UC-NRLF 33fl DEATH CAMSS Plants Poisonous to Sheep and Battle By C.S. Fleming & ff.F. Peterson Univ. of Nevada Bulletin #101 - Feb. 19E1 : ' Kore&try. JMaio L.ibra.r THE UNIVERSITY QF NEVADA AGRICULTURAL EXPERIMENT STATION Bulletin No. 101 RENO, NEVADA February, 1921 To diminish suffering and loss among domestic animals DEATH CAMAS (Zygadenus paniculatus and Zygadenus venenosus) Plants Poisonous to Sheep and Cattle By C. E. FLEMING and N. F. PETERSON Of the Department of Range Management Assisted by M. R. MILLER Of the Department of Chemistry and DR. L. H. WRIGHT Of the Department of Veterinary Science PUBLISHED BY THE UNIVERSITY OF NEVADA RENO, NEVADA I 55 Printed at the STATE PRINTING OFFICE JOE FARNSWORTH, SUPERINTENDENT CARSON CITY, NEVADA NEVADA AGRICULTURAL EXPERIMENT STATION BOAED OF CONTROL Hon. G.F.TALBOT (1931) . . . Reno Hon.B. F. CUBLEB (1921) Elko Hon. WALTEB E. PRATT (1925) Reno Hon. Mrs. W. H. HOOD (1927) Reno Hon. MILES E.NOBTH (1929) Reno OFFICERS WALTER E. CLARK, Ph.D President of University CABOLYN BECKWITH Secretary CHABLES H. GORMAN Comptroller STAFF SAMUEL B. DOTEN, M.A Director and Entomologist F. L. BIXBY, C.E Irrigation (In cooperation with Bureau of Public Roads, U. S. D. A.) GEO. HABDMAN, M.S. ....... Assistant in Irrigation CHABLES E. FLEMING, B.S.A Range Management EDWARD RECORDS,V.M.D. . Veterinarian LYMAN R.VAWTEB, D.V.M Pathologist MADGE L. FINK, B.A Secretary to Veterinary Department M. R. MILLER, B.S Chemist MABTHA RYAN Librarian and Secretary to Director ^ STUDIES OF POISONOUS RANGE PLANTS IN THE UNIVERSITY OF NEVADA In undertaking the study of poisonous range plants, the Nevada Agricultural Experiment Station has planned a series of experiments to obtain information upon the following points : ( 1 ) the part of the plant which is poisonous, (2) the time of the year when it is dangerous, (3) the kinds of live stock poisoned, (4) the amount which must be eaten in order to cause illness or death, (5) the symptoms shown by the poisoned animals, (6) the conditions under which poisoning occurs, (7) methods of cure and treatment, (8) and methods of preventing poisoning. In addition, studies are made of the post-mortem conditions shown by the poisoned animal, and of the chemical nature of the poisonous element found in the plant. The basis of all these experiments consists of long series of feeding tests in which plants are brought fresh from the ranges to the Univer- sity and are fed to range animals in pens where they are kept under close observation. This bulletin is a report of the results obtained by feeding the plant known as death camas to range sheep and cattle. S. B. DOTEN, Director, Nevada Agricultural Experiment Station. UNIVERSITY OF NEVADA, Reno, Nevada, January, 1921. 48130, SECTION I DEATH CAMAS Zygademis paniculatus and Zygadenus venenosus PLANTS POISONOUS TO SHEEP AND CATTLE SUMMARY Death camas is a common poisonous plant of the sheep and cattle ranges in Nevada. It is a low-growing bright-green plant related to the lilies and the onions. It comes up in the very early spring from a bulb buried eight inches or more in the ground. The bulb is much like an onion, but it has no onion odor, and is covered with a thin black coating. The leaves are long, slender, and grass-like. When the plants come up they look a little like Indian corn ; but the leaf is narrower and more fleshy, and it has a distinct ridge or keel on the under side. At first there appears to be no stem ; but later a flower stalk is sent up bearing a long cluster of pale yellow flowers. The first green shoots come up early in the spring before there is grass on the range ; and it is at this season that sheep and some cattle are poisoned. It takes from one-fourth to one-half pound of the leaves to make a range sheep sick when the animal is confined in a pen ; it takes a much larger dose, three pounds or more, to kill a sheep under the same condi- tions. On the range where sheep are driven hard and have no chance to rest and recover, smaller doses are probably often fatal. On the whole, however, under ordinary range conditions it must be somewhat difficult for even one sheep in a band to obtain a fatal dose of the death