic action, but through kidney failure

Resins or resinoids Direct irritation of the nervous and muscular tissue, depression, weakness, staggering, labored breathing, elevated temperature, dilation of pupils, degeneration of kidneys, coma, and death

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Table 2. Distribution of Toxins in the Major Plant Families in New Mexico Number of species Number of species Number of speciesFamily in which toxin occurs Family in which toxin occurs Family in which toxin occurs Toxin in New Mexico Toxin in New Mexico Toxin in New MexicoFabaceae Photosensitization 2 Brassicaceae Alkaloids 21 Unknown 2 Allylisothiocyanate 2 Dicoumarin 2 Solanaceae Glycosides 1 Glycosides 3 Alkaloids 11 Mustard oil 1 Photosensitization 3 Glycosides 1 Selenium 1 Saponin 1 Unknown 2 Unknown 2 Selenium 13 Chenopodiaceae Ascelepiadaceae Unknown 10 Antihelminthic oil 1 Alkaloids 7Asteraceae Glycosides 1 Glycosides 7 Acrid substance 2 Nitrogenous compounds 3 Resinoids 7 Alcohol 1 Oxalates 4 Rosaceae Alkaloids 5 Photosensitization 1 Glycosides 7 Glycosides 3 Selenium 3 Euphorbiaceae Nitrogenous compounds 2 Ranunculaceae Acrid substance 3 Photosensitization 2 Alkaloids 6 Croton oil 1 Saponin 2 Glycosides 4 Photosensitization 1 Selenium 11 Hairballs 1 Unknown 1 Unknown 21 Irritant oils 1 Liliaceae Volatile oils 2 Apiaceae Alkaloids 4Poaceae Alcohol 2 Unknown 2 Fungus 1 Alkaloids 2 Polygonaceae Glycosides 3 Nitrogenous compounds 2 Nitrogenous compounds 1 Mechanically injurous 10 Unknown 2 Oxalates 4 Nitrogenous compounds 3 Photosensitization 1

Table 3. Number of Poisonous or Noxious Range Plants in New MexicoFamily Number of species Family Number of species Family Number of species

Fabaceae 52 Ranunculaceae 12 Rosaceae 6Asteraceae 50 Apiaceae 10 Polygonaceae 5Poaceae 32 Brassicaceae 8 38 other families 66Solanaceae 14 Asclepiadaceae 7Chenopodiaceae 12 Euphorbiaceae 7 Total 281

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AgavaceaeAgave lechuguilla Torr.Common name: lechuguillaToxin: unknown substances producing hepatogenic photosensitization; saponins Habitat: dry hills and plainsAnimals affected: sheep, goats

Nolina microcarpa Wats. Common name: beargrass, sacahuistaToxin: unknownHabitat: dry, rocky hills and plainsAnimals affected: cattle, sheep, goats

Nolina texana Wats. Common name: beargrass, sacahuistaToxin: unknownHabitat: dry, rocky hills and plainsAnimals affected: cattle, sheep, goats

Amaranthaceae*Amaranthus palmeri S. Wats. Common name: pigweed, carelessweed, redroot amaranthToxin: nitratesHabitat: gardens and old fields, waste areasAnimals affected: cattle, sheep, horses

*Amaranthus retroflexus L. Common name: pigweed, carelessweed, redroot amaranthToxin: nitratesHabitat: gardens and old fields, waste placesAnimals affected: cattle, sheep, horses

Anacardiaceae*Toxicodendron radicans (L.) KuntzeCommon name: poison ivyToxin: urushiol, a skin irritantHabitat: moist areas at lower elevations, ravinesAnimals affected: humans (dermatitis)

ApiaceaeApium graveolens L.Common name: celeryToxin: nitrates (in the tops)Habitat: waste groundAnimals affected: cattle

Berula erecta (Huds.) Cov. Common name: water parsnipToxin: alkaloidsHabitat: waterways, wet habitatsAnimals affected: cattle

*Cicuta maculata L.Common name: water hemlockToxin: cicutoxin (alcohol)Habitat: streams and marshesAnimals affected: all animals and humans

Conium maculatum L.Common name: poison hemlockToxin: alkaloids Habitat: moist roadsides, ditches, edges of culti-vated fieldsAnimals affected: all animals and humans

Daucus carota L. Common name: wild carrot, Queen Ann’s laceToxin: nitratesHabitat: waste areasAnimals affected: horses, cattle

Pastinaca sativa L. Common name: parsnipToxin: unknownHabitat: disturbed ground, cultivated areasAnimals affected: humans

Sium suave Walt. Common name: water parsnipToxin: unknownHabitat: marshes and wet soilsAnimals affected: cattle, swine

ApocynaceaeApocynum androsaemifolium L.Common name: spreading dogbaneToxin: resins, glycosidesHabitat: open places, coarse soils along streams, meadows, and wooded hillsidesAnimals affected: cats, dogs

Apocynum cannabinum L.Common name: dogbane, hemp dogbaneToxin: resins, glycosides

* Major poisonous plant

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Apocynaceae (contd.)Habitat: open places, coarse soils along streamsAnimals affected: cats, dogs

Nerium oleander L.Common name: oleanderToxin: glycosidesHabitat: common ornamentalAnimals affected: cattle, sheep, horses, humans

Asclepiadaceae*Asclepias asperula (Decne) WoodsonCommon name: rough milkweed, spider antelopehornToxin: resinoids, glycosides, alkaloidsHabitat: open dry plains, flats, desert swales, sandy or rocky hillsides with pinyon, juniper, or oakAnimals affected: sheep, cattle goats, horses, poultry

*Asclepias incarnata L.Common name: swamp milkweedToxin: resinoids, glycosides, alkaloidsHabitat: marshesAnimals affected: sheep, cattle, horses, poultry

*Asclepias latifolia (Torr.) Raf. Common name: broadleaf milkweedToxin: resinoids, glycosides, alkaloidsHabitat: dry plains in sandy soilsAnimals affected: sheep, goats

*Asclepias pumila Voil.Common name: low whorled milkweed, plains whorled milkweedToxin: resinoids, glycosides, alkaloidsHabitat: plains, low hillsAnimals affected: sheep, goats

*Asclepias speciosa Torr.Common name: showy milkweedToxin: resinoids, glycosides, alkaloidsHabitat: prairies, open areasAnimals affected: sheep, goats

*Asclepias subverticillata Vail. Common name: whorled milkweed, western whorled milkweedToxin: resinoides, glycosides, alkaloids

Habitat: dry plains and foothills, waterways, irriga-tion canalsAnimals affected: sheep, goats

*Asclepias verticillata L.Common name: whorled milkweedToxin: resinoids, glycosides, alkaloidsHabitat: plains of northeastern New MexicoAnimals affected: sheep, cattle, horses

AsteraceaeAchillea millefolium L. Common name: yarrowToxin: alkaloids and glycosidesHabitat: variousAnimals affected: cattle, sheep, horses

Anthemis cotula L.Common name: dog fennel, mayweedToxin: acrid substance irritating to mucous membranesHabitat: disturbed soils, fields, waste placesAnimals affected: poultry

Artemisia filifolia Torr. Common name: sand sagebrushToxin: volatile oilsHabitat: sandy soilsAnimals affected: horses

Artemisia spinescens (DC.) EatonCommon name: bud sagebrushToxin: volatile oilsHabitat: dry plains, hillsAnimals affected: cattle, sheep

Aster adscendens Lindl.Common name: asterToxin: seleniumHabitat: mountain meadowsAnimals affected: cattle, sheep

Aster coerulescens DC.Common name: asterToxin: seleniumHabitat: wet ground, along streamsAnimals affected: cattle, sheep

* Major poisonous plant

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Asteraceae (contd.)Aster commutatus GrayCommon name: asterToxin: seleniumHabitat: open fields, waste groundsAnimals affected: cattle, sheep

Aster ericoides L.Common name: asterToxin: seleniumHabitat: meadows, open woodsAnimals affected: cattle, sheep

Aster glaucoides BlakeCommon name: gray asterToxin: seleniumHabitat: mountainsAnimals affected: sheep

Aster laevis L.Common name: smooth asterToxin: seleniumHabitat: scattered in dry to moist placesAnimals affected: cattle, sheep

Aster occidentalis (Nutt.) Torr. & GrayCommon name: western asterToxin: seleniumHabitat: mountain meadows at moderate elevations Animals affected: cattle, sheep

