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GENUS: Dicentra

Dicentra Cucullaria (L ) Bernh.—Dutchman's breeches

Dicentra canadensis (Goldie) Walp.—Squirrel-corn

Dicentra eximia (Ker) Torr. - Bleeding heart

FAMILY: Fumariaceae—the Fumitory Family

Flowers are perfect, 2-nerved, bilaterally symmetrical; sepals: 2, falling early from the flower; petals: 4, 2 outer and 2 inner; outer 2 petals fused at base, free at the ends, one or both forming basal sacs; inner 2 petals slender at base, fused over the stigma at apex; stamens: 6; leaves: glabrous, herbaceous decompound or dissected; stems: watery, juice apparent when crushed.

PHENOLOGY: Dutchman's breeches and squirrel-corn flower in spring, usually April to May. Bleeding heart flowers in early summer, June to July.

DISTRIBUTION: Dutchman's breeches and squirrel-corn are found throughout the state in rich moist woods. Bleeding heart can be found in dry or moist woods in the Commonwealth and is an "old time favorite" garden plant.

PLANT CHARACTERISTICS: Refer to the family characteristics for a general description of Dicentra. Dutchman's breeches and squirrel-corn have flowers in racemes; in bleeding heart the inflorescence is a panicle. In D. Cucullaria the outer petal sacs form divergent spurs, whereas in D. canadensis the spurs are rounded.

POISONOUS PARTS: All parts of these plants are poisonous, especially underground tubers.

SYMPTOMS: Only D. Cucullaria has been shown (experimentally) to be poisonous, at 2% of the animal's weight. Both aerial and underground portions of the plant produced symptoms within a day although these amounts were not fatal. Behavior of poisoned animals included trembling and running wildly with head held unusually high. Salivation, violent vomiting, and convulsions also were present. Shortly after the onset of symptoms, the animals fell with the head held in the position described, legs rigidly extended; and breathing labored. In one case of experimental feeding the animals could stand, although weakly, within 20 minutes after going down, and recovery was rapid and complete. Postmortem: gross and histological lesions: nonspecific.

It may be important to determine the species of Dicentra ingested in poison cases since D. canadensis failed to elicit symptoms when fed to livestock in amounts equivalent to 2 or 3% of the animal's weight, despite the presence of poisonous alkaloids in the plant.

POISONOUS PRINCIPLES: Aporphine, protoberberine, protopine, and related isoquinoline alkaloids are apparently responsible for toxicosis. More than twenty compounds structurally related to poppy alkaloids have been extracted, identified, and named from various species of Dicentra. The alkaloids cularine and several of its 0- and N- desmethyl derivatives also are present in leaves and bulbs.

CONFUSED TAXA: Corydalis is one of the few taxa that can be confused with Dicentra. A close relative whose leaves resemble those of Dicentra, it has only one sac per flower. Of the Pennsylvania species of Corydalis, both C. aurea Wild and C. flavula DC have been suspected of causing livestock loss and should be considered potentially dangerous.

ANIMAL SPECIES AFFECTED: Probably all livestock and humans.

TREATMENT: (11a) (b); (26)

OF INTEREST: These plants have been used in folk medicine to treat a variety of ailments.


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GENUS: Dieffenbachia

Dieffenbachia spp.—Dumbcane

FAMILY: Araceae—the Arum Family (see Arisaema)

PHENOLOGY: The flowering requirements of dumbcane are not often met when it is grown as a houseplant.

DISTRIBUTION: Native to tropical America, Dieffenbachia is now a favorite plant for greenhouses and interior decorations for homes and businesses.

PLANT CHARACTERISTICS: Stems: stout, green, girdled with leaf scars, unbranched, bearing leaves toward the top; leaves: entire; petioles: sheathing; leaves and petioles often spotted or variegated; flowers: unisexual; plants sometimes having a skunk-like odor when bruised. The inflorescences arise from the leaf axils on stalks shorter than the leaf petioles. The inflorescence consists of an erect spike (the spadix), which has female flowers at the bottom and male flowers at the top; the two groups of flowers are separated by a short section of naked spadix. A petal-like sheath (the spathe) enfolds the lower pistillate flowers and provides a background foil for the staminate flowers.

