J. Range Manage. 55: 285-290 May 2002 Ecological relationships between poisonous and rangeland condition: A Review

MICHAEL H. RALPHS

Author is Rangeland Scientist, USDAJARS Poisonous Lab, Logan Utah 84341.

Abstract Resumen

In the past, excessive numbers of livestock on western U.S. En el pasado, el numeeo excesivo de ganado en los pastizales rangelands, reoccurring droughts, and lack of management del oeste de los Estados Unidos, las sequf as recurrentes y la falta resulted in retrogression of plant communities. Poisonous plants de manejo resultaron en la retrogresion de las comunidades veg- and other less palatable species increased with declining range etales. Las plantas toxicas y otras especies menos gustadas se condition and livestock were forced to eat these poisonous species incrementaron declinando la condicion del pastizal y el ganado because of a shortage of desirable forage, resulting in large, cata- fue forzado a comer estas especies toxicas debido a la escases de strophic losses. The level of management on most western range- forraje deseable, resultando en perdidas grandes y catastroficas. lands has improved during the last 60 years, resulting in marked Durante los ultimos 60 anos, el nivel de manejo de la mayoria de improvement in range condition; yet losses to poisonous plants los pastizales del oeste ha mejorado resultando en una marcada still occur, though not as large and catastrophic as in the past. mejoria de la condicion del pastizal; pero las perdidas por plan- Some poisonous species are major components of the pristine, tas toxicas todavia ocurren, aunque no son tan grandes ni cata- pre-European plant communities [tall larkspur (Delphinium bar- stroficas como en el pasado. Algunas especies toxicas son compo- beyi Huth), Veratrum californicum Durand, water hemlock nentes principales de las comunidades vegetales pristinas pre- (Cicuta douglasii (DC.)Coult. & Rose), bracken fern (Pteridium europeas ["Tall larkspur" (Delphinium barbeyi Huth), Veratrum aquilinum (L.) Kuhn), chokecherry (Prunus virginiana L.), californicum Durand, "Water hemlock" (Cicuta douglasii Ponderosa pine (Pinus ponderosa Lawson), and various oak (DC.)Coult.. & Rose), "Bracken fern" (Pteridium aquilinum (L.) Kuhn), "Chokecherry" species (Quercus spp.)]. Although populations of many poisonous (Prunus virginiana L.), "Ponderosa pine" seral increaser species have declined with better management, (Pinus ponderosa Lawson) y varias especies de encino (Quercus they are still components of plant communities and fluctuate spp.)]. Aunque las poblaciones de muchas de estas especies toxi- with changing precipitation patterns [locoweed (Astragalus and cas incresortrs han disminuido con un mejor manejo, ellas todavia son componentes de Oxytropis spp.), lupine (Lupinus spp.), death camas (Zigadenus las comunidades vegetales y fluc- spp.), snakeweed (Gutierrezia spp.), threadleaf groundsel tuan con los patrones cambiantes de precipitacion ["Locoweed" (Senecio longolobis Benth.), low larkspur (Delphinium nuttal- (Astragalus and Oxytropis spp.), "Lupine" (Lupinus spp.), "Death lianum Pritz.), timber milkvetch (Astragalus miser Dougl. ex camas" (Zigadenus spp.), "Snakeweed" (Gutierrezia spp.), Hook.), redstem peavine (A. emoryanus (Rydb.) Cory), western "Threadleaf groundsel" (Senecio longolobis Benth.), "Low lark- bitterweed ( odorata D.C.), orange sneezeweed spur" (Delphinium nuttallianum Pritz.), "Timber milkvetch" (Helenium hoopesii Gray), twin leaf senna (Cassia roemeriana (Astragalus miser Dougl. ex Hook.), "Redstem peavine" (A. Schelle), and white snakeroot (Eupatorium rugosum Houtt)]. emoryanus (Rydb.) Cory), "Western bitterweed" (Hymenoxys Many of the alien invader species are poisonous: [Halogeton odorata D.C.), "Orange sneezeweed" (Helenium hoopesii Gray), glomeratus (Bieb.) C.A. Mey, St. Johnswort (Hypericum perfora- "Twin leaf senna" (Cassia roemeriana Schelle) y "White snake- tum L.), poison hemlock (Conium maculatum L.), tansy ragwort root" (Eupatorium rugosum Houtt)]. Muchas de las especies (Senecio jacobaea L.), hounds tongue (Cynoglossum off icinale L.), invasoras extranjeras son toxicas: [Halogeton glomeratus (Bieb.) leafy spurge (Euphorbia esula L.), yellow star thistle (Centaurea C.A. Mey, "St. Johnswort" (Hypericum perforatum L.)," Poison hemlock" (Conium solstitialis L.) and other knapweeds (Centaurea spp.)]