Aster pauciflorus Nutt.Common name: fewheaded asterToxin: seleniumHabitat: widespread in saline soilsAnimals affected: cattle, sheep

Baccharis pteronioides DC.Common name: yerba-de-pasmoToxin: unknownHabitat: dry, open hillsAnimals affected: cattle, sheep

Bahia oppositifolia (Nutt.) DC.Common name: bahia, plains bahiaToxin: cyanogenetic glycosideHabitat: dry soils of plains and hillsAnimals affected: cattle, sheep

*Baileya multiradiata Harv. & GrayCommon name: desert baileya, desert marigoldToxin: unknownHabitat: sandy and gravelly soils in dry areasAnimals affected: sheep, goats

Centaurea repens L.Common name: Russian knapweedToxin: unknownHabitat: fields, roadsides, waste placesAnimals affected: horses

Centaurea solstitialis L.Common name: yellow starthistleToxin: unknownHabitat: waste groundsAnimals affected: horses

Chrysothamnus nauseosus (Pall.) BrittonCommon name: rubber rabbitbrushToxin: unknownHabitat: dry, open places at moderate and low elevationsAnimals affected: cattle, sheep, horses

Conyza coulteri GrayCommon name: conyzaToxin: unknownHabitat: plains, valleys, alkaline soilsAnimals affected: sheep

Flourensia cernua DC.Common name: tarbushToxin: unknownHabitat: dry plains, hills, mesasAnimals affected: sheep, goats

Grindelia squarrosa (Pursh) DunalCommon name: curlycup gumweedToxin: seleniumHabitat: dry open places, prairies, plains, roadsides, fieldsAnimals affected: cattle, sheep, horses

*Gutierrezia microcephala (DC.) GrayCommon name: broomweed, perennial snakeweed, turpentine weed, snakeweed, matchweedToxin: saponin

* Major poisonous plant

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Asteraceae (contd.)Habitat: dry plains, slopes, mesasAnimals affected: cattle, sheep, goats, swine, chicks, rabbits

*Gutierrezia sarothrae (Pursh) Britt. & Rusby Common name: broom snakeweed, snakeweed, matchbrush, turpentine weedToxin: saponinHabitat: dry stony plains, slopes, mesasAnimals affected: cattle, sheep, goats, swine, chicks, rabbits

*Haplopappus tenuisectus (Greene) BlakeCommon name: burrowweedToxin: tremetol (alcohol)Habitat: dry slopes and mesasAnimals affected: cattle, sheep

*Helenium autumnale L.Common name: sneezeweed, bitterweedToxin: unknown acrid substanceHabitat: moist low ground in lowlands and foothillsAnimals affected: cattle, sheep

*Helenium hoopesii GrayCommon name: sneezeweed, orange sneezeweedToxin: glycoside (dugaldin)Habitat: high mountain slopes and valleys, often forming dense stands in moist, sunny, undisturbed localitiesAnimals affected: cattle, sheep

*Helenium microcephalum DC.Common name: sneezeweedToxin: unknownHabitat: moist groundAnimals affected: cattle, sheep, horses, mules

*Hymenoxys odorata DC. Common name: bitterweed, bitter rubberweedToxin: unknownHabitat: semiarid rangeAnimals affected: sheep

*Hymenoxys richardsonii (Hook.) CockerellCommon name: pingue, Colorado rubberweed, rubberweed

Toxin: unknown, may be associated with mineral imbalanceHabitat: dry, rocky, or clay soils of plains and mountain slopesAnimals affected: cattle, sheep, goats

*Isocoma wrightii (Gray) Rydb.Common name: rayless goldenrod, jimmyweed, burrowweedToxin: tremetol (alcohol)Habitat: river valleys, drainage areas, irrigation canalsAnimals affected: cattle, sheep, horses

Lactuca serriola L.Common name: wild lettuceToxin: unknownHabitat: waste grounds, valleys, stream banksAnimals affected: cattle

*Oxytenia acerosa Nutt.Common name: copperweedToxin: unknownHabitat: alkaline soils in draws and streambeds, desert rangesAnimals affected: cattle, sheep

Psathyrotes annua (Nutt.) GrayCommon name: annual psathyrotesToxin: unknownHabitat: dry, sandy, often alkaline soils, especially creekbeds, dry washesAnimals affected: sheep

*Psilostrophe sparsiflora (Gray) A. Nels.Common name: paperflowerToxin: unknown, induces kidney damageHabitat: dry, open rangeAnimals affected: sheep

*Psilostrophe tagetinae (Nutt.) GreeneCommon name: paperflowerToxin: unknown, induces kidney damageHabitat: dry, open rangeAnimals affected: sheep

Rudbeckia laciniata L.Common name: golden glow, coneflower, thimble weed

* Major poisonous plant

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Asteraceae (contd.)Toxin: unknownHabitat: moist, rich soilsAnimals affected: swine, sheep

Rudbeckia hirta L.Common name: black-eyed SusanToxin: unknownHabitat: open slopes, meadowsAnimals affected: cattle, swine

Sartwellia flaveriae GrayCommon name: sartwelliaToxin: unknownHabitat: alkaline soils, gypsumAnimals affected: cattle, sheep, goats

*Senecio flaccidus LessingCommon name: threadleaf groundselToxin: pyrrolizidine alkaloidsHabitat: dry slopes, mesas, dry washesAnimals affected: cattle, sheep, horses, goats

*Senecio riddellii Torr. & GrayCommon name: Riddell’s groundselToxin: pyrrolizidine alkaloidsHabitat: dry, sandy soilsAnimals affected: cattle, sheep, horses, goats

Senecio spartioides Torr. & GrayCommon name: broom groundselToxin: pyrrolizidine alkaloidsHabitat: valleys, plains, open areas, pine forestsAnimals affected: cattle, sheep, horses, goats

Senecio vulgaris L.Common name: common groundselToxin: pyrrolizidine alkaloidsHabitat: gardens, disturbed groundAnimals affected: cattle, sheep, horses, goats

Sideranthus grindelioides (Nutt.) Rydb.Common name: ironweedToxin: seleniumHabitat: dry plains, rocky hillsAnimals affected: sheep

Tanacetum vulgare L.Common name: common tansy

Toxin: ethereal oil; causes abortionsHabitat: roadsides, waste areas, ditchbanks, moist areasAnimals affected: cattle

*Tetradymia canescens DC.Common name: horsebrushToxin: photosensitizing compoundsHabitat: dry desert and sagebrush rangeAnimals affected: sheep

*Tetradymia spinosa Torr. & GrayCommon name: spiny horsebrushToxin: photosensitzing compoundsHabitat: dry desert and sagebrush rangeAnimals affected: sheep

Viguiera annua (Jones) BlakeCommon name: annual goldeneyeToxin: unknownHabitat: dry hills and mesasAnimals affected: cattle

*Xanthium spinosum L.Common name: spiny cockleburToxin: hydroquinoneHabitat: waste places, fieldsAnimals affected: cattle, sheep, fowl, swine

*Xanthium strumarium L.Common name: cockleburToxin: hydroquinoneHabitat: fields and waste placesAnimals affected: cattle, sheep, horses, fowl, swine

BoraginaceaeAmsinckia intermedia Fisch & MayCommon name: fiddleneckToxin: unknownHabitat: dry, open, cultivated ground and waste areasAnimals affected: cattle, horses, swine

Cynoglossum officinale L. Common name: hounds tongueToxin: unknownHabitat: waste places in plains and hillsAnimals affected: cattle

* Major poisonous plant

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BrassicaceaeBarbarea vulgaris R. Br.Common name: yellow rocketToxin: mustard oilHabitat: wet meadows, waste placesAnimals affected: horses

Brassica hirta MoenchCommon name: white mustardToxin: cyanogenetic glycosideHabitat: cultivated fields, waste areasAnimals affected: cattle, sheep

Brassica kaber WheelerCommon name: charlockToxin: cyanogenetic glycosideHabitat: grain fields, waste areasAnimals affected: cattle, sheep, swine

Brassica nigra KochCommon name: black mustardToxin: goiterogenic glycosideHabitat: cultivated fieldsAnimals affected: cattle

*Descurainia pinnata (Walt.) Britt.Common name: tansy mustardToxin: unknownHabitat: sandy soilsAnimals affected: cattle

Raphanus raphanastrum L.Common name: wild radishToxin: unknownHabitat: cultivated areas, waste placesAnimals affected: cattle