POISONOUS PARTS: All parts contain toxic principles, but the stems are especially poisonous. Oral administration of the toxic component (juice from plants) to guinea pigs showed an LD50 between 600 and 900 mg of stem/animal in 24 hr. Injection i.p. produced an LD50 of 1 g. A single-dose oral toxicity test in rats showed an LD50 over 160 ml/kg of the whole plant juice.

SYMPTOMS: Ingestion of dumbcane causes rapid irritation of the mucous membranes, burning, copious salivation due to release of kinins, edematous swelling and thickening of the tongue and lips, local necrosis, and difficulty in swallowing and breathing. The symptoms may last for several days to longer than a week.

POISONOUS PRINCIPLES: Mechanical and chemical actions of calcium oxalate may be partly responsible for the reaction to dumbcane. A protein (proteolytic enzyme named "dumbcain") fraction also is possibly responsible, as well as the compound asparagine.

CONFUSED TAXA: Some common cultivated house plants such as Aglacnema (Chinese evergreen) and Spathiphyllum (peace lilies) could be confused with dumbcanes. Aglacnema differs from Dieffenbachia in having inequilateral leaf bases and the spadix not united with the spathe. In Spathiphyllum the leaves are in clusters, not originating on a stout stem as in the above two genera. Two species of Dieffenbachia are commonly cultivated: D. Sequine Schott and D. maculata (Lodd,) G, Don. Hybridization and natural mutation have created many fancy-leaved forms that are exploited commercially and should be considered poisonous.

SPECIES OF ANIMALS AFFECTED: Humans and house pets are susceptible.

TREATMENT: (11a) (b); (4); (6); (9); (10); (26); (2 - i.v. diazepam); analgesics for pain (meperidine); intravenous fluids to maintain adequate hydration.

OF INTEREST: Other aroids commonly cultivated as house plants should be considered potentially toxic, including Alocasia and Colocasia (dasheen, elephant ears), Caladium (angelwings). Anthurium (tailflower), Monstera (Swiss-cheese plant, ceriman), and Philodendron (see Philodendron). In one case cattle developed severe irritation of mouth and tongue after grazing on Colocasia. Cases of severe poisoning from Alocasia, Caladium, and Xanthosoma (Blue taro, Indian Kale) have not been recorded in the U.S.


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GENUS: Digitalis

Digitalis purpurea L. - Foxglove

FAMILY: Scrophulariaceae—the Figwort Family

This group, also known as the snapdragon family, is a large, cosmopolitan collection of genera that contains many ornamental plants. Within the family apparently only foxglove is toxic.

Flowers are: bisexual, typically irregular, often 2-lipped; stamens: 4, or occasionally 2 or 5; sepals and petals: either 4- or 5-merous; ovary: superior, 2-celled; fruit: a capsule.

PHENOLOGY: Foxglove is a summer-flowering biennial often sold in garden centers already in blossom.

DISTRIBUTION: A cultivated plant, foxglove occasionally escapes and is short-lived in the wild in our range. It would be encountered more often in the flower garden

PLANT CHARACTERISTICS: This plant, native to Europe and northwestern Africa, is easily recognized by its showy, terminal, one-sided racemes of large, drooping flowers. Other characteristics include the basal leaves: in rosettes, lanceolate to ovate, long-petioled; stem leaves: alternate, simple, sessile or nearly so; calyx: 5-parted; corolla: to 7 cm long, purple to pink or white with conspicuous spots inside; stamens: 4.

POISONOUS PARTS: The herbage, both fresh and dried, contains powerful, highly toxic compounds.