. Poisoning maculatum L.), "Tansy ragwort" (Senecio occurs when livestock consume these plants because they are jacobaea L.), "Hounds tongue" (Cynoglossum officinale L.), either relatively more palatable than the associated forage, or "Leafy spurge" (Euphorbia esula L.), "Yellow star thistle" from management mistakes of running short of desirable forage. (Centaurea solstitialis L.) y otras "Knapweeds" (Centaurea spp.)]. El envenenamiento ocurre cuando el ganado consume estas plan- tas porque ellas son de una gustocidad relativamente mayor que el forraje asociado o por errores de manejo durante escases de Key Words: Poisonous plants, rangeland condition, larkspur, forraje deseable. Delphinium spp., locoweed, Astragalus spp., Oxytropis spp., lupine, Lupinus spp., death camas, Zigadenus spp. Poisoning Related to Overgrazing in the Past Two factors contributed to the high incidence of poisonous plant problems on western U.S. rangelands: abundance of toxic plants, both in number of species and density of plants; and over- Manuscript 27 May 00. grazing. Western rangelands are extremely variable in topogra-

JOURNAL OF RANGE MANAGEMENT 55(3) May 285 Table 1. Poisonous plants found in physiographic regions and plant communities. occurred because there were too many livestock on the ranges, management was Great Plains and Prairies almost nil, and knowledge of poisonous Tall-grass prairie Short/Mid-grass prairie Oak/mesquite savanna plants was meager. White snakeroot Plains larkspur Bitterweed Rangelands today are in the best condi- Riddells groundsel Locoweed Twin leaf senna tion that they have been in for the last 100 Threadleaf groundsel Oak years (Box and Malechek 1987), due to Broom snakeweed and intensified range and live- Redstem peavine improved stock management. Knowledge of poiso- Southwest Deserts nous plants, their toxins and conditions of Sonoran Desert Desert grasslands Mohave Desert poisoning has increased. Thus, the inci- Garboncillo baileya dence of large, catastrophic losses has Mescal bean Rayless goldenrod Milkweed declined. The following is a chronological Red-stem peavine Broom snakeweed Coyotillo list of statements taken from the poisonous Wooly paperflower plant literature and prominent range man- Mountains agement text books illustrating the evolu- tion of the relationship between range con- Mountain brush Mt. big sagebrush Aspen l conifer dition and livestock poisoning: Orange sneezeweed camas larkspur Chokecherry Low larkspur Timber milkvetch Marsh (1913)-"Stock seldom eat poi- Oak Lupine False hellebore sonous plants by choice, but only Ponderosa pine when induced or compelled by the scarcity of other food or on overgrazed Colorado Plateau 1 Great Basin ranges." Salt desert shrub Sagebrush steppe Juniper I Pinyon Halogeton camas Stoddart and Smith (1943)- Greasewood Anderson larkspur Lupine "Poisonous plants cause great loss on Horsebrush Water hemlock Pingue western ranges. Losses are increasing in spite of increased knowledge con- phy, soils, and climate, resulting in very by major plants of that day: cerning poisonous plants and treatment diverse plant communities. Many of the 1. The loco habit is usually acquired dur- of poisoned animals." plant species contain toxins, and if eaten ing a season of short feed, when the is in sufficient quantity, would poison ani- locoweeds (Astragalus and Oxytropis Stoddart et al. (1949) "Poisoning natures' sign of a sick range." mals. Kingsbury (1964) described over spp.) are the most attractive form of 1,000 poisonous plants, found mostly in vegetation. Stoddart and Smith (1955)- "Losses the western US and Canada. 2. Larkspur (Delphinium spp.) poisoning have decreased measurably because Livestock poisoning became a signifi- is most likely to occur either during the stockmen have learned to recognize cant problem as settlers moved west and season of short feed, or on overgrazed poisonous species and have learned to their livestock encountered a vast array of areas; in either case the larkspur is the avoid them or to minimize damage poisonous plants (Table 1). The plains and most conspicuous form of vegetation to from them." prairies were fully stocked by the 1880's, attract the animals and is eaten in lieu et al. "Poisonous and the mountains and deserts by the turn of anything better. Stoddart ( 1975)- plants are normal components of range of the century. The number of livestock on 3. The roots of water hemlock (Cicuta ecosystems. Most losses can be avoid- western rangelands exceeded the biologi- douglasii (DC.)Coult.. & Rose) are ed by good management; others occur cal carrying capacity and management was picked up when there is little else to eat with such irregularity due to unpre- generally lacking. Retrogression of the and with disastrous results. dictable conditions that they constitute plant communities following misuse and 4. Successive bands of are driven hazard." reoccurring drought contributed to live- over the same trail until everything suit- an ever-present stock poisoning. Poisonous and other less able for food disappears, and then there Vallentine (1990) - "Prolonged palatable species increased as the more follow cases of poisoning from wild droughts and overgrazing sometimes desirable forage plants were heavily cherry [chokecherry (Prunus virginiana force livestock to eat harmful amounts grazed and died out, and animals were L.)]