Stanleya pinnata (Pursh) Britt.Common name: prince’s plumeToxin: seleniumHabitat: desert areas, dry plains and mesasAnimals affected: cattle, sheep

Thlaspi arvense L.Common name: field pennycressToxin: cyanogenetic glycosideHabitat: cultivated fields, waste areasAnimals affected: cattle

campanulaceaeLobelia cardinalis L.Common name: western cardinal flowerToxin: alkaloidsHabitat: wet groundAnimals affected: cattle, sheep, goats

cannabinaceaeCannabis sativa L.Common name: marijuanaToxin: tetrahydrocannabinolHabitat: waste placesAnimals affected: cattle, sheep, horses, humans

capparidaceaeWislizenia refracta Engelm.Common name: jackass cloverToxin: unknownHabitat: roadsides, fieldsAnimals affected: cattle

caprifoliaceaeSambucus mexicana Presl.Common name: Mexican elderToxin: unknownHabitat: valleys, stream banks, ornamentalAnimals affected: cattle, swine

Sambucus microbotrys Rydb.Common name: Rocky Mountain red elderToxin: unknown, concentrated in rootHabitat: moist woods, 8,000–12,000 feetAnimals affected: cattle, swine

caryophyllaceaeAgrostemma githago L.Common name: corn cockleToxin: cardiac glycosideHabitat: cultivated fields, waste placesAnimals affected: cattle, swine, poultry

*Drymaria pachyphylla Woot. & Standl.Common name: inkweed, drymaryToxin: unknownHabitat: alkaline clay soilsAnimals affected: cattle, sheep

* Major poisonous plant

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caryophyllaceae (contd.)Saponaria officinalis L.Common name: bouncing bet, soapwortToxin: saponinHabitat: waste areas, roadsidesAnimals affected: sheep, rabbits

Saponaria vaccaria L.Common name: cow cockleToxin: saponinHabitat: waste areas, roadsidesAnimals affected: sheep, rabbits

chenopodiaceaeAtriplex canescens (Pursh) JamesCommon name: four-wing saltbushToxin: seleniumHabitat: dry plains, canyonsAnimals affected: cattle, sheep

Atriplex nuttallii Wats. subsp. cuneata (A. Nels.)Common name: Nuttall saltbushToxin: seleniumHabitat: dry hills and slopesAnimals affected: cattle, sheep

Atriplex rosea L.Common name: red orache, red shadscaleToxin: seleniumHabitat: waste areasAnimals affected: cattle, sheep

Bassia hyssopifolia (Pall.) KuntzeCommon name: bassiaToxin: oxalatesHabitat: dry, saline areasAnimals affected: sheep

*Chenopodium album L.Common name: lambsquarter, goosefootToxin: nitratesHabitat: waste placesAnimals affected: cattle, sheep, horses

Chenopodium ambrosioides L.Common name: goosefootToxin: antihelminthic oil

Habitat: waste placesAnimals affected: geese

Chenopodium glaucum L.Common name: oakleaf goosefootToxin: nitratesHabitat: waste placesAnimals affected: cattle, sheep

*Halogeton glomeratus (Bieg.) C.A. Mey. Common name: halogeton, barillaToxin: oxalatesHabitat: dry saline plains and alkaline areas, roadsidesAnimals affected: cattle, sheep

Kochia scoparia (L.) Schrad.Common name: summer cypress, kochiaToxin: photosensitizing compoundsHabitat: dry soils, roadsides, waste placesAnimals affected: cattle, sheep, horses

Salsola tragus L.Common name: Russian thistle, tumbleweedToxin: nitratesHabitat: dry soils of plains and foothillsAnimals affected: cattle, sheep, horses

*Sarcobatus vermiculatus (Hook.) Torr.Common name: greasewoodToxin: oxalatesHabitat: alkaline flats or saline areas at low elevationsAnimals affected: sheep, sometimes cattle

Suckleya suckleyana (Torr.) Rydb.Common name: poison suckleyaToxin: hydrocyanic acidHabitat: moist ground, near ponds and reservoirsAnimals affected: cattle, sheep

cyperaceaeScirpus americanus Pers.Common name: bulrushToxin: unknown, suspected of producing pulmo-nary emphysemaHabitat: wet or moist groundAnimals affected: sheep, sometimes cattle

* Major poisonous plant

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equisetaceae*Equisetum arvense L.Common name: horsetail, scouring rushToxin: alkaloidsHabitat: sandy or gravelly soils along streams, moist fields, meadowsAnimals affected: cattle, sheep, horses, goats

*Equisetum hiemale L.Common name: scouring rush, horsetailToxin: alkaloidsHabitat: low moist areas, mostly along streamsAnimals affected: cattle, sheep, horses, goats

*Equisetum laevigatum R. Br.Common name: smooth horsetailToxin: thiaminaseHabitat: marshes, alluvial thickets, cultivated areasAnimals affected: cattle, sheep, horses, goats

euphorbiaceaeCroton texensis (Klotz.) DC.Common name: Texas crotonToxin: croton oil (caustic)Habitat: roadsides, fields, dry streambedsAnimals affected: cattle, sheep, horses

Euphorbia albomarginata Torr. & GrayCommon name: spurgeToxin: unknown photosensitizing substanceHabitat: dry flats and slopesAnimals affected: cattle, sheep

Euphorbia esula L.Common name: leafy spurgeToxin: unknown acrid principleHabitat: waste areasAnimals affected: sheep, horses

Euphorbia maculata L.Common name: eyebane, spotted spurgeToxin: unknown photosensitizing substanceHabitat: fields, slopes, canyonsAnimals affected: sheep

Euphorbia marginata PurshCommon name: snow-on-the-mountainToxin: unknown acrid principle

Habitat: plains, ornamentalAnimals affected: cattle, humans

Euphorbia prostrata Alt.Common name: euphorbiaToxin: unknown acrid principleHabitat: open plains and waste areasAnimals affected: cattle

Reverchonia arenaria GrayCommon name: reverchoniaToxin: unknownHabitat: dry, sandy groundAnimals affected: sheep

fabaceae*Acacia constricta Benth.Common name: whitethorn acaciaToxin: cyanogenetic glycosideHabitat: dry slopes and mesasAnimals affected: cattle

Acacia greggii GrayCommon name: catclaw acaciaToxin: cyanogenetic glycosideHabitat: along streams and washes; southern New MexicoAnimals affected: sheep

Astragalus albulus Woot. & Standl.Common name: Cibola milkvetchToxin: seleniumHabitat: clay flats, low hills, sandstone soilsAnimals affected: cattle, sheep, horses

Astragalus allochrous Gray var. allochrousCommon name: halfmoon locoweedToxin: swainsonineHabitat: dry slopes, plains, and valleysAnimals affected: cattle, sheep, horses

*Astragalus allochrous Gray var. playanus (M.E. Jones) IselyCommon name: Wooton locoweedToxin: alkaloid (locoine)Habitat: plains, slopes, valleysAnimals affected: cattle, sheep, horses

* Major poisonous plant

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fabaceae (contd.)*Astragalus bisulcatus (Hook.) Gray var. bisulcatusCommon name: two-grooved milkvetchToxin: seleniumHabitat: plains and bottomlands, sagebrush zonesAnimals affected: cattle, sheep, horses

*Astragalus bisulcatus var. haydenianus (Gray) BarnebyCommon name: two-grooved milkvetchToxin: seleniumHabitat: plains, dry slopes, sagebrush zoneAnimals affected: cattle, sheep, horses

Astragalus canadensis L.Common name: Canada milkvetchToxin: swainsonineHabitat: moist ground or sometimes rocky slopesAnimals affected: cattle, sheep, horses

Astragalus confertiflorus GrayCommon name: yellow milkvetchToxin: seleniumHabitat: rocky slopesAnimals affected: cattle, sheep, horses

Astragalus drummondii Hook.Common name: Drummond milkvetchToxin: swainsonineHabitat: plains and hillsides, brush placesAnimals affected: cattle, sheep, horses

Astragalus emoryanus (Rydb.) CoryCommon name: Emory milkvetchToxin: alkaloid, produces locoism when found on limestone soils or red sandy soilsHabitat: rocky hillsides, canyons, disturbed areasAnimals affected: cattle, sheep, goats

Astragalus flavus Torr. & GrayCommon name: yellow milkvetchToxin: seleniumHabitat: rocky slopes, low hillsAnimals affected: cattle, sheep, horses