SYMPTOMS: In humans toxic reactions include gastric upset, nausea, diarrhea, abdominal pain, severe headache, pulse and cardiac rhythm abnormalities, mental irregularities, drowsiness, tremors, convulsions, and death. In livestock symptoms are similar and include bloody stools, lack of appetite, and the urge to urinate.

POISONOUS PRINCIPLES:  Digitalis, an extract of foxglove, has been used medicinally for many years; hence, a large body of information has accumulated concerning it. Physiologically active chemical constituents found in foxglove include digitoxin (0.2-0.4%), digitonin, digitalin, antirhinic acid, digitalosmin, and digitoflavone. The LD50 (oral) for digitoxin in guinea pigs is 60 mg/kg of body weight, and in cats it is 0.18 mg/kg of body weight. The toxins are cardiac or steroid glycosides. The aglycones are derivatives of cyclopenteno-phenanthrene; and the sugars, unusual methyl pentoses. They influence the heart in two ways: stronger cardiac contractions and slower contractions through stimulation of the vagus, prolonging diastole. Digitalis is of much importance to modern medicine.

CONFUSED TAXA: No other garden plants produce tall, (to more than 1.5 m) one-sided racemes of purple, spotted flowers.

SPECIES OF ANIMALS AFFECTED: Humans, usually from drug overdoses, and livestock, from grazing, have been poisoned by foxglove alkaloids. Poisoning in animals can result from hay contamination in addition to browsing fresh material. Susceptible animals include pigs, cattle, horses, and turkeys.

TREATMENT: (l la)(b); (26); (5); (19).


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GENUS: Equisetum

Equisetum arvense L. - Common horsetail

FAMILY: Equisetaceae—the Horsetail Family

This family of fern allies contains only one genus—Equisetum. Plants are primitive, sporebearing, annual or perennial, rhizomatous herbs having vascular tissue.

PHENOLOGY: The fruiting period is April to July.

DISTRIBUTION: Equisetum arvense thrives in a broad range of habitats from moist to wet, or in moderately dry sandy soil; it may grow in fields, woods, on stream banks, or along roadsides.

PLANT CHARACTERISTICS: Horsetail is not a true flowering plant with sepals and petals. The reproductive structure is a sporophyll in a terminally, spikelike cone composed of shield-shaped spore-bearing structures. Other characteristics include, stem: hollow, one large central canal surrounded by smaller ones under each ridge of the stem; jointed; impregnated with silica; striated or grooved; rushlike; branches: whorled; leaves: marginally united into a sheath around each node. Plants bear nongreen reproductive structures in spring and green vegetation during the remainder of the growing season.

POISONOUS PARTS: All parts, green and dried, can be toxic. Hay containing 20% or more of E. arvense causes poisoning symptoms in horses in 2-5 weeks.

SYMPTOMS: Toxicosis is similar to bracken poisoning (see Pteridium) Apetite remains normal until near the end of the illness in Equisetum poisoning, whereas it is lost early in bracken poisoning. Ataxia, difficulty in turning, and the body wasting away followed by general weakening are early signs. In later stages animals may become constipated and the muscles rigid. Pulse rate increases and weakens, and the extremities become cold. The cornea of the eye may become opaque. Before death, the animal becomes calm and comatose. If poisoning is discovered early, the toxic plants removed from the diet, and proper nutrition given, animals can recover rapidly.

Horses are not infrequently affected by E. arvense. In advanced cases when a horse '"goes down" and cannot arise, the animal becomes nervous, making frantic attempts to stand. When a poisoned horse is exercised it will tremble and become muscularly exhausted. Cattle are not readily affected by E. arvense. In experiments with cattle, the only result was marked loss in the general condition of the animal over a forty-day period. Postmortem: gross lesions: none evident; histological lesions: diffuse lesions in the cerebral cortex such as polioencephalomalacia or cerebrocortical necrosis; bilaterally symmetrical zones of malacia involving various nuclei of the brain.