. On some trails there is an almost of poisonous plants. On good condi- other forage, forced, through shortage of continuous hedge of wild cherry, and tion ranges, poisonous plants are sub- to eat the poisonous species. the leaves are eaten as high as the sheep jected to intense competition from vig- The problem was sufficiently severe that can reach. orous, high producing forage plants, it became a national concern. The USDA 5. Sheep are sometimes bedded in the and there is a great variety of plant Bureau of Plant Industry commissioned a same place for several successive days. species available for selective graz- team of scientists to study the problem Under such circumstances everything ing. beginning with V.K. Chestnut in 1894 and near the bed ground is eaten, and if C.D. Marsh in 1905. Marsh (1913) pub- Schuster (1978) stated that good range there are any poisonous plants some of lished a short bulletin Stock poisoning Due management is the surest and most eco- the sheep are pretty sure to get them. to Scarcity of Food in which he listed the nomical means of reducing livestock loss conditions where livestock were poisoned Large catastrophic livestock losses to poisonous plants. Desirable forage

286 JOURNAL OF RANGE MANAGEMENT 55(3) May 2002 Table 2. Plant/animal/environment interactions of poisoning Colorado and southern Utah; duncecap larkspur (D. occidentale Wats.) in north Plant Animal Environmental and western Wyoming, Montana, Idaho, Ecology Species and class Plant population cycle northern Utah and Nevada; Sierra larkspur Habitat Physiological condition Toxin level (D. glaucum Wats.) in and Abundance Hunger Animal behavior Oregon and northward to Alaska; and Toxin Preference Relative palatability waxy larkspur (D. glaucescens Rydb) in southwest Montana and central Idaho. species are encouraged, while undesirable many poisonous plants, with die-offs These species differ in toxicity (Ralphs et and poisonous species are suppressed, and occurring during drought and population al. 1997), but inhabit similar ecological animals are provided abundant nutritious explosions during wet periods. Weather sites. forage. stress (drought, temperature, frost) can Ellison (1954) conducted one of the increase toxin concentration in many most comprehensive ecological studies of plants. Specific weather events can also the subalpine vegetation of the Wasatch Plant/Animal/Environment affect grazing behavior, causing animals Plateau in central Utah. Tall larkspur Interactions of Poisoning to increase consumption of specific poiso- occurred in 2 plant communities. It was a nous plants. All of these factors interact to principal component of the mixed upland In spite of the improved range condi- determine whether an animal is poisoned. herb association in its climax stage, com- tions, losses to poisonous plants continue prising 2-5% of total cover, ranging up to to occur, although not at the catastrophic 50% in some areas. Tall larkspur was also levels of the past. Dwyer (1978) stated Ecological Status of Important one of the most conspicuous species of the "We are long past the time we can pass off Poisonous Plants tall forb community on snow drift sites poisonous plants as a symptom of an over- and at the edge of wet meadows and along grazed range." Dwyer called attention to Larkspurs streams. Abusive grazing from 1880 to the need for research on plant/animal inter- Larkspurs kill more cattle on mountain 1905 practically destroyed the original actions of poisoning (Table 2). I would add and foothill rangelands than any other herbaceous vegetation, resulting in accel- to that, the environmental factors that plant or disease. Early losses ranged from erated erosion and destructive flooding in influence both plants and animals. We 3-5% of cattle grazing on larkspur infest- the valleys below. Tall larkspur was one need to consider individual plant species, ed rangelands, with over 5500 cattle of the most tenacious forbs in the