*Astragalus lentiginosus Hook var. lentiginosusCommon name: blue locoToxin: swainsonineHabitat: rocky slopes, canyons, mesasAnimals affected: cattle, sheep, horses

*Astragalus lentiginosus Hook. var. diphysus (Gray) M.E. JonesCommon name: blue loco, rattleweedToxin: swainsonineHabitat: rocky slopes, canyons, mesasAnimals affected: cattle, sheep, horses

*Astragalus mollissimus Torr. var. mollissimusCommon name: woolly locoweedToxin: swainsonineHabitat: open plains and valleysAnimals affected: cattle, sheep, horses

*Astragalus mollissimus var. earlei (Rydb.) TidestromCommon name: woolly locoweedToxin: swainsonineHabitat: dry slopes and plainsAnimals affected: cattle, sheep, horses

*Astragalus nothoxys GrayCommon name: beaked milkvetchToxin: swainsonineHabitat: open slopes, sandy areas, among oak and juniperAnimals affected: cattle, sheep, horses

Astragalus oocalycis M.E. JonesCommon name: locoweedToxin: seleniumHabitat: dry hills, plains, valleysAnimals affected: cattle, sheep, horses

Astragalus pattersonii GrayCommon name: Patterson locoweedToxin: seleniumHabitat: dry plains and hillsides, in alkaline or sele-niferous soilsAnimals affected: cattle, sheep, horses

Astragalus pectinatus G. DonCommon name: tine-leaved milkvetchToxin: seleniumHabitat: variety of habitatsAnimals affected: cattle, sheep, horses

*Astragalus praelongus Sheld. var. praelongus Common name: stinking milkvetchToxin: seleniumHabitat: variety of habitatsAnimal affected: cattle, sheep, horses

* Major poisonous plant

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fabaceae (contd.)*Astragalus praelongus var. ellisiae (Rydb.) BarnebyCommon name: Ellis milkvetchToxin: seleniumHabitat: variety of habitats, widespreadAnimals affected: cattle, sheep, horses

Astragalus racemosus Pursh var. racemosusCommon name: alkali milkvetchToxin: seleniumHabitat: barren slopes, alluvial areas, alkaline soilsAnimals affected: cattle

Astragalus racemosus var. longisetus M.E. JonesCommon name: alkali milkvetchToxin: seleniumHabitat: eroded slopes, along streamsAnimals affected: cattle

Astragalus tephrodes GrayCommon name: silverline locoweedToxin: swainsonineHabitat: rocky slopes to sandy plainsAnimals affected: cattle, sheep, horses

*Astragalus thurberi GrayCommon name: Thurber milkvetchToxin: alkaloid (locoine)Habitat: plains, valleys, open slopesAnimals affected: cattle, sheep, horses

Cassia fasiculata Michx.Common name: partridge-peaToxin: unknownHabitat: dry fields and hillsidesAnimals affected: cattle, sheep, horses

Crotalaria sagittalis L.Common name: rattlebox, crotalariaToxin: unknownHabitat: sandy soil near streamsAnimals affected: horses

Lathyrus polymorphus Nutall subsp. incanus (J.G. Sm. & Rydb.) C.L. Hitchc.Common name: wild pea

Toxin: alpha-, gamma-diaminobutyric acidHabitat: dry plains, sandy banks, washesAnimals affected: horses

Lotus corniculatus L.Common name: birdsfoot trefoilToxin: cyanogenetic glycosideHabitat: sandy roadsidesAnimals affected: cattle, sheep, horses

*Lupinus alpestris A. Nels.Common name: lupine, bluebonnetToxin: alkaloidsHabitat: mountainsAnimals affected: cattle, sheep

*Lupinus argenteusCommon name: silvery lupineToxin: alkaoidsHabitat: meadows, open woodsAnimals affected: cattle, sheep, deer

*Lupinus caudatus Kell.Common name: Kellogg’s spurred lupine, tailcut lupineToxin: alkaloidsHabitat: exposed hillsidesAnimals affected: cattle

Medicago hispida Gaertn.Common name: burcloverToxin: photosensitization compoundsHabitat: waste areasAnimals affected: cattle, sheep, swine

Medicago sativa L.Common name: alfalfa, lucerneToxin: saponin, photosensitization compoundsHabitat: cultivated and escapingAnimals affected: cattle, sheep, chicks, swine

Melilotus albus Desv.Common name: white sweetcloverToxin: dicoumarinHabitat: waste areas, fieldsAnimals affected: cattle

* Major poisonous plant

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fabaceae (contd.)*Melilotus officinalis Lam.Common name: yellow sweetcloverToxin: dicoumarinHabitat: waste areas, fieldsAnimals affected: cattle, sheep, horses

*Oxytropis lambertii PurshCommon name: Lambert’s crazyweedToxin: unknown alkaloid, produces locoismHabitat: plains, mountain slopesAnimals affected: cattle, sheep, horses

*Oxytropis sericea Torr. & GrayCommon name: white loco, silky crazyweedToxin: alkaloids, produces locoismHabitat: open slopes, widespreadAnimals affected: cattle, sheep, horses

Pisum sativum L.Common name: garden peaToxin: unknownHabitat: gardensAnimals affected: cattle, sheep

Caesalpinia gilliesii (Wallich ex Hooker) Wallich ex D. DietrichCommon name: bird of paradiseToxin: unknown, green seed pods are gastrointestinal irritantsHabitat: around dwelling sites, waste areasAnimals affected: cattle

Prosopis glandulosa Torr.Common name: mesquiteToxin: unknown, may cause a nutritional deficiencyHabitat: plains, prairies, river valleysAnimals affected: cattle

Psoralea argophylla PurshCommon name: scurf peaToxin: unknownHabitat: plains and hillsAnimals affected: cattle, sheep

Psoralea tenuiflora PurshCommon name: scurf pea, Indian turnipToxin: unknown

Habitat: dry plains, low hillsAnimals affected: cattle, horses

Robinia pseudoacacia L.Common name: black locustToxin: unknownHabitat: along roadsides, escaped from cultivationAnimals affected: cattle, sheep, horses, poultry

Sophora secundiflora (Ort.) Lag.Common name: mescal bean, frijolitoToxin: alkaloidsHabitat: along limestone bluffs, gravelly outwashesAnimals affected: cattle, sheep, goats

Sophora sericea Nutt.Common name: silky sophoraToxin: alkaloidsHabitat: dry fields and plainsAnimals affected: horses

Thermopsis montana Nutt.Common name: mountain golden peaToxin: alkaloidsHabitat: mountain valleys and clearingsAnimals affected: cattle

Thermopsis rhombifolia Rich.Common name: prairie thermopsisToxin: alkaloidsHabitat: dry, sandy soils of hills and plainsAnimals affected: cattle, horses

Trifolium hybridum L.Common name: alsike cloverToxin: photosensitizing compoundHabitat: meadows, waste areasAnimals affected: cattle, sheep, horses, swine

Trifolium pratense L.Common name: red cloverToxin: unknownHabitat: fields and waste areasAnimals affected: cattle, sheep, horses

Trifolium repens L.Common name: white cloverToxin: cyanogenetic glycoside

* Major poisonous plant

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fabaceae (contd.)Habitat: fields and waste areasAnimals affected: newborn pigs

Vicia villosa RothCommon name: hairy vetch, wintervetchToxin: photosensitizing compoundHabitat: cultivated areasAnimals affected: cattle, horses

fagaceae*Quercus gambelii Nutt.Common name: GambeloakToxin: tanninsHabitat: canyons and mountain slopesAnimals affected: cattle, sheep, goats

*Quercus havardii Rydb.Common name: Havard shinoak, shinneryToxin: tanninsHabitat: sandy plainsAnimals affected: cattle, sheep

fumariaceae*Corydalis aurea Willd.Common name: golden corydalisToxin: alkaloidsHabitat: damp slopes and plainsAnimals affected: cattle, sheep

GentianaceaeCentaurium calycosum Fern.Common name: mountain pinkToxin: unknownHabitat: boggy or marshy placesAnimals affected: sheep, goats

Hypericaceae Hypericum formosum H.B.K.Common name: southwestern St. John’s wortToxin: photosensitizing compoundsHabitat: moist soil in damp meadowsAnimals affected: cattle, sheep, horses, goats

Iridaceae Iris missouriensis Nutt.Common name: Rocky Mountain irisToxin: unknownHabitat: open meadows in the higher mountainsAnimals affected: calves