POISONOUS PRINCIPLES: The enzyme thiaminase is responsible for poisoning in non-ruminants. The previously suspected silica, aconitic acid, palmitic acid, nicotine, methoxypridine, equisitine, palustrine, and dimenthyl sulfide components are not of themselves toxic enough to produce poisoning. However, they may complicate the toxicosis. The toxic agent for ruminants is unknown and generally not fatal.

CONFUSED TAXA: No unrelated plants occurring in Pennsylvania look like species of the distinctive genus Equisetum. All members of this common genus should be considered poisonous.

SPECIES OF ANIMALS AFFECTED: Horses primarily are affected, with sheep to a lesser degree. Equisetosis is rarely fatal for cattle.

TREATMENT: (11a)(b); (26); massive doses of thiamine.

OF INTEREST: The stems, which contain silica crystals, are sometimes used to polish metal; hence the name scouring rush. Plants are occasionally used as an ornamental in moist places such as around ponds.


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GENUS: Eupatorium

Eupatorium rugosum Houtt.—White snakeroot, snakeroot

FAMILY: Compositae (Asteraceae)—the Daisy Family (see Arctium)

PHENOLOGY: Snakeroot flowers from July through October.

DISTRIBUTION: Eupatorium rugosum grows in eastern North America. Abundant in Pennsylvania, it is found in moist areas, rich open woods, and along streams. It often forms dense colonies in areas where logging has cleared regions of the forest.

PLANT CHARACTERISTICS: The heads of white flowers are small and contain only disk flowers: 3 to 4 mm long; heads: contain 10 to 30 flowers; leaves: thin, opposite, evidently petioled, sharply serrate, acuminate, the larger ones 6 (to 18) x 3 (to 12) cm long; stems: 1.5 dm, from a shallow mat of fibrous, perennating roots.

POISONOUS PARTS: The poisonous parts are the leaves and stems; toxicity decreases with drying. Seasonal or ecological variation may affect toxic principles; frost does not reduce toxicity.

SYMPTOMS: The following conditions are recorded in toxicosis: trembling, especially of the flank and hind legs; slow, lethargic or sluggish behavior ("the slows"); stiffness in movement or ataxia; coma; and death. Horses seem less prone to trembling. Livestock may exhibit constipation, nausea, vomiting, slobbering, loss of appetite, or labored or rapid breathing. An acetone odor on the breath may result from ketosis in severely poisoned animals. Postmortem: gross and histological lesions: fatty degenerative changes in liver and kidney; heart and gastrointestinal hemorrhages.

POISONOUS PRINCIPLES: Poisoning is possible due to an unstable, fat-soluble alcohol called tremetol, which has a phenyl nucleus and an incompletely characterized resin acid. Tremetol is an aromatic, straw-colored oily liquid. The principal ketone, tremetone, is also suspected to be toxic.

CONFUSED TAXA: There are more than twenty species of Eupatorium in the eastern U.S., with most encountered in Pennsylvania. Because E. rugosum may be difficult to identify accurately, any suspected material should be examined by a specialist.

SPECIES OF ANIMALS AFFECTED: Species known to be susceptible are fowl, sheep, horses, cattle, hogs, and humans; illness may be experimentally induced in various laboratory animals.

TREATMENT: (26); treat for anuria, liver, and kidney damage.

OF INTEREST: "Trembles" and "the slows" are not the only illness produced from Eupatorium toxicosis. "Milksickness" was a common disease in the Colonial period, reaching its peak in the first half of the 1800's. Since tremetol is readily excreted in milk, poisoning can occur from ingestion of milk from lactating animals that have eaten Eupatorium. During the early pioneer period, entire villages were abandoned and human population centers were reduced to less than one-half the original number due to milksickness because the etiology of the disease remained a mystery. The amount of plant consumed to elicit sickness varies from 1-20% of the animal's weight and depends on many factors. Because the toxin is cumulative, the onset of symptoms varies from less than 2 days to as much as 3 weeks. Death follows from 1 day to 3 weeks after the symptoms appear. Recovery is good if the disease can be countered before ketosis appears. In many cases, prognosis is poor and recovery is rare, slow, and incomplete. Milksickness in humans begins as a few days of weakness, loss of appetite, abdominal pain, and violent vomiting followed by obstinate constipation, severe thirst, loss of ingested fluids by vomiting, tremors, acetone breath, prostration, delirium, coma, and death. The disease can be fever-producing or the temperature may be subnormal. Mortality ranges from 10-25%, but the massive loss of human life seen in centuries past does not occur owing to current practices of animal husbandry and the pooling of milk from many producers.