original their toxin and concentration within the deaths reported annually (Aldous 1917). complex, persisting on elevated hum- plant; the plants' ecological status (Table We estimated over 1,000 cattle die annual- mocks held together by its extensive root 3), the soils and sites they occupy, their ly from larkspur in the Intermountain system. Forest Service management and population cycles, and other factors that Forest Service Region (Nielsen and reduction in livestock from 1910 to 1950 influence their relative abundance. Ralphs 1988). Losses of similar magnitude arrested the deterioration, which allowed The animal factors depend first on occur in the Rocky Mountain and secondary succession to proceed. Range whether the animal eats the toxic plant. Northern Forest Service Regions, and surveys in 1912, 1936, and 1946 docu- Many plants are highly toxic, but seldom additional losses occur on private range- mented improvement in vegetation compo- eaten [i.e. water hemlock, (Cicuta dou- lands. Larkspurs contain norditerpenoid sition. Ellison compared ungrazed relic glasii (DC.)Coult.. & Rose) narrow leaved alkaloids, which cause muscular paralysis areas to ranges grazed by either sheep or milkweeds (Asclepias spp), jimson weed and rapid death from respiratory failure. cattle. Tall larkspur declined on sheep (Datura stramonium L.)]. If the animal Sheep are more resistant to larkspur alka- range, indicating that sheep grazing eats the plant, poisoning depends on the loids than are cattle (Olsen 1978). reduced its density. Thus on sheep ranges, toxin level in the plant , and the rate of The tall larkspur complex is comprised it acts as a decreaser species. On ranges consumption. The rate of consumption of 4 species: tall larkspur (D. barbeyi grazed by cattle, its density did not change. depends on the plants relative palatability Huth.) in southcentral Wyoming, It is doubtful that further reduction in live- and its abundance in the plant community. Palatability any plant is relative to what of Table 3. Ecological status of important poisonous plants. other forage is available. Some poisonous plants are relatively more palatable than Pristine species Seral Alien the associated vegetation, i.e. larkspur Pre-European Increaser species Invader species (Delphinium spp.) and locoweeds Tall larkspur Locoweed Halogeton (Astragalus spp.), whereas the lack of bet- Western false hellebore Lupine St. Johns wort ter alternatives and hunger may drive ani- Water hemlock Death camas Poison hemlock mals to consume other poisonous plants. Bracken fern Snakeweed Tansy ragwort Some situations may cause animals to Chokecherry Threadleaf groundsel Houndstongue graze non-selectively, such as releasing Ponderosa pine Low larkspur African rue hungry animals into areas of poisonous Oak spp. Timber milkvetch Leafy spurge plants, or introducing non-native animals Bitterweed Yellow star thistle Twin leaf senna Knapweeds to areas of unfamiliar poisonous plants. White snakeroot Environmental factors affect both plants Orange sneezeweed and animals. Population cycles occur for

JOURNAL OF RANGE MANAGEMENT 55(3) May 287 stock grazing, or removal of grazing would Locoweeds reported white locoweed had a higher ger- decrease larkspur populations. Marsh(1909) stated, "The so-called mination rate on bare soils. He reasoned Sierra larkspur is described as an `locoweed disease' has been a source of that bare soils would provide greater scari- increaser species in the transition from the most serious complaint for many years, fication from soil particles for the hard fescue prairie to forest in western Canada especially from stockmen on the Great seed coat, and that higher soil tempera- (Looman 1984). Overgrazing of range and Plains east of the Rocky Mountains. While tures would enhance germination. He con- open forests in this area led to an increase the losses have varied in severity, they cluded that range deterioration caused by in its density, and significant cattle poison- have reached such a magnitude as to make heavy grazing is a factor in the increase of ing. With continued heavy grazing, it can the matter of national concern." Marsh white locoweed populations. be grazed out of the fescue grasslands. In surveyed the government files and existing Weather also influences locoweed popu- the northern boreal forests and in the tops literature and found that locoweed poison- lations. Although white locoweed appears of the Sierra and Cascade mountains, it ing was often confused with starvation. to be more persistent and longer-lived than occurs along