Juncaginaceae*Triglochin maritima L.Common name: arrowgrassToxin: hydroqanic acidHabitat: marshy groundAnimals affected: cattle, sheep

*Triglochin palustris L.Common name: arrowgrassToxin: hydroqanic acidHabitat: marshy groundAnimals affected: cattle, sheep

lamiaceaeLamium amplexicaule L.Common name: henbit, dead nettleToxin: unknownHabitat: waste areasAnimals affected: cattle, sheep, horses

Salvia reflexa Hornem.Common name: annual sage, mintweedToxin: nitratesHabitat: rocky slopes, open woodsAnimals affected: cattle

liliaceaeAsparagus officinalis L.Common name: asparagusToxin: unknown compound in fruitsHabitat: valleys, roadsides, loose or sandy soilsAnimals affected: cattle and dairy cattle

*Veratrum californicum DurandCommon name: false hellebore, cornlilyToxin: alkaloidsHabitat: moist meadows in the mountainsAnimals affected: cattle, sheep, fowl

*Zigadenus venenosus PurshCommon name: death camasToxin: alkaloidsHabitat: wooded slopes in the mountainsAnimals affected: cattle, horses, swine, fowl

*Zigadenus gramineus Rydb.Common name: death camasToxin: alkaloidsHabitat: wooded slopes and open groundAnimals affected: cattle, sheep, horses

* Major poisonous plant

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Moraceae Maclura pomifera SchneidCommon name: Osage orangeToxins: unknown compounds in fruitHabitat: waste areas and arroyosAnimals affected: cattle, sheep, horses

oxalidaceaeOxalis corniculata L.Common name: creeping woodsorrel Toxin: oxalates Habitat: moist waste areas, often in lawns Animals affected: sheep

Papaveraceae Argemone mexicana L. Common name: Mexican poppyToxin: alkaloids Habitat: waste areasAnimals affected: cattle, sheep, horses, fowl

Argemone polyanthemos (Fedde) G. OwnbeyCommon name: prickly poppyToxin: alkaloidsHabitat: dry plains, waste areasAnimals affected: cattle, sheep, horses, fowl

Papaver nudicaule L. var. radicatum (Rottb.) DC.Common name: Iceland poppyToxin: alkaloidsHabitat: open slopes and summitsAnimals affected: cattle, sheep, horses

Papaver somniferum L.Common name: common poppyToxin: alkaloidsHabitat: ornamentalAnimals affected: cattle, sheep, horses

PinaceaePinus ponderosa Laws.Common name: Western yellow pine, ponderosa pineToxin: unknown compounds in leavesHabitat: mountain areasAnimals affected: cattle

liliaceae (contd.)*Zigadenus paniculatus (Nutt.) WatsCommon name: death camasToxin: alkaloidsHabitat: open grassy or rocky plains and hillsAnimals affected: cattle, horses, swine

linaceaeLinum neomexicanum GreeneCommon name: New Mexico yellow flaxToxin: saponin, glycosideHabitat: wooded mountain slopesAnimals affected: cattle

Linum usitatissimum L.Common name: flaxToxin: cyanogenetic glycosideHabitat: waste areas around cultivated areasAnimals affected: cattle

loranthaceae Phoradendron flavescens (Pursh) Nutt.Common name: mistletoeToxin: pressor amines, phenylethylamine, tyramineHabitat: parasitic on cottonwood and other decidu-ous treesAnimals affected: cattle

MalvaceaeGossypium barbadense L.Common name: sea-island cottonToxin: gossypol in seedsHabitat: cultivatedAnimals affected: cattle, sheep, horses

Malva parviflora L.Common name: mallow, cheeseweedToxin: fatty acids (malvalic and sterculic)Habitat: waste areasAnimals affected: cattle, sheep, horses

MeliaceaeMelia azedarach L.Common name: chinaberry treeToxin: resins, especially in fruitsHabitat: waste areas, ornamentalAnimals affected: cattle, sheep, horses

* Major poisonous plant

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PoaceaeAgropyron cristatum (L.) Gaertn.Common name: wheatgrassToxin: ergot infestation of seedheadsHabitat: rangeland and pasturesAnimals affected: cattle, sheep, horses, humans

Aristida spp.Common name: red three-awnToxin: awns are mechanically injuriousHabitat: plains and rocky slopesAnimals affected: cattle, sheep, horses

Avena fatua L.Common name: wild oatsToxin: nitratesHabitat: cultivated land and waste areasAnimals affected: cattle, sheep, horses

Avena sativa L.Common name: cultivated oatsToxin: nitrates, photosensitizing compounds, grass tetanyHabitat: open ground, grasslands, waste areasAnimals affected: cattle, sheep, horses

Bouteloua spp.Common name: grama grassesToxin: low levels of cyanideHabitat: plainsAnimals affected: cattle

Bromus diandrus RothCommon name: ripgut bromeToxin: mechanical injury from mature awnsHabitat: weedy groundAnimals affected: cattle, sheep

Bromus inermis Leyss.Common name: smooth bromeToxin: ergot infestation of seed headsHabitat: mountain slopes and meadowsAnimals affected: cattle, sheep, horses

Bromus rubens L.Common name: foxtail chess, red bromeToxin: mechanical injury from mature awnsHabitat: dry hills and waste areasAnimals affected: cattle, sheep

Bromus tectorum L.Common name: cheatgrass, down cheatToxin: mechanical injury from mature awns; may also cause ergot poisoningHabitat: roadsides and waste areasAnimals affected: cattle

Cynodon dactylon (L.) Pers.Common name: BermudagrassToxin: photosensitizing compound, hayfeverHabitat: waste areas; widespreadAnimals affected: cattle

Elymus spp.Common name: wild ryeToxin: ergot infestationHabitat: mountain slopes, plainsAnimals affected: cattle

Eragrostis cilianensis (All.) Lutati ex JanchenCommon name: lovegrass, stinkgrassToxin: unknownHabitat: cultivated or waste areasAnimals affected: horses

Festuca arundinacea SchreberCommon name: tall fescueToxin: alkaloids, fescue footHabitat: pasturesAnimals affected: cattle

Glyceria striata (Lam.) Hitchc.Common name: fowl mannagrassToxin: cyanogenetic compoundsHabitat: plains and foothillsAnimals affected: cattle, sheep, horses

Hilaria jamesii (Torr.) Benth.Common name: galletaToxin: ergot infestation of seedheadsHabitat: plains and foothillsAnimals affected: cattle, sheep, horses

Hilaria mutica (Buckl.) Benth.Common name: tobosaToxin: ergot infestation of seedheadsHabitat: plains and foothillsAnimals affected: cattle, sheep, horses

* Major poisonous plant

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Poaceae (contd.)Hordeum jubatum L.Common name: foxtail barleyToxin: mechanical injury from mature awnsHabitat: plains and open slopesAnimals affected: cattle, sheep, horses

Hordeum vulgare L.Common name: barleyToxin: mechanical injury from mature awnsHabitat: waste areasAnimals affected: cattle, swine, dogs, poultry

Lolium perenne L.Common name: perennial ryegrassToxin: ergot infestation of seed headsHabitat: meadows, waste areasAnimals affected: cattle

Panicum antidotale Retz.Common name: blue panicumToxin: nitratesHabitat: rangelandsAnimals affected: cattle

Panicum capillare L.Common name: witchgrassToxin: nitratesHabitat: roadsides, waste placesAnimals affected: cattle

Panicum coloratum L.Common name: KleinegrassToxin: photosensitivityHabitat: pasturesAnimals affected: sheep

Paspalum dilatatum Poir.Common name: dallisgrassToxin: ergot infestation of seed headsHabitat: irrigated pastures, moist disturbed areasAnimals affected: cattle, sheep, horses

Poa pratensis L.Common name: Kentucky bluegrassToxin: ergot infestation of seed headsHabitat: lawns, pastures, meadowsAnimals affected: cattle, sheep, horses

Secale cereale L.Common name: ryeToxin: ergot infestation of seed headsHabitat: cultivatedAnimals affected: cattle, sheep, horses, humans

Setaria lutescens (Wiegel) Hubb.Common name: yellow bristlegrassToxin: mechanically injurious (rare)Habitat: waste areasAnimals affected: cattle

Sorghum bicolor (L.) MoenchCommon name: common sorghum, miloToxin: cyanideHabitat: waste areas, cultivatedAnimals affected: cattle, sheep, horses