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GENUS: Euphorbia

Euphorbia cyparissias LCypress-spurge

Euphorbia maculata LWartweed

Euphorbia marginata Pursh.—Snow-on-the-mountain

FAMILY: Euphorbiaceae—the Spurge Family (see Codiaeum)

PHENOLOGY: Euphorbia spp. bloom from May to September depending on the taxon.

DISTRIBUTION: More than twenty species of Euphorbia are found in Pennsylvania. They occur as weeds (Euphorbia maculata L ), as garden plants (E. marginata Pursh ), or as plants escaped from cultivation (E cyparissias L ).

PLANT CHARACTERISTICS: The Euphorbia cyathium contains staminate flowers: several, each containing one stamen; pistilate flower: one, containing one pistil; ovary: 3-celled, 3-ovuled; styles: 3; involucre: 4- to 5-lobed, usually bearing glands in the sinuses. Our plants are herbs, usually with milky, acrid juice.

POISONOUS PARTS: The whole plant, fresh or dried, is poisonous.

SYMPTOMS: Diarrhea, collapse, and death may result from ingestion of Euphorbia cyparissias. Hay contaminated with E. cyparissias has caused death in cattle.

Euphorbia maculata, growing predominantly in a pasture, caused a 30% loss of Hampshire lambs. Euphorbia maculata fed to lambs at a rate of 0.62°/c body weight caused death within hours. Surviving lambs were photosensitized so that exposure to sunlight produced edematous enlargement of the head. Toxicity may increase during July and August when rains follow a period of drought.

Euphorbia marginata produced diarrhea and emaciation, lasting several months, when 100 oz was fed to cattle. Consumption of this plant can cause blistering, irritation, and inflammation of the upper digestive tract. The sap has been noted to cause contact dermatitis on the legs and face of horses. The death of a young woman, who drank a decoction of E. marginata in an effort to abort, is reported.

POISONOUS PRINCIPLES: Irritant cocarcinogenic diterpenoids have been isolated as toxins in some Euphorbia species.

CONFUSED TAXA: Euphorbia cyparissias is a colonial plant from creeping rootstocks; leaves: linear, entire, crowded, 3 cm long, 1-nerved; cyathia: umbel-like cymes, yellowish green when young, becoming purplish red; glands: yellow, crescent shaped with 2 short horns.

Euphorbia maculata are prostrate plants growing like mats over the ground; leaves: all opposite, oblique at base, dark green, often with a median red spot: stipules: present; glands and petaloid appendages: 4. Botanists are not in full agreement as to the identity of plants to be included in this species. Some plants that may prove to be equivalent to E. maculata L., are E. supina, E. chamaesyce and E. hirta.

Euphorbia marginata grows to 2 m; leaves: alternate, sessile, broadly ovate to elliptic; leaves subtending the inflorescence: whorled; marginated with white, or entirely white; involucral lobes: fringed; appendages: 5, white, conspicuous; fruit: 3-lobed. 6-7 mm in diameter,

TREATMENT: (11a)(b); (26)

OF INTEREST: All species of Euphorbia can be expected to contain the complex esters believed responsible for poisonings and are probably capable of eliciting an allergic reaction. Reported deaths from Euphorbia poisoning are rare but livestock can be seriously affected.