stream banks and willow Marsh's early opinion was "An abundance Astragalus locoweeds, its populations still thickets as a minor component of the cli- of good feed would greatly reduce and cycle. Marsh (1909) observed the white max community. perhaps eliminate the problem." locoweed was particularly abundant in wet The low larkspur species form a com- White locoweed, or white pointloco years, but nearly disappeared in dry sea- plex group which introgress into each (Oxytropis sericea Nutt. ex Torr. & Gray), sons. We found that white locoweed popu- other. D. menziesii DC. was first to be is the most wide-spread locoweed species, lations in northeast New Mexico and north implicated with poisoning of sheep in ranging on the eastern foothills of the central Colorado died out in the respective Montana (Wilcox 1897). D. bicolor Nutt. Rocky mountains from Canada to New droughts in 1996 and 1997 (Ralphs, of the northwest was studied thoroughly in Mexico, and on mountain tops in the unpublished data). early toxicity studies (Chesnut and Wilcox Colorado Plateau and Great Basin. Payne Many of the semi-desert Astragalus 1901). D. nelsonii Greene occurs through- (1957) conducted a study of its' ecology locoweeds experience extreme population out Utah and Colorado. Presently, D. nut- and life history and concluded that white cycles and exhibit opportunistic survival talanium Pritz. which extends northward locoweed was found on dry sites, such as strategies that are independent of grazing into Canada, now encompass all of these rocky ridges and gravely plains. His pressures. They germinate following species, except for D. bicolor. All of these research found the overriding soil factor autumn rains, remain green over winter, species or varieties are considered increas- influencing the presence of white flower in spring, and may continue to er plants; increasing in density as grazing locoweed was the presence of coarse rock grow for 1 or 2 years until the next pressure increases and range condition fragments. Soils with greater than 15% of drought occurs, and the population dies deteriorates. Thus, improvement in range coarse fragments by volume, or very shal- back (Welsh 1989). Barnes (1913) related condition is likely to reduce their density. low soils with fractured rock beneath that the spring of 1888 was a particularly The low larkspurs grow early in the favored white locoweed. Soil texture was bad loco (probably A. lentiginosus Dougl.) spring, flower in May and June, then not definitive, since all soils where it season in northern Arizona, and that thou- senesce. They are toxic throughout their occurred were varieties of loam. He con- sands of locoed horses and cattle died. The growing period but only cause poisoning cluded that the coarse rocks allowed for previous winter was unusually wet, fol- problems when they grow in dense patch- deep percolation of water, which can be lowed by heavy rains in the early spring. es. Normally, they are scattered, but in accessed by the deep tap root of white Population outbreaks of A. lentiginosus cool wet springs when grasses are slow to locoweed, thus allowing it to survive in var. wahweapensis Welsh occurred every develop, they increase, or are more appar- droughty sites. Ralphs and Cronin (1987) 6 to 8 years in the Henry Mountain area of ent, thus causing poisoning. Since they dry also found that white locoweed preferred southeast Utah (Ralphs and Bagley 1988) up in early summer, the management rec- shallow rocky soils in north western Utah, and were strongly correlated with above- ommendation is to wait until low larkspur where it exhibits a stress tolerant survival average fall and spring precipitation. matures and other forages are abundant strategy. Population outbreaks of A. pubentissimus before turning cattle in (Pfister and Payne's (1957) second objective was to T. & G. occurred in eastern Utah in 1918, Gardner 1999). determine the influence of grazing on the 1957, 1965 (James et al. 1968), and in Plains larkspur (D. geyerii Greene) abundance of white locoweed. He 1996 (Ralphs, unpublished data), causing causes most of the poisoning problems in described 8 fence line contrasts encom- catastrophic livestock loss, yet the plants Wyoming and eastern Colorado (Alley passing the same soils, but differing range were practically nonexistent in other and Lee 1970). It is favored by cool, wet condition. Basal density index of white years. Standing crop of woolly locoweed springs, when most poisoning occurs locoweed increased as range condition (A. mollissimus Torn.) averaged 190 