*Sorghum halepense (L.) Pers.Common name: JohnsongrassToxin: cynanideHabitat: waste areas, cultivated fieldsAnimals affected: cattle, sheep, horses

Stipa comata Trin. Rupr.Common name: needle-and-threadToxin: mechanical injury from mature awnsHabitat: open slopesAnimals affected: cattle, sheep, horses

Stipa neomexicana (Thurb.) Scribn.Common name: New Mexico feathergrassToxin: mechanical injury from mature awnsHabitat: dry hillsAnimals affected: cattle, sheep, horses

Stipa robusta (Vasey) Scribn.Common name: sleepygrassToxin: unknown narcoticHabitat: open slopes, northern to south-central New MexicoAnimals affected: horses

Zea mays L.Common name: common maizeToxin: nitratesHabitat: cultivatedAnimals affected: cattle

* Major poisonous plant

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Toxin: oxalatesHabitat: waste areas, cultivated areasAnimals affected: sheep

Primulaceae Anagallis arvensis L.Common name: pimpernelToxin: unknownHabitat: waste areasAnimals affected: sheep

ranunculaceae *Aconitum columbianum Nutt.Common name: monkshoodToxin: alkaloidsHabitat: moist ground, often along streamsAnimals affected: cattle, sheep, horses

Actea arguta Nutt.Common name: baneberryToxin: irritant oilHabitat: woodsAnimals affected: cattle, sheep, horses, humans

Anemone patens L.Common name: pasque flowerToxin: glycosideHabitat: open meadowsAnimals affected: sheep

Caltha leptosepala DC.Common name: elkslip, March marigoldToxin: glycosideHabitat: wet meadows, boggy groundAnimals affected: cattle, sheep

*Delphinium barbeyi Huth.Common name: Barbey larkspur, tall larkspurToxin: alkaloidsHabitat: open meadowsAnimals affected: cattle, occasionally sheep

*Delphinium nelsonii GreeneCommon name: Nelson larkspurToxin: alkaloidsHabitat: dry plainsAnimals affected: cattle, sheep, horses

*Delphinium occidentale Wats.Common name: larkspur

PolygalaceaePolygala sanguinea (L.) FarwellCommon name: milkwort, snakerootToxin: irritant drugHabitat: plainsAnimals affected: horses

PolygonaceaeBeta vulgaris L.Common name: beet, sugar beetToxin: oxalates, nitratesHabitat: cultivatedAnimals affected: cattle

Fagopyrum sagittatum Gilib.Common name: buckwheatToxin: primary photosensitizerHabitat: waste areas, roadsidesAnimals affected: cattle, sheep, horses, goats, swine, fowl

Rheum rhaponticum L.Common name: rhubarbToxin: oxalic acid in the leaf bladesHabitat: cultivatedAnimals affected: cattle, sheep

Rumex acetosella L.Common name: sheep sorrel, dockToxin: oxalates in the leaf bladesHabitat: disturbed placesAnimals affected: sheep

Rumex crispus L.Common name: curlyleaf dockToxin: oxalatesHabitat: cultivated fields, waste areasAnimals affected: sheep

Polypodiaceae*Pteridium aquilinum (L.) Kuhn.Common name: bracken fernToxin: thiaminaseHabitat: open woods and clearings in the mountainsAnimals affected: cattle, sheep, horses

Portulacaceae Portulaca oleracea L.Common name: common purslane* Major poisonous plant

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Prunus persica BatschCommon name: peachToxin: cyanogenetic glycoside, especially in seeds (pits)Habitat: cultivatedAnimals affected: cattle, sheep, horses

*Prunus serotina Ehrh.Common name: southwestern chokecherryToxin: cyanogenetic glycosideHabitat: along streamsAnimals affected: cattle, sheep, horses

*Prunus virginiana L.Common name: chokecherryToxin: cyanogenetic glycosideHabitat: moist canyons and slopesAnimals affected: cattle, sheep

santalaceaeComandra umbellata (L.) Nutt.Common name: bastard toadflaxToxin: alkaloids, glycosides, seleniumHabitat: plains and forested slopes; parasitic on other plantsAnimals affected: cattle, sheep, horses

scrophulariaceae Castilleja spp.Common name: paintbrushesToxin: seleniumHabitat: foothills and plainsAnimals affected: cattle

sinopteridaceaeDryopteris filix-mas (L.) SchottCommon name: malefernToxin: thiaminaseHabitat: damp, rocky places, often along streamsAnimals affected: horses

*Notholaena sinuata (Lag.) Kaulf. var. cochisenis (Goodding) Weath.Common name: Jimmy fern, cloak fernToxin: unknown, passed through the milkHabitat: dry, rocky areas, along canyon wallsAnimals affected: sheep

ranunculaceae (contd.)Toxin: alkaloidsHabitat: dry slopes in oak scrubAnimals affected: cattle, sheep, horses

*Delphinium robustum Rydb.Common name: larkspurToxin: alkaloidsHabitat: mountain meadowsAnimals affected: cattle, sheep, horses

*Delphinium virescens Nutt.Common name: larkspurToxin: alkaloidsHabitat: dry plains and hillsAnimals affected: cattle, sheep, horses

Ranunculus cymbalaria PurchCommon name: alkali buttercup, trailing buttercupToxin: glycosideHabitat: wet groundAnimals affected: cattle, sheep, horses

Ranunculus sceleratus L.Common name: crowfoot, buttercupToxin: glycosideHabitat: marshy groundAnimals affected: cattle, sheep, horses

rosaceae*Cercocarpus montanus Raf.Common name: mountain mahoganyToxin: cyanogenetic glycosidesHabitat: dry hillsidesAnimals affected: cattle

Malus sylvestris Mill.Common name: appleToxin: cyanide in leavesHabitat: cultivatedAnimals affected: cattle, horses, mules

Prunus armeniaca L.Common name: apricotToxin: cyanogenetic glycoside, especially in seeds (pits)Habitat: cultivatedAnimals affected: cattle, sheep, horses

* Major poisonous plant

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solanaceae*Datura stramonium L.Common name: JimsonweedToxin: alkaloidsHabitat: waste or cultivated groundAnimals affected: cattle, sheep, horses, swine, mules, chickens, humans

*Datura wrightii Regel.Common name: datura, thornappleToxin: alkaloidsHabitat: mesas and waste groundsAnimals affected: cattle, sheep, horses, swine, mules, chickens, humans

Hyoscyamus niger L.Common name: henbaneToxin: alkaloidsHabitat: moist roadsidesAnimals affected: cattle, sheep, fowl

Lycium halimifolium Mill.Common name: matrimony vineToxin: unknownHabitat: dry hills and plainsAnimals affected: calves, sheep

Lycopersicon esculentum Mill.Common name: tomatoToxin: alkaloids in leaves and vinesHabitat: cultivatedAnimals affected: cattle, swine

Nicotiana attenuata S. Wats.Common name: coyote tobaccoToxin: nicotineHabitat: sandy ground near streams and washesAnimals affected: cattle, sheep, horses, swine

Nicotiana glauca GrahamCommon name: tree tobaccoToxin: nicotineHabitat: along desert streams and washesAnimals affected: cattle, sheep, horses

Nicotiana trigonophylla DunalCommon name: desert tobaccoToxin: nicotineHabitat: desert canyons, washesAnimals affected: cattle, sheep, horses

Physalis virginiana Mill. var. sonora (Torr.) WaterfallCommon name: groundcherryToxin: unknownHabitat: moist ground, widespreadAnimals affected: sheep

*Solanum elaeagnifolium Cav.Common name: silverleaf nightshade, horsenettleToxin: glycoalkaloidsHabitat: shaded slopes or waste areasAnimals affected: cattle, sheep

Solanum nigrum L.Common name: black nightshadeToxin: glycoalkaloidsHabitat: shaded slopes or waste areasAnimals affected: cattle, sheep, horses

Solanum rostratum Dunal.Common name: buffaloburToxin: glycoalkaloidsHabitat: plains and waste areasAnimals affected: cattle, swine

Solanum sarachoides Sendt. Common name: hairy nightshadeToxin: glycoalkaloidsHabitat: waste areasAnimals affected: cattle, sheep, horses

Solanum triflorum Nutt.Common name: cutleaf nightshadeToxin: glycoalkaloidsHabitat: plains, roadsides, streambedsAnimals affected: cattle, horses

typhaceaeTypha latifolia L.Common name: cattailToxin: hayfeverHabitat: marshes, pondsAnimals affected: horses

Urtica gracilis Ait.Common name: stinging nettleToxin: stinging hairs cause dermatitis, nitratesHabitat: rich damp soil in thickets in mountainsAnimals affected: horses

* Major poisonous plant

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VerbenaceaeAloysia wrightii (Gray) HellerCommon name: whitebrushToxin: unknownHabitat: dry, rocky slopes, often on limestone soilsAnimals affected: horses

Zygophyllaceae Kallstroemia hirsutissima VailCommon name: hairy caltropToxin: unknownHabitat: dry plains, widespreadAnimals affected: cattle, sheep, goats

Peganum harmala L.Common name: African rueToxin: alkaloidsHabitat: southern dry plainsAnimals affected: cattle

*Tribulus terrestris L.Common name: puncturevine, goatheadToxin: nitrates, photosensitizing compound, saponinsHabitat: disturbed areasAnimals affected: sheep

references

Fuller, T.C., and E. McClintock. 1986. Poisonous plants of California. Berkely: University of California Press.