camas leaves; and it is probable that many losses thought to have been caused by death camas were in reality caused by some other plant. Sheep fatally poisoned by death camas froth at the mouth and slobber freely, and occasionally vomit. They grow weak in the hind- legs and stagger when made to walk. Within a few hours they become very dull and weak, standing with head and ears drooping and the back arched. Later, they go down and thereafter rise with difficulty if at all ; becoming gradually weaker and usually dying within twenty- four hours from the time of feeding. Cattle show much the same set of symptoms; but are apt not to froth at the mouth and drool as much as sheep. When in good condi- tion they vomit so freely that they recover within two or three days. In our experiments we did not succeed in killing any young cattle with death camas. Doses of three-eighths of a pound to two pounds made the animal sick, but caused prompt and profuse vomiting which brought about a fairly rapid recovery. On the range, death probably occurs only when half -starved cattle eat a considerable quantity under conditions where the system is too weak to throw off the poison or where weak animals, driven hard, are poisoned and get no chance to rest and recpyer. There is no known remedy for death camas poisoning; and even if an antidote were discovered, it is not likely that it could be used sue- r-r-- Figure 1. Toot-Hill Death Camas, the Entire Plant, in Bloom. cessfully under range conditions. Since poisoning occurs only when weak and hungry animals are turned on to death camas ranges where there is no grass or other green feed, and since ordinarily both sheep and cattle will avoid death camas and eat almost anything else in pref- erence, it is evident that the way to avoid poisoning is to keep half- starved animals off death camas ranges and feed some hay until there is grass ; and then let the animals scatter out and browse at will, choosing their own forage. The plants known as death camas have long been recognized as poisonous, being commonly considered as among the most dangerous plants of our western sheep and cattle ranges. Although discussed in nearly all publications dealing with poisonous plants, there is little if any definite information concerning the quantity required to make an animal sick or to cause death; and not much appears to be known about the classes of live stock poisoned, the conditions under which poisoning is most likely to occur, and methods of preventing losses. The experimental feedings and range observations presented in this bulletin were made for the purpose of obtaining exact information upon these points. Classes of Live Stock Poisoned. All of the range observations seem to show that more sheep than cattle or horses are poisoned by death camas. No losses of horses have been recorded by the Nevada Experiment Station; and it seems that cattle have been poisoned only when hungry and in poor condition in the spring of the year. Many of the losses on the open range which have been attributed to death camas may in reality have been caused by other plants not known at the time to be poisonous. In fact, a large number of range observations made by the Station show that the probability of poisoning by this plant is by no means so great as is commonly supposed. This side of the matter will be discussed at length farther on in this bulletin. Common Names. Death camas is the name by which these plants are commonly known on the range; but they are also called Mystery Grass, Poison Sego, Poison Onion, Lobelia, and Poison Camas. In Nevada the most common kinds are the foot-hill death camas (Zygadenus paniculatus) , and the meadow death camas (Zygadenus venenosus). The former grows in the foot-hills among sagebrush and other range browse ; the latter is more plentiful ,in moist, grassy places. The foot-hill form is more common in Nevada, being found on most of the ranges in the northern part of the State. A Description of Death Camas. The group of closely-related plants known as death camas were formerly included in the lily family ; but this family has recently been broken up by botanists who have placed the death camas