kg/ha before grasses start rapid growth. deteriorated from excellent to good condi- in a grazing trial at Gladstone NM in 1991 Anderson larkspur (D, andersonii Gray) tion, but decreased when condition further (Ralphs et al. 1993), but totally died out 2 generally grows as isolated plants on declined from good to fair. He concluded years later. foothill ranges throughout the Intermountain that white locoweed was a typical increas- In summary, most locoweeds are region. It only causes problems when it er species, and was positively correlated increaser species; increasing as range con- grows in dense patches on overgrazed with other increaser grasses and forbs, dition declines. Therefore, improving ranges where little other forage is available such as prairie junegrass, western wheat- range condition should reduce their densi- (Fleeting et al. 1923). grass, blue grama, needleleaf sedge, ty, though will probably not eliminate the fringed sagewort, and phlox. problem. Populations of both Oxytropis In germination trials, Payne (1957) and Astragalus locoweeds cycle with

288 JOURNAL OF RANGE MANAGEMENT 55(3) May 2002 weather. They tend to increase during wet cause acute respiratory failure, primarily reduced the incidence of acute poisoning years, and die out during drought. in sheep. The following species have been in sheep. Scattered incidents of crooked responsible for the majority of sheep loss- calf disease occur infrequently when the Milkvetch Species Containing es: L. leucophyllus Dougl. ex Lindl., L. management recommendations of Keeler Nitrotoxins leucopsis Agardh., L. argenteus Pursh, L. are ignored. About half of the Astragalus species in sericeus Pursh (Marsh and Clawson North America contain nitrotoxins. Unlike 1916). Many other species contain varying Death Camas the locoweeds, nitrotoxins cause acute levels of quinolizidine alkaloids and have Marsh and Clawson (1922) stated that poisoning in the form of respiratory fail- caused poisoning experimentally, or on "Of all the poisonous plants which cause ure, and more long-term weakness in the isolated occasions. Most of the species losses to the sheepmen of the western hind legs from demylenization of the that cause sheep poisoning are increases stock ranges, death camas (Zigadenus species. They in the spinal cord. occur native plant without a doubt, is the most trouble- communities, but increase with distur- spp.) Timber milkvetch (A. miser Dougl. ex some." There are over 15 species of death In Hook) is an important poisonous plant of bance. the past, the most widespread camas distributed throughout the western the upper rough fescue grasslands and disturbance was overgrazing. Areas states, and in many areas grow in great around watering holes, salt licks, bed lower montain areas of British Columbia abundance. They contain sterodial gly- and Alberta Canada. It also occurs in open grounds, and trail driveways often had coalkaloids which cause salavation, nau- areas of woodlands and within the moun- dense concentrations of lupine. Lupine sea and respiratory failuare. Death camas species also increase tain big sagebrush communities southward rapidly following is one of the first plants to begin growth in throughout the Rocky Mountains. fire. The combinations of dense concentra- the spring. Its early growth combined with tions MacDonald (1952) stated that overgrazing of lupine and hungry animals that early turnout of livestock resulted in poi- was undoubtedly the greatest single factor graze indiscriminately set up the condi- soning. The range management principle tions Kingsbury contributing to timber milkvetch poison- of poisoning. (1964) stat- to wait until range readiness when grass ing. It is unpalatable when adequate forage ed, "Almost all cases of loss occur under and other forage was available, greatly is available, but upon depletion of desir- circumstances which cause the animals to reduced poisoning problems. able forage, stock will consume large consume large quantities of podded lupine Although a significant problem in the a time. quantities. Later grazing studies verified over brief period of These include past, few cases of poisoning occur today. that cattle avoided eating timber milkvetch driving hungry animals quickly through Dense concentrations are seldom found. when adequate grass was available, but areas heavy with lupine, so that they have Most commonly, individual plants are consumed increasing quantities as grass little chance to be selective in their graz- scattered among sagebrush and other veg- became scarce (Quinton et al. 