James, L.F., R.F. Keeler, A.E. Johnson, M.C. Williams, E.H. Cronin, and J.D. Olsen. 1980. Plants poison-ous to livestock in the western states (Inf. Bul. 415). Washington, D.C.: U.S. Department of Agriculture.

Kingsbury, J.M. 1964. Poisonous plants of the United States and Canada. Upper Saddle River, NJ: Prentice-Hall, Inc.

Norris, J.J., K.A. Valentine. 1957. Principle livestock-poi-soning plants of New Mexico ranges (Circular 274). Las Cruces, NM: New Mexico State University Coopera-tive Extension Service.

Schmutz, E.M., B.N. Freeman, and R.E. Reed. 1968. Livestock-poisoning plants of Arizona. Tucson: Univer-sity of Arizona Press.

* Major poisonous plant

A

Acacia constricta 11Acacia greggii 11Achillea millefolium 5Aconitum columbianum 19Actea arguta 19African rue 22Agave lechuguilla 4Agropyron cristatum 17Agrostemma githago 9Alfalfa 13Alkali buttercup 20Alkali milkvetch 13Aloysia wrightii 22Alsike clover 14Amaranthus palmeri 4Amaranthus retroflexus 4Amsinckia intermedia 8

Anagallis arvensis 19Anemone patens 19Annual goldeneye 8Annual psathyrotes 7Annual sage 15Anthemis cotula 5Apium graveolens 4Apocynum androsaemifolium 4Apocynum cannabinum 4Apple 20Apricot 20Argemone mexicana 16Argemone polyanthemos 16Aristida spp. 17Arrowgrass 15Artemisia filifolia 5Artemisia spinescens 5Asclepias asperula 5

Index to GenerIc And coMMon nAMes

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Asclepias incarnata 5Asclepias latifolia 5Asclepias pumila 5Asclepias speciosa 5Asclepias subverticillata 5Asclepias verticillata 5Asparagus 15Asparagus officinalis 15Aster 5, 6Aster adscendens 5Aster coerulescens 5Aster commutatus 6Aster ericoides 6Aster glaucoides 6Aster laevis 6Aster occidentalis 6Aster pauciflorus 6Astragalus albulus 11Astragalus allochrous var. allochrous 11Astragalus allochrous var. playanus 11Astragalus bisulcatus var. bisulcatus 12Astragalus bisulcatus var. haydenianus 12Astragalus canadensis 12Astragalus confertiflorus 12Astragalus drummondii 12Astragalus emoryanus 12Astragalus flavus 12Astragalus lentiginosus var. diphysus 12Astragalus lentiginosus var. lentiginosus 12Astragalus mollissimus var. earlei 12Astragalus mollissimus var. mollissimus 12Astragalus nothoxys 12Astragalus oocalycis 12Astragalus pattersonii 12Astragalus pectinatus 12Astragalus praelongus var. praelongus 12Astragalus praelongus var. ellisiae 13Astragalus racemosus var. longisetus 13Astragalus racemosus var. racemosus 13Astragalus tephrodes 13Astragalus thurberi 13Atriplex canescens 10Atriplex nuttallii var. cuneata 10Atriplex rosea 10Avena fatua 17Avena sativa 17

B

Baccharis pteronioides 6Bahia 6Bahia oppositifolia 6Baileya multiradiata 6

Baneberry 19Barbarea vulgaris 9Barbey larkspur 19Barilla 10Barley 18Bassia 10Bassia hyssopifolia 10Bastard toadflax 20Beaked milkvetch 12Beargrass 4Beet 19Bermudagrass 17Berula erecta 4Beta vulgaris 19Bird of paradise 14Birdsfoot trefoil 13Bitter rubberweed 7Bitterweed 7Black-eyed Susan 8Black locust 14Black mustard 9Black nightshade 21Bluebonnet 13Blue loco 12Blue panicum 18Bouncing bet 10Bouteloua spp. 17Bracken fern 19Brassica hirta 9Brassica kaber 9Brassica nigra 9Broadleaf milkweed 5Bromus diandrus 17Bromus inermis 17Bromus rubens 17Bromus tectorum 17Broom groundsel 8Broom snakeweed 7Broomweed 6Buckwheat 19Bud sagebrush 5Buffalobur 21Bulrush 10Burclover 13Burrowweed 7Buttercup 20

C

Caesalpinia gilliesii 14Caltha leptosepala 19Canada milkvetch 12Cannabis sativa 9

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Carelessweed 4Cassia fasiculata 13Castilleja spp. 20Catclaw acacia 11Cattail 21Celery 4Centaurea repens 6Centaurea solstitialis 6Centaurium calycosum 15Cercocarpus montanus 20Charlock 9Cheatgrass 17Cheeseweed 16Chenopodium album 10Chenopodium ambrosioides 10Chenopodium glaucum 10Chinaberry tree 16Chokecherry 20Chrysothamnus nauseosus 6Cibola milkvetch 11Cicuta maculata 4Cloak fern 20Cocklebur 8Colorado rubberweed 7Comandra umbellata 20Common groundsel 8Common maize 18Common poppy 16Common purslane 19Common sorghum 18Common tansy 8Coneflower 7Conium maculatum 4Conyza 6Conyza coulteri 6Copperweed 7Corn cockle 9Cornlily 15Corydalis aurea 15Cow cockle 10Coyote tobacco 21Creeping woodsorrel 16Crotalaria 13Crotalaria sagittalis 13Croton texensis 11Crowfoot 20Cultivated oats 17Curlycup gumweed 6Curlyleaf dock 19Cutleaf nightshade 21Cynodon dactylon 17Cynoglossum officinale 8

D

Dallisgrass 18Datura 21Datura stramonium 21Datura wrightii 21Daucus carota 4Dead nettle 15Death camas 15, 16Delphinium barbeyi 19Delphinium nelsonii 19Delphinium occidentale 19Delphinium robustum 20Delphinium virescens 20Descurainia pinnata 9Desert baileya 6Desert marigold 6Desert tobacco 21Dock 19Dogbane 4Dog fennel 5Down cheat 17Drummond milkvetch 12Drymaria pachyphylla 9Drymary 9Dryopteris filix-mas 20

E

Elkslip 19Ellis milkvetch 13Elymus spp. 17Emory milkvetch 12Equisetum arvense 11Equisetum hiemale 11Equisetum laevigatum 11Eragrostis cilianensis 17Euphorbia 11Euphorbia albomarginata 11Euphorbia esula 11Euphorbia maculata 11Euphorbia marginata 11Euphorbia prostrata 11Eyebane 11

F

Fagopyrum sagittatum 19False hellebore 15Festuca arundinacea 17Fewheaded aster 6Fiddleneck 8Field pennycress 9Flax 16

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Flourensia cernua 6Four-wing saltbush 10Fowl mannagrass 17Foxtail barley 18Foxtail chess 17Frijolito 14

G

Galleta 17Gambeloak 15Garden pea 14Glyceria striata 17Goathead 22Golden corydalis 15Golden glow 7Goosefoot 10Gossypium barbadense 16Grama grasses 17Gray aster 6Greasewood 10Grindelia squarrosa 6Groundcherry 21Gutierrezia microcephala 6Gutierrezia sarothrae 7