in the "bunch-flower family" (Melanthacece) . The plant is erect, producing from two to eight fully formed grass- like leaves. It springs from a layered bulb set from two to eight inches deep in the soil. The bulbs vary in size according to the age of the plant ; but they are commonly from one-half to one and one-fourth inches across and are covered by thin, black, papery coats or layers. The leaves are long, narrow, and curved; varying in length from six 8 to eighteen inches; they they look a good deal like Figure 2. Foot-hill Death Camas, the Young Plant in Early Spring. are usually less than one-half inch wide; coarse grass blades with a projecting ridge like the keel of a boat on the under side. They are much thicker and more juicy than ordinary grass blades. There is at first no well-defined stem, the leaves appearing to rise from near the surface of the ground. The flowers are greenish - yellow or whitish, about one- fourth inch across ; and are produced in a flower cluster from two to ten inches long. The lower flowers bloom first, and may pro- duce seed pods before the upper flowers bloom. The seeds ripen in the summer; but lie dormant until the next spring, when they sprout and grow into tiny leafy plants. These soon develop small bulbs which may not be any larger than a pea by the end of their first summer's growth. It takes a new plant several seasons to form a bulb sufficiently large to begin to produce flowers and seeds. The foot-hill death camas differs from the meadow form by having a larger and longer bulb, lying deeper in the soil, usually at a depth of from five to eight inches ; while the bulb of the meadow form is smaller and much shorter and is rarely found more than two inches deep in the ground. The foot-hill death camas is also a much larger plant; its flower cluster is branched at the base, while the much shorter cluster of the meadow form is unbranched. Plants Commonly Mistaken for Death Camas. Death camas is most commonly confused with the wild onion, although it has no onion odor. When in bloom the two are easily distinguished, for all of the flowers of the onion cluster grow out from the tip of the flower stem, while the flowers of the death camas grow along the sides of the stem as in Figure 4. Where the Death Camas Grows. Death camas plants may be found on practically every stock range in Nevada, growing more abundantly in the northern half of the State than in the southern. The ground on which the death camas grows is always quite moist in the spring of the year; and the typical grazing types in which they are found are: (1) sagebrush, (2) grass, (3) semimeadow areas, and (4) typical weed ranges where the vegetation consists largely of showy flowering plants. They do not grow in the shade under standing timber. They are found on practically all of the mountain foot-hills, the high open mountain park areas, and in the sagebrush country of northern and western Nevada. The Time of Year When Growth Begins. The time when death camas starts to grow in the spring varies with the season and also with different exposures and different soils; the green shoots are sometimes found as early as the middle of March. Figure 3. Foot-Hill Death Camas. Plants in various stages of growth, from seedlings to mature plant in bloom. The plants make their appearance first on sandy soils and on southern exposures. On the dark loamy and clay soils their growth is much retarded; probably because these soils are moist and consequently warm up less readily. If the weather is fairly warm the death camas will begin to grow from ten days to two weeks after the snow melts out in the spring; and the leaves are soon high enough to cause loss. By the latter part of June on the lower ranges, the plant has usually died down. How the Flavor of Death Camas Affects the Probability of Poisoning. All species of death camas which grow in Nevada have a bitter flavor and are extremely distasteful to cattle and sheep. In all our feeding 10 tests it was practically impossible to get either sheep or cattle to eat this plant readily, even after going hungry for two or three days. When a hungry animal was first fed, a few mouthfuls would be eaten ; but almost as soon as the plant juices came in contact with the mouth the animal would begin to wrinkle its nose and move its tongue in such a manner as quickly to get rid of what was in its mouth. In order to get any large number of plants into an animal it was necessary to resort to forced feedings, which consisted mainly in plac- ing the ground leaves so far back in the animal's mouth that it had to swallow what was given it. When this plant, mixed with palatable Figure 4. Foot-Hill Death Camas (on left) and Wild Onion. Notice the differ- ence in the arrangement of the flowers on the stem. The flowers of death camas are scattered along the sides of the stem; those of wild onion form a round cluster at the end of the stem. weeds and grasses, was fed to hungry animals they would sort out the grasses and weeds and eat them, avoiding the death camas wherever possible. This shows clearly how sheep and cattle dislike this poisonous plant and try to avoid eating it. On many of the grazing ranges in the western part of Nevada, sheep have been closely observed while grazing on ground supporting death camas, with weeds, browse, and a scattering stand of grasses. The sheep nibbled weeds and grasses all around the death camas, leaving it almost untouched. Naturally, no losses occurred under these conditions. 11 On several of these ranges it was noticed that the death camas plants had been grazed by some animal. A study of conditions on near-by ranges, where it was known that there had been no live stock that season, revealed the fact that a number of rodents, common ground squirrels among others, were eating the leaves and digging up the bulbs. Ordinarily, if there had been sheep on these ranges and poison- ing had occurred, it would have been seen that the death camas plants had been grazed ; and they would have been blamed for the losses. A series of similar observations were made on Peavine Mountain, near Reno by J. A. Longyear who states that the tops of death camas plants are nibbled rather freely by ground squirrels. Because of the fact that in the experimental work it took a large quantity of death camas to kill a sheep, a series of feeding tests were made with the most palatable young green weeds and grasses to find out the amount of such plants a range sheep will eat before its hunger is satisfied. Two yearling lambs in medium condition were fed a mixture of green Figure 5. Foot-Hill Death Camas. Plants beginning growth in early spring. Figure 6. The Foot- Hill Death Camas. This plant has been nibbled by ground squirrels. grasses and weeds. These animals were fed during a series of days all they would eat in the forenoon and afternoon. The average consump- tion of weeds and grass was four and one-half pounds on each half- day, or nine pounds per day. Two old ewes weighing 80 and 90 pounds respectively were put to the same test as the lambs ; and it was found that on the average each would eat a little over eight pounds daily. These tests probably show quite accurately the quantity of green feed eaten by a range sheep in a single day. With death camas the experimental feeding tests showed that the smallest amount which will make a sheep sick is between one-fourth pound and one pound. Amounts of one-fourth to two and one-half pounds in each feeding made the sheep sick ; but none died from the direct effects of the poisoning. However, two were so weakened that they died later; one from inflammation and ulceration of the fourth 12 stomach, the other from pneumonia. Quantities of three pounds or more killed the animals in all cases, with the exception of a single sheep which appeared far more resistant to poisoning than the average animal. When we compare the capacity of a sheep 's stomach, approximately four and one-half of green grass and weeds at a single feeding, with the quantity of death camas required to kill, approximately three pounds or more ; then it would appear that the sheep would have to graze very largely on death camas in order to secure a fatal dose. In order to get a clear idea of how thick a stand of death camas there is on the range early in the spring when the danger is greatest, square- rod plots were laid out where death camas (Zygadenus paniculatus] appeared most abundant on the foot-hills southwest of Reno. On April 12, 1918, 32 plants, all that grew on one square rod, were cut off at a height of three-quarters inch above the ground. The total weight Figure 7. Foot-Hill Death Camas. The leaves appear to spring directly from the ground without any stem. was 32.8 grams, or a little more than an ounce. On April 15, 52 plants were cut from two square rods and the total weight of leaves cut was 28.6 grams per square rod, or approximately one ounce. At this rate it would take sixteen square rods to produce a single pound of the plant. The leaves at this time were from four to eight inches high. On all of these plots there was a far heavier stand of death camas than would ordinarily be found on any of the ranges in Nevada. If the plants really grew as thickly on the range as on these selected plots, and if they had reached a height of from four to eight inches, then each acre would produce from 10 to 12 pounds of death camas, enough to poison fatally some three or four sheep. The death camas was cut and weighed at a time of year when all other green vegetation was very scarce, and the likelihood of poisoning was greatest. On May 17, 1918, when other range vegetation was quite abundant, 13 17 death camas plants, all that grew on a square rod, were clipped three-fourths of an inch from the surface of the ground ; they weighed 4.8 ounces, somewhat more than one-fourth pound. The plants were then in full bloom, some of them going to seed. At this rate and at this time of year an acre would produce approximately 48 pounds of death camas, enough to poison fatally about 16 head of sheep. However, the plant does not grow as thickly as this uniformly over any sheep range. The square-rod plots were selected areas, chosen because they supported an unusual number of plants. Foot-Hill Death Camas (Zygadenus paniculatus) Feeding Experiments with Sheep. In the course of the years 1918 and 1919, 69 feedings were made to sheep. Most of these feedings were of leaves, only a few feedings being made of the flower-heads, seed-heads, and bulbs. The results of these feedings are condensed in Table I. The results of the experiments presented in this table may be summarized as follows : (1) None of the nine feedings of -J pound each had any appreciable effect upon the animal, indicating that this quantity of the plant is practically harmless ; (2) out of the 16 feedings of J pound of the tops, six tests produced no visible symptoms, while 10 made the animals appreciably sick. These feedings show that if sheep in a range flock eat as little death camas as \ pound each, trouble may possibly follow. A single feeding of \ pound of the bulbs made one sheep sick, but in a few hours it had completely recovered. It takes several plants to make \ pound of the bulbs, more plants in fact than a sheep could possibly ever pull up ; so the bulbs as. a poisonous part of the plant may be completely disregarded. (3) Nine out of 12 feedings of \ pound of the tops produced typical symptoms of poisoning, while three apparently had little effect upon the animals. A half-pound of the tops will generally make a sheep sick ; any larger quantity will almost always cause severe poisoning. (4) Four out of five feedings of f pound each made the animals sick. These sheep were much more seriously affected than those fed \ pound each. (5) Of seven feedings of one pound each, six caused severe poisoning while one had no effect. Apparently one pound is as much as any sheep can eat without danger of serious poisoning. (6) Four feedings of from \\ to 1J pounds all caused severe but not fatal poisoning. (7) Five feedings of quantities varying between If pounds and 2 pounds caused very severe poisoning, resulting in death in two cases. (8) All feedings of three pounds each resulted fatally. However, sheep No. 18 was twice fed 3^ pounds without a fatal result, although the animal was severely poisoned and was sick for more than a day each time. This animal appeared to be very resistant to poisoning by death camas ; later, in tests with other plants, she showed the same resistance to