1989). ing; unloading or bedding down hungry etation. Furthermore, it is an apparent However in timbered areas, milkvetch was animals where lupine is the major vegeta- plant, and sheepmen know to avoid areas relatively more palatable than pinegrass tion; and trailing animals where snow has where it grows, especially if their sheep (Majak et al. 1996). Timber milkvetch covered the grasses, leaving lupines as the are hungry. poisoning remains a significant poisoning only green vegetation available." problem in southern Canada even though The second lupine syndrome is crooked range conditions have improved. calf disease (Shupe et al. 1967). This Conclusion Red-stem peavine (A. emoryanus occurs when a pregnant cow consumes Lupine species between the 40 to 70`h days (Rybd.) Cory) is a winter annual on short- Western U.S. rangelands are inherently of gestation. The teratogen stops uterine grass prairies of southern New Mexico susceptible to poisonous plant problems motility during this period, causing perma- and west . In dry years, plants are because of the wide variety of plants con- nent curvature of the spine and limbs in small and scattered. When precipitation is taining toxic compounds. Overgrazing the position the fetus is lying. The terato- timely and abundant, seeds germinate and intensified poisoning problems by causing genic alkaloid anagyrine has been found in plants grow profusely, often forming a the desirable forage species to decline, L. sulphureus, L. sericeus, L. caudatus veritable carpet on large areas of range- allowing less palatable and poisonous Kell., L. laxiflorus Dougl., L. latifolius land. A population outbreak occurred in species to increase, thereby compelling Agardh, and teratogenic piperdine alka- the winter of 1974 and spring of 1975 in livestock to consume poisonous plants loids have been found in L. formosus and the region surrounding Roswell New with resulting catastrophic losses. This has L. arbustus Dougl. ex Lindl.. The terato- Mexico. Cattle mortality averaged 2-3%, been a hard lesson to learn. Some ranchers genic alkaloids are generally higher during and morbidity averaged 15-20% are still struggling with the problem. flowering. Keeler et al. (1977) recom- (Williams et al. 1979) Schuster's (1978) solution still applies, mended that pregnant cows should not be "Good range management is the surest and given access to lupine during their 40 to most economical means of reducing live- Lupine 70 day of gestation, especially when the stock loss to poisonous plants." Lupines (Lupinus spp.) are among the teratogen level was high during flowering However, poisoning still occurs, even most conspicuous of the flowering plants on or in the seed pod stage. foothill and mountain rangelands, with over Good range management and corre- on good condition rangelands. Some poi- 100 species in the western US and Canada. sponding improved range condition has sonous plants are part of the pristine or cli- max plant community and will be abun- Because of hybridization, their is reduced dense patches of lupine, and the dant on better condition rangelands. If difficult. There are 2 toxic syndromes knowledge of the stressful conditions that caused by Lupines. Quinolizidine alkaloids cause sheep to graze it have greatly these species are palatable, like tall lark-

JOURNAL OF RANGE MANAGEMENT 55(3) May 289 spur, extensive management strategies Marsh, C.D. and A.B. Clawson. 1922. The Stoddart, L.A. and A.D. Smith. 1955. Range must be developed to avoid the conditions stock poisoning death camas. USDA Farm. Management 2nd Ed. McGraw-Hill, N.Y. Stoddard, L.A., A.H. Holmgren, and C.W. where cattle are likely to eat them (Pfister Bull. 1273. MacDonald, M.A. 1952. Timber milkvetch Cook. 1949. Important poisonous plants of et al. 1997, 1993). Abundance of other poisoning on British Columbia ranges. J. Utah. Utah Agr. Exp. Sta. Special Report 2. toxic plants will vary with the climate Range Manage. 5:16-21. Stoddart, L.A., A.D. Smith and T.W. Box. (locoweeds, milkvetch, low larkspur, Majak, W., L. Stroesser, J.H. Hall, D.A. 1975. Range Management 3rd Ed. McGraw- lupine, snakeweed). It is necessary to rec- Quinton, and H. E. Douwes.1996. Seasonal Hill, N.Y. ognize the weather conditions and climatic grazing of Columbia milkvetch by cattle on Valentine, J.F. 1990. Grazing Management. factors that favor their increase and make rangelands in British Columbia. J. Range Academic Press, N.Y. Manage. 