H

Hairy caltrop 22Hairy nightshade 21Hairy vetch 15Halfmoon locoweed 11Halogeton 10Halogeton glomeratus 10Haplopappus tenuisectus 7Havard shinoak 15Helenium autumnale 7Helenium hoopesii 7Helenium microcephalum 7Hemp dogbane 4Henbane 21Henbit 15Hilaria jamesii 17Hilaria mutica 17Hordeum jubatum 18Hordeum vulgare 18Horsebrush 8Horsenettle 21Horsetail 11Hound’s tongue 8Hymenoxys odorata 7Hymenoxys richardsonii 7Hyoscyamus niger 21Hypericum formosum 15

I

Iceland poppy 16Indian turnip 14Inkweed 9Iris missouriensis 15Ironweed 8Isocoma wrightii 7

J

Jackass clover 9Jimmy fern 20Jimmyweed 7Jimsonweed 21Johnsongrass 18

K

Kallstroemia hirsutissima 22Kellogg’s spurred lupine 13Kentucky bluegrass 18Kleinegrass 18Kochia 10Kochia scoparia 10

L

Lactuca serriola 7Lambert’s crazyweed 14Lambsquarter 10Lamium amplexicaule 15Larkspur 19, 20Lathyrus polymorphus var. incanus 13Leafy spurge 11Lechuguilla 4Linum neomexicanum 16Linum usitatissimum 16Lobelia cardinalis 9Locoweed 12Lolium perenne 18Lotus corniculatus 13Lovegrass 17Low whorled milkweed 5Lucerne 13Lupine 13Lupinus alpestris 13Lupinus argenteus 13Lupinus caudatus 13Lycium halimifolium 21Lycopersicon esculentum 21

M

Maclura pomifera 16Malefern 20

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Mallow 16Malus sylvestris 20Malva parviflora 16March marigold 19Marijuana 9Matchbrush 7Matchweed 6Matrimony vine 21Mayweed 5Medicago hispida 13Medicago sativa 13Melia azedarach 16Melilotus albus 13Melilotus officinalis 14Mescal bean 14Mesquite 14Mexican elder 9Mexican poppy 16Milkwort 19Milo 18Mintweed 15Mistletoe 16Monkshood 19Mountain golden pea 14Mountain mahogany 20Mountain pink 15

N

Needle-and-thread 18Nelson larkspur 19Nerium oleander 5New Mexico feathergrass 18New Mexico yellow flax 16Nicotiana attenuata 21Nicotiana glauca 21Nicotiana trigonophylla 21Nolina microcarpa 4Nolina texana 4Notholaena sinuata var. cochisenis 20Nuttall saltbush 10

O

Oakleaf goosefoot 10Oleander 5Orange sneezeweed 7Osage orange 16Oxalis corniculata 16Oxytenia acerosa 7Oxytropis lambertii 14Oxytropis sericea 14

P

Paintbrushes 20Panicum antidotale 18Panicum capillare 18Panicum coloratum 18Papaver nudicaule var. radicatum 16Papaver somniferum 16Paperflower 7Parsnip 4Partidge-pea 13Paspalum dilatatum 18Pasque flower 19Pastinaca sativa 4Patterson locoweed 12Peach 20Peganum harmala 22Perennial ryegrass 18Perennial snakeweed 6Phoradendron flavescens 16Physalis virginiana var. sonora 21Pigweed 4Pimpernel 19Pingue 7Pinus ponderosa 16Pisum sativum 14Plains bahia 6Plains whorled milkweed 5Poa pratensis 18Poison hemlock 4Poison ivy 4Poison suckleya 10Polygala sanguinea 19Ponderosa pine 16Portulaca oleracea 19Prairie thermopsis 14Prickly poppy 16Prince’s plume 9Prosopis glandulosa 14Prunus armeniaca 20Prunus persica 20Prunus serotina 20Prunus virginiana 20Psathyrotes annua 7Psilostrophe sparsiflora 7Psilostrophe tagetinae 7Psoralea argophylla 14Psoralea tenuiflora 14Pteridium aquilinum 19Puncturevine 22

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Q

Queen Ann’s lace 4Quercus gambelii 15Quercus havardii 15

R

Ranunculus cymbalaria 20Ranunculus sceleratus 20Raphanus raphanastrum 9Rattlebox 13Rattleweed 12Rayless goldenrod 7Red brome 17Red clover 14Red orache 10Redroot amaranth 4Red shadscale 10Red three-awn 17Reverchonia 11Reverchonia arenaria 11Rheum rhaponticum 19Rhubarb 19Riddell’s groundsel 8Ripgut brome 17Robinia pseudoacacia 14Rocky Mountain iris 15Rocky Mountain red elder 9Rough milkweed 5Rubber rabbitbrush 6Rubberweed 7Rudbeckia hirta 8Rudbeckia laciniata 7Rumex acetosella 19Rumex crispus 19Russian knapweed 6Russian thistle 10Rye 18

S

Sacahuista 4Salsola tragus 10Salvia reflexa 15Sambucus mexicana 9Sambucus microbotrys 9Sand sagebrush 5Saponaria officinalis 10Saponaria vaccaria 10Sarcobatus vermiculatus 10Sartwellia 8Sartwellia flaveriae 8Scirpus americanus 10

Scouring rush 11Scurf pea 14Sea-island cotton 16Secale cereale 18Senecio flaccidus 8Senecio riddellii 8Senecio spartioides 8Senecio vulgaris 8Setaria lutescens 18Sheep sorrel 19Shinnery 15Showy milkweed 5Sideranthus grindelioides 8Silky crazyweed 14Silky sophora 14Silverleaf nightshade 21Silverline locoweed 13Silvery lupine 13Sium suave 4Sleepygrass 18Smooth aster 6Smooth brome 17Smooth horsetail 11Snakeroot 19Snakeweed 6, 7Sneezeweed 7Snow-on-the-mountain 11Soapwort 10Solanum elaeagnifolium 21Solanum nigrum 21Solanum rostratum 21Solanum sarachoides 21Solanum triflorum 21Sophora secundiflora 14Sophora sericea 14Sorghum bicolor 18Sorghum halepense 18Southwestern chokecherry 20Southwestern St. John’s wort 15Spider antelopehorn 5Spiny cocklebur 8Spiny horsebrush 8Spotted spurge 11Spreading dogbane 4Spurge 11Stanleya pinnata 9Stinging nettle 21Stinkgrass 17Stinking milkvetch 12Stipa comata 18Stipa neomexicana 18Stipa robusta 18

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New Mexico State University is an equal opportunity/affirmative action employer and educator. NMSU and the U.S. Department of Agriculture cooperating.

February 2010 Las Cruces, NM

Suckleya suckleyana 10Sugar beet 19Summer cypress 10Swamp milkweed 5

T

Tailcut lupine 13Tall fescue 17Tall larkspur 19Tanacetum vulgare 8Tansy mustard 9Tarbush 6Tetradymia canescens 8Tetradymia spinosa 8Texas croton 11Thermopsis montana 14Thermopsis rhombifolia 14Thimble weed 7Thlaspi arvense 9Thornapple 21Threadleaf groundsel 8Thurber milkvetch 13Tine-leaved milkvetch 12Tobosa 17Tomato 21Toxicodendron radicans 4Trailing buttercup 20Tree tobacco 21Tribulus terrestris 22Trifolium hybridum 14Trifolium pratense 14Trifolium repens 14Triglochin maritima 15Triglochin palustris 15Tumbleweed 10Turpentine weed 6, 7Two-grooved milkvetch 12Typha latifolia 21

U

Urtica gracilis 21

V

Veratrum californicum 15Vicia villosa 15Viguiera annua 8

W

Water hemlock 4Water parsnip 4Western aster 6Western cardinal flower 9Western whorled milkweed 5Western yellow pine 16Wheatgrass 17Whitebrush 22White clover 14Whitethorn acacia 11White loco 14White mustard 9White sweetclover 13Whorled milkweed 5Wild carrot 4Wild lettuce 7Wild oats 17Wild pea 13Wild radish 9Wild rye 17Wintervetch 15Wislizenia refracta 9Witchgrass 18Woolly locoweed 12Wooton locoweed 11

X

Xanthium spinosum 8Xanthium strumarium 8

Y

Yarrow 5Yellow bristlegrass 18Yellow milkvetch 12Yellow rocket 9Yellow starthistle 6Yellow sweetclover 14Yerba-de-pasmo 6

Z

Zea mays 18Zigadenus gramineus 15Zigadenus paniculatus 16Zigadenus venenosus 15