poisoning. (9) Three feedings of four pounds of the tops all caused death. It seems fair to assume that under ordinary conditions no sheep can eat such a quantity of death camas and live. Still, four pounds is a far greater quantity than any sheep is likely ever to find on the range. (10) Of three feedings of quantities of seed-heads varying between 14 TABLE I FOOT-HILL DEATH CAMAS (Z. paniculatus) . THE FRESH GREEN PLANT FED TO SHEEP. Animal No. w jgj ht Date fed Time fed Amount fed, Ibs. Time symptoms appeared Time of death or recovery Final result 13 69 72 65 67 64 70 56 81 79 93 90 96 83 71 61 82 93 93 93 93 116 75 72 73 83 77 72 56 56 53 72 120 75 75 69 68 70 66 66 75 64 64 82 94 63 70 80 75 67 68 73 72 70 65 68 75 83 77 94 94 73 83 96 67 65 12 93 88 81 5-22-18 5-22-18 5-22-18 5-22-18 6- 4-18 6- 4-18 6- 4-18 5- 6-18 5- 6-18 5- 9-18 5-10-18 5-10-18 5-14-18 5-22-18 5-22-18 5-22-18 5-22-18 5-24-18 5-25-18 6- 4-18 6- 4-18 4-17-19 5- 6-18 5- 6-18 5- 9-18 5-14-18 5-15-18 5-22-18 5-24-18 5-25-18 5-25-18 6- 4-18 4-17-19 4-23-19 5- 5-19 5- 7-18 5-22-18 5-23-18 5-24-18 4-18-19 5-24-18 5-25-18 5- 9-18 5-10-18 5-22-18 4-22-19 4-23-19 5- 9-18 5-14-18 5- 9-18 5-10-18 5-10-18 5-14-18 5-24-18 5-16-18 5-22-18 5-15-18 5-22-18 5-18-18 5-24-18 5-17-18 5-17-18 5-22-18 5- 6-18 6- 4-18 6- 4-18 5-27-18 5-15-19 5- 5-19 2:15 p. m. 2:20 p. m. 2:25 p. m. 2:30 p. m. 2:15 p.m. 2:25 p. m. 2:30 p. m. 11:10 a. m. 11:30 a.m. 10:20 a. m. 9:30 a. m. 9:40 a. m. 11:10 a. m. 2:35 p.m. 2:40 p. m. 2:50 p. m. 2:55 p. m. 9:10 a. m. 10:20 a. m. 2:35 p. m. 2:40 p. m. 11:45 a. m. 11:00 a. m. 2:40 p. m. 11:45 a. m. 11:20 a. m. 10:40 a. m. 3:15 p.m. 9:20 a. m. 10:30 a. m. 10:40 a. m. 2:50 p. m. 11:45 a. m. 11:00 a. m. 10:00 a. m. 11:30 a. m. 3:40 p.m. 10:35 a. m. 9:25 a. m. 9:30 a. m. 9:30 a. m. 10:40 a. m. 11:35 a. m. 11:05 a. m. 3:50 p.m. 10:00 a. m. 10:30 a. m. 11:50 a. m. 10:40 a. m. 10:40 a. m. 11:35 a. m. 10:35 a. m. 10:15 a. m. 9:40 a. m. 10:15 a. m. 10:15 a. m. 10:00 a. m. 11:20 a. m. 10:35 a. m. 10:25 a. m. 10:15 a. m. 10:30 a. m. 10:40 a. m. 2:55 p. m. 2:19 p. m. 2:20 p. m. 10:30 a. m. 9:40 a. m. 9:50 a. m. j : : 1 1 1 2 2 2 2 3 3 3 3 4 4 4 ; : S ! t i ' Negative 8 Negative 6 Negative 24 Negative 28 Negative 27 Negative 26 Negative 25. 2:55 p.m. 3:30 p.m. 2:30 p. m. 3:30 p. m. 5:00 p. m. 5:00 p. m. 5:00 p. m. 4:30 p. m. Recovery Recovery Recovery Recovery Negative 23--. 25 25 21 9 Negative 7 17 7:00 p. m. 8:00 p. m. 3:55 p. m. 3:55 p. m. 5-2310:00 a. m. 5-23 3:00 p. m. 5-2310:00 a. m. 7:00 p. m. Recovery Recovery 10 Recovery Recovery 25 25 Negative 25 12:00 m. 3:50 p. m. 3:00 p. m. 7:45 p. m. Recovery Recoverv 25 14 Negative 26 Negative 8 Negative 20 Negative 9 6:40 p. m. 2:30 p.m. 1:00 p.m. 4:55 p. m. 10:50 a. m. 2:40 p. m. 1:40 p.m. 4:50 p.m. 5-10 8:00 a. m. 5:00 p. m. 5:00 p. m. 10:00 p. m. 11:50 a. m. 8:00 p. m. 3:00 p.m. 7:45 p. m. Recovery Recovery Recovery -._ Recovery Recovery Recovery Recovery 5 8 26 26 26 16 2... Recovery Negative 29 26 Negative 46 - 4:45 p. m. 7:00 p. m. Recovery Negative 11 27 7:00 p.m. 1:40 p. m. 2:15 p.m. 1:30 p. m. 2:15 p.m. 12:00 m. 1:20 p.m. 3:30 p. m. 7:00 p. m. 2:40 p. m. 5-23 8:00 a. m. 8:00 p. m. 4:15 p. m. 5:00 p. m. 4:05 p. m. 8:00 p. m. 9-11 8:00 a. m. 5:00 p. m. 5-23 8:00 a. m. 4-23 8:00 a. m. Recovery Recovery 27 27 Recovery Recovery Recovery Recovery Recovery Recovery Recovery 29 28. __ 28 10... 18 28 46 Recovery Negative 29 12 2:30 p. m. 3:30 p. m. 1:20 p.m. 3:15 p.m. 2:30 p. m. 2:30 p. m. 11:05 a. m. 2:30 p.m. 12:30 p. m. 1:00 p. m. 12:30 p. m. 1:00 p. m. 10:00 a. m. 11:20 a. m. 11:20 a. m. 12:20 p. m. 11:00 p.m. 4:30 p. m. 5:00 p. m. 6:40 p. m. 5:15 p. m. 5-11 8:00 a.m. 5-15 8:00 a. m. 2:00 p.m. 5-18 8:00 a. m. 5-2611:00 a. m. 5-18 9:00 a. m. 5-23 1:00 a. m. 5-19 8:00 a. m. 5-25 2:00 p. m. 5-18 1:00 p.m. 5-18 8:00 a. m. 1:25 p. m. 5- 7 6:00 p. m. Recovery Recovery Recovery Recovery Death 24 19 20 . 3 16 ... Recovery Recovery 29 19 12 22. _. 