49:223-227. Welsh, S.L.1989. Astragalus L. and Oxytropis In these cases, other grazing arrangements. Nielsen, D.B. and M.H. Ralphs 1988. DC.: definitions, distributions, and ecological aversion short-term herbicide control or Larkspur: economic considerations. pp. 119- parameters. pp. 3-13, In: L.F. James, A.D. conditioning may get a rancher through 129 In: L.F. James, M.H. Ralphs and D.B. Elbein, R.J. Molyneux, C.D. Warren (eds.), the critical periods. Nielsen (eds), The Ecology and Economic Swainsonine and Related Glycosidase Impact of Poisonous Plants on Livestock Inhibitors. Iowa State Univ. Press. Ames Production. Westview Press. Boulder Colo. Iowa.. Literature Cited Olsen, J.D. 1978. Tall larkspur poisoning in Wilcox, E.V. 1897. Larkspur poisoning of cattle and sheep. J. Amer. Vet. Med. Assoc. sheep. Mont. Agr. Exp. Sta. Bull. 22. 173:762-765. Williams, M.C., L.F. James and B.O. Bond. Aldous, A.E.1917. Eradicating tall larkspur on Payne, G.F. 1957. Ecology and life history of 1979. Emory milkvetch (Astragalus cattle ranges in the national forests. USDA the poisonous plant, white locoweed emoryanus) poisoning in chicks, sheep and Farmers Bull. 826. (Oxytropis sericea Nutt.). Ph.D Diss. Texas cattle. Amer. J. Vet. Res. 40:403-406. Alley, H.P. and G. Lee. 1970. What can be A&M Univ., College Station, Tex. done about controling larkspur on western Pfister, J.A. and D.R. Gardner. 1999. rangelands. Down to Earth 26:31-32. Consumption of low larkspur (Delphinium Barnes, W.C. 1913. Western grazing grounds nuttallianum) by cattle. J. Range Manage. and forest ranges. The Breeder's Gazette, 52:378-383. Chicago. 390 pp. Pfister, J.A., D.R. Gardner and K.W. Price. Box, T.W. and J.C. Malechek.1987. Grazing 1997. Grazing risk on tall larkspur-infested on the American rangelands. Proc. West. ranges. Rangelands 19:12-15. Sec. Anim. Sci. 38:107-115. Pfister, J.A., M.H. Ralphs, G.D. Manners, Chesnut, V.K. and E.V. Wilcox. 1901. The K.E. Panter, L.F. James, B.L. Stegelmeier, sotck-poisoning plants of Montana. USDA and D.R. Gardner. 1993. Tall larkspur poi- Bot. Bull. 26. soning in cattle: current research and recom- Dwyer, D.D. 1978. Impact of poisonous plants mendations. Rangelands 15:157-160. on western U.S. grazing systems and live- Quinton, D.A., W. Majak, and J.W. Hall. stock operations. pp. 13-21, In: R.F. Keeler, 1989. The effect of cattle grazing on the K.R. VanKampen, and L.F. James (eds), growth and miserotoxin content of Columbia Effects of Poisonous Plants on Livestock. milkvetch. J. Range Manage. 42:368-371. Academic Press. N.Y. Ralphs, M.H. and V.L. Bagley. 1988. Ellison, L. 1954. Subalpine vegetation of the Population cycles of Wahweap milkvetch on Wasatch plateau, Utah. Ecol. Mono. 24:80- the Henry Mountains and seed reserve in the 184. soil. Great Basin Natur. 48:541-547. Fleming, C.E., M.R. Miller, and L.R. Ralphs, M.H. and E.H. Cronin. 1987. 1923. The low larkspur (Delp-hini- Vawter. Locoweed seed in soil: density, longevity, ger- um andersoni). Univ. Nev. Agr. Exp. Sta. mination and viability. Weed Sci. Bull. 105. 35:792-795. Looman, J. 1984. The biological flora of Ralphs, M.H., D.Graham, R.J. Molyneux, Canada: 5. Delphinium glaucum Watson, tall and L.F. James. 1993. Seasonal grazing of larkspur. Canada Field-Nauural. 98:345-361. locoweeds by cattle in northeastern New James, L.F., K.L. Bennett, K.G. Parker, R.F. Mexico. J. Range Manage. 46:416-420. Keeler, W. Binns, and B. Lindsay. 1968. Ralphs, M.H., G.D. Manners, J.A. Pfister, plant poisoning in sheep. J. Range Loco D.R. and L.F. James. 1997. Manage. 21:360-365. Gardner, in larkspur Keeler, R.F., L.F. James, J.L. Shupe, and Toxic alkaloid concentration tall species in the western U.S. J. Range Manage. K.R. VanKampen. 1977. Lupine-induced 50:497-502. crooked calf disease and a management plant manage- method to reduce incidence. J. Range Schuster, J.L. 1978. Poisonous measures on U.S. Manage. 30:97-102. ment problems and control In: R.F. Keeler, K.R. Kingsbury, J.M. 1964. Poisonous plants of the rangelands. pp. 23-34, United States and Canada. Prentice Hall, VanKampen, and L.F. James (eds), Effects of Englewood Cliffs, N.J. Poisonous Plants on Livestock. Academic Marsh, C.D. 1909. The locoweed disease of Press. N.Y. the plains. USDA Anim. Ind. Bull. 112. Shupe, J.L., W. Binns, L.F. James, R.F. Marsh, C.D. 1913. Stock poisoning due to Keeler. 1967. Luupine a cause of crooked scarcity of food. USDA Farm. Bull. 536. calf disease. J. Amer. Vet. Med. Assoc. Marsh, C.D. and A.B. Clawson. 1916. 151:198-203. Stoddart, L.A. and A.D. Smith. 1943. Range Lupines as poisonous plants. USDA ls` Bu11.405. Management Ed. McGraw-Hill, N.Y.

290 JOURNAL OF RANGE MANAGEMENT 55(3) May 2002