Euphorbia corollata L. (flowering spurge) has been implicated in the poisoning of livestock. This widely distributed weed flowers from May though September and has 5 cyathial glands and white petaloid appendages. It has been used in small doses for diaphoresis and as an expectorant.

Euphorbia heterophylla L. (fire-on-the-mountain), commonly cultivated in the Midwest, is now becoming prevalent as an escaped plant in the East. Diagnostic characters include the absence of petaloid appendages on the singular gland of the involucre and stem leaves that are mostly alternate, glabrous above, and hairy beneath. A closely related species, E. dentata Michx., has opposite leaves with hairs on both sides. It too is found in increasing numbers on dry sites, along roadsides, and in waste places. Both are to be treated with suspicion, although no records indicate poisonings from these taxa.

Other species to be alerted to are E. Preslii Guss, E. esula L. (leafy spurge), and E. Peplus L, (petty spurge). The last-named species is locally abundant in vegetable gardens, and unconfirmed reports indicate that dogs eating a low concentrated mixture of it and grass develop violent diarrhea; it has proven lethal to human beings. Euphorbia lathyris (caper-spurge) was used as a medicinal folk remedy. This toxic species can still be found around old homesteads and as an escaped plant.

Euphorbia commonly grown as houseplants include Euphorbia Milfi Ch. des Moulins (crown-of thorns) and E pulcherrina Willd. (Poinsettia). The crown-of-thorns is a woody, spiny plant with cyathia subtended by bright red bracts. When bruised, it produces an irritant, white, milky latex. No cases of severe poisoning have been reported in the literature, but crown-of-thorns may be toxic if consumed in quantity. Poinsettias are popular Christmas-time house plants. No well documented cases of severe poisoning exist despite many cases of fruit, bud, and leaf ingestion The irritant milk may produce symptoms of gastroenteritis including abdominal pain, vomiting, and diarrhea.


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GENUS: Glechoma

Glechoma hederacea L—Ground-ivy; gill-over-the-ground; creeping charlie; runaway-robin

FAMILY: Labiatae (Lamiaceae)—the Mint Family

This is a large group of plants known for glands that secrete pungent, volatile oils that may be toxic in large amounts. Many plants in this family are cultivated as ornamentals or as sweet herbs. Characteristic features for this family include stems: square in cross section; leaves: opposite, 4-ranked, simple, without stipules, glandular; flowers: irregular; calyx: 4- to 5-lobed, 2-lipped, persistent; corolla: 4- to 6-lobed, 2-lipped, petals conspicuously united; stamens: 4 (rarely 2), inserted on the corolla; ovary: superior, deeply lobed; style: 1 from the center of the ovary lobes; fruit: 4 one-seeded nutlets.

PHENOLOGY: Ground-ivy flowers April through June.

DISTRIBUTION: Found in moist fields or woods or in disturbed soil, including roadsides and yards.

PLANT CHARACTERISTICS: Plants are prostrate or creeping; leaves: cauline, petiolate, 1-3 cm, crenate rotund-cordate to cordate-reniform; stem: retrorsely scabrous to subglabrous; pilose at the nodes; flowers: 13-23 mm across, on short pedicels; petals: blue violet, marked with purple spots; usually 3 flowers per axil.

POISONOUS PARTS: All parts are toxic in green or dried condition.

SYMPTOMS: Salivation, sweating, dyspnea, panting, dilated pupils, anxious look, cyanosis, and possibly pulmonary edema can be manifested. Postmortem: pulmonary edema and cerebral hyperaemia.

POISONOUS PRINCIPLES: Physiologically active volatile oils are responsible for toxicosis.

CONFUSED TAXA: Glecoma is sometimes mistaken for Lamium (dead nettle), but the flowers are distinctly pediceled (in loose cymules) in Glecoma and sessile (in dense cymules) in Lamium.

SPECIES OF ANIMALS AFFECTED: Apparently only horses are susceptible to Glecoma toxins.