5 18 18 20 9 21 24 29 8 25 29 26 Recovery Death Death Death Recovery Recovery- Death Death Death 'Recovery t Negative tNegative 11:30 a. m. 5-~2~8~ sVob a. m. tRecovery tNegative 4:45 p.m. 7:00 p.m. _-. ^Recovery *Flower heads fed. tSeed heads fed. JBulbs fed. 15 J and Vio of a pound, one caused sickness and two were without result. Apparently the green seed-heads are about as poisonous as the leaves and stems. The number of tests, however, was not great enough to prove this conclusively. As a cause of poisoning in range sheep it is believed that the seed-heads of death camas are of very little importance. Symptoms of Poisoning in Sheep by Foot-Hill Death Camas. Small doses, from J to f of a pound, cause salivation or slobbering in nearly every case. A few cases show nausea and vomiting; there is often a marked increase in the rate of respiration sometimes amounting to panting. The breathing is very irregular; for a time it' is rapid, then very slow. In some cases there is a muscular weakness, which is most noticeable in the hind-legs. With larger doses, from one to two pounds, there is in addition to the above symptoms a period of dullness during which the animal stands with the back arched and the head and ears drooping. With still larger doses the animal becomes so weak as to be unable to rise. In some cases the mucous membrane of mouth and tongue appeared blue ; and two sheep showed such a spasmodic twitching of the muscles as occurs in strychnine poisoning. Time Necessary for Symptoms of Poisoning to Appear. The time which elapsed from the time of feeding until symptoms appeared varied from one to seven hours, the average being three hours and ten minutes. The time was slightly less for the larger doses. With doses of less than two pounds the time averaged three hours, twenty-two minutes ; with doses of three pounds or more the average was two hours, twenty-five minutes. Length of Time the Poisoned Sheep Were Sick. The length of time through which the sheep remained sick was quite variable. After doses of J pound to two pounds the animals were sick for from one to eighteen hours, averaging about five or six hours. As several of these sheep recovered during the night, we do not know exactly how long they were sick. Most of the sheep which died from the direct effects of death camas poisoning were sick from twenty to twenty-five hours; and one was down and unable to rise for nearly three days before it died. Some Typical Cases of Death Camas Poisoning in Sheep. Case 1. A yearling wether weighing 81 pounds was fed J pound of the leaves of death camas at 11 : 10 a. m. May 5, 1918. At 2 : 55 p. m. it began to froth at the mouth and made attempts to vomit. The breath- ing was very irregular, alternately rapid and slow. At 4 : 30 p. m. the animal seemed to be getting better and by 5 p. m. it appeared to have recovered completely. Case 2. About one month later, on June 4, 1918, the same sheep, now weighing 93 pounds, was fed J pound at 2 : 35 p. m. At 3 : 50 p. m. it began slobbering; and at 4:05 p. m. it was nauseated and began to vomit. The breathing was at first fast' and shallow, then slow and full,, with occasional slight pauses. By 4 : 30 it had vomited an amount esti- mated at f of a quart. Vomiting ceased soon afterward and by 4 : 50 the sheep was much better. When next observed, at 7 :45 p. m., it was eating hay and appeared to have fully recovered. 16 Case 3. A yearling wether weighing 56 pounds was fed pound of death camas leaves at 3 : 15 p. m. May 22, 1918. At 4 : 35 it was froth- ing at the mouth and trying to vomit. At 4 : 40 it was vomiting freely. At 7 p. m. it was still frothing at' the mouth, but had ceased vomiting and was getting better. At 8 p. m. it seemed to have recovered. At 10 p. m. it was again slobbering a little. Next morning at 8 o'clock it had fully recovered. Case 4. A yearling wether fed f pound of the leaves at 9 : 25 a. m. May 24, 1918, began slobbering a little at 2 : 15 p. m. This gradu- ally increased, and at 3 : 20 it was foaming freely at the mouth. At 4 p. m. it was still slobbering a little ; but at 4 : 15 it began eating grass and seemed to have recovered fully. No other sj^mptoms were noted. Case 5. A ewe weighing 75 pounds was fed 1J pounds of death camas at 11:50 a. m. At 2:30 this sheep was grinding its teeth and slobbering freely. At 3 : 40 it was dull and stood with the head and ears drooping, still frothing freely at the mouth. At 4 : 30 the