TREATMENT: (11a)(b); (26)

OF INTEREST: Lamjum amplexicaule L., commonly encountered as an element of our spring flora, causes "staggers" in sheep, horses, and cattle. Stachys arvensis L., fieldnettle, is responsible for nervous disorders in livestock, especially sheep. It too is a Pennsylvania resident.


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GENUS: Gymnocladus

Gymnocladus dioica (L.) C. Koch—Kentucky coffee-tree

FAMILY: Caesalpiniaceae—the Caesalpina Family

The bean family, Leguminosae, is naturally divided into three subfamilies: the Faboideae, the Mimosoideae, and the Caesalpinioideae. Some authorities classify the three subfamilies as separate families as they are presented here. The Fabaceae family description is found under the Crotaiaria entry. No members of the Mimosaceae found within Pennsylvania are toxic. The Caesalpiniaceae are characterized by flowers: perfect or unisexual, regular or sometimes irregular; hypanthium: well developed, often irregular; sepals: 5; petals: 1-5; stamens: typically twice as many as the sepals; ovary: 1; fruit: a legume splitting along 2 sutures.

PHENOLOGY: Gymnocladus dioica flowers in May.

DISTRIBUTION: Kentucky coffee-tree is found in rich moist woods. It is seldom abundant, frequently occurring as single trees.

PLANT CHARACTERISTICS: Kentucky coffee-tree is a tall tree, to 30 m; plants: bear on one tree flowers partly perfect and partly pistillate, and on another tree flowers partly perfect and partly staminate; flowers: regular, perfect or unisexual, 5-merous; hypanthium: tubular, 10-15 mm; sepals and petals in a single series, 8-10 mm; stamens: 10, distinct, alternately long and short; fruit: red-brown, woody, flat. thick, often exuding a yellow resin when broken; seeds: few per pod, large, separated by pulp; branches: stout, without small twigs or thorns; leaves: very large, bipinnately compound, new leaves often pink; leaflets: 2-3 cm wide; inflorescence: terminal panicles of greenish-white flowers.

POISONOUS PARTS: The sprouts, foliage, and fruit are poisonous.

SYMPTOMS: Severe gastrointestinal irritation and narcotic-like effects on the nervous system have been reporte. Postmortem: gross and histological lesions: congestion of the mucous membranes.

POISONOUS PRINCIPLES: The cause of toxicosis is unknown but may be due to the presence of alkaloids. Cytisine, a toxic quinolizidine alkaloid, has been extracted from leaves, pods, and seeds. The LD50 orally in mice is 50-101 mg/kg, subcutaneous in dogs it is 4 mg/kg body weight.

CONFUSED TAXA: The bipinnate leaves of Kentucky coffee-tree may be confused with the bipinnate or even-pinnate leaves of honey locust (Gleditsia triacanthos L.), also in the Caesalpinaceae. Honey locust has leaflets 1 cm wide, thorns that may be branched, and flowers in spike-like racemes. The pulp of the honey locust fruit is sweet-tasting and nonpoisonous.

SPECIES OF ANIMALS AFFECTED: Kentucky coffee-tree is poisonous for apparently all classes of livestock and for humans.

TREATMENT: (11a)(b); (26)

OF INTEREST: A case exists of a woman who was poisoned after eating some fruit pulp of Kentucky coffee-tree, mistaking it for honey locust. Cases have been cited in which death occurred in sheep in less than 1 day after the appearance of symptoms. Seeds of this plant have been used for a coffee substitute.

The golden chain tree, Laburnum anagyroides Medic., a cytisine- producing legume in the Fabaceae, can cause toxicosis as well. This widely cultivated tree with long-petioled, trifoliate, alternate leaves produces hanging racemes, about 5 dm long, of golden-yellow flowers. The fruit is a legume pod containing up to 8 seeds. The seeds and flowers, eaten in large quantities, can produce poisoning characterized by excitement, gastroenteritis, dilation of pupils, incoordination, irregular pulse, convulsions, coma, and death through