animal appeared to have nearly recovered, and was nibbling at feed. Case 6. A ewe weighing 68 pounds was fed 1J pounds of death camas at 10: 40 a. m. May 9, 1918. It began to froth at the mouth at 1:20 p. m. At about 1:30 it vomited a considerable amount. At 2 : 30 it was slobbering freely, and Figure 8. Death Camas Poisoning. stood with drooping head ; showing a decided weakness in the hind legs. At 3 : 30 it was salivating less freely, but still stood with head drooping. At 4 : 30 it was getting better ; but was still slobbering a little, and refused to eat. At 6 : 40 it appeared to have fully recovered. Case 7. A ewe weighing 83 pounds was fed three pounds of death camas leaves on May 15, 1918, at 10 a. m. At 1 : 30 p. m. it was slob- bering freely, was weak, and staggered when made to move. The breathing was labored, and at times the animal vomited. These symp- toms continued, the animal growing worse until 3 p. m. and becoming weak enough by 4 p. m. to stagger when walking ; it was then so weak 17 that it could easily be pushed over. The mucous membranes of the mouth and tongue were bluish. At 7 : 30 p. m. it seemed better, and did not appear so weak. At 9 a. m. next day it was down flat on the side and unable to rise. At 11 a. m. it had twitching movements of the muscles similar to those in strychnine poisoning. The animal remained down all that day. Next morning it was still down and appeared to be getting weaker; the breathing was labored and was accompanied by peculiar grunts. At 9 a. m. on the 18th it was found dead, but still warm. Case 8. A ewe weighing 77 pounds was fed three pounds of death camas at 11 : 20 a. m. May 22, 1918. At 12 : 30 it was frothing at the mouth ; by 1 : 30 it was frothing freely at the mouth and vomiting ; these symptoms continued until about 2 : 30. By 2 : 50 the animal was weak in the hind legs and staggered when made to walk. The animal continued to get worse, and by 4 p. m. was very weak and dull, standing with head and ears drooping and the back arched. At 4 :30 it vomited again. At 7 a. m. the animal was very dull, and staggered when made to move. It continued to grow worse until 10 p. m. Next' morning, at 8 a. m. it was very weak and unable to get up. It remained in this condition all the forenoon ; and died quietly at 1 : 30 p. m. Meadow Death Camas (Zygadenus venenosus) Feeding Experiments with Sheep. Only three feeding tests were made, as the plant is not at all abun- dant on the ranges in western Nevada ; and material for the tests was necessarily limited. It is much less important on Nevada ranges than the foot-hill death camas. The results of the three feedings are sum- marized in Table II. TABLE II MEADOW DEATH CAMAS (Z. venenosus}. THE GREEN LEAVES AND FLOWERS FED TO SHEEP. Animal No. Weight Ibs. Date fed Time fed Amount fed, Ibs. Time symptoms appeared Time of death or recovery Final result 37 90 6- 9-19 9:45 a. m. \ Negative 37 62 93 101 6-11-19 6-26-19 10:50 a. m. 11:00 a. m. 1 2 1:40 p. m. 11:50 a. m. 5:00 p. m. After 11:00 p. m. Recovery Death The experiments summarized in Table II show that this plant is poisonous and that amounts of one pound or more will cause serious poisoning in sheep. The symptoms produced by this plant are almost identical with those described for the foot-hill species, as will be seen from the following typical cases : Typical Cases of Poisoning in Sheep, Meadow Death Camas. Case 1. A ewe weighing 93 pounds was fed one pound at 10 : 50 a. m. At 1 : 40 p. m. it was foaming at the mouth. At 2 : 40 it was chewing cud, but still foaming at the mouth. At 5 p. m. it appeared to have recovered. Case 2. On June 26, 1919, a ewe weighing 101 pounds was fed two pounds of the plant at 11 a. m. At 11 : 50 it was foaming at the mouth and vomiting. At 1 p. m. the respiration was rapid and irregular, varying from 55 to 70 per minute. It still frothed freely at the mouth, the froth being scattered all over the pen. By 4 : 15 it was very weak, staggered when walking, trying to vomit. The animal then appeared 18 o ! I i i 0> > I* I s j a - - i 1 CQ : | 1 If i ! ! i W V^ ; 00 -N.^ , i i ; ; ; ll ; i ! ' : : ^coco. coca^ 1 1 " 1 l-H i-H *- *~ j ^ o 1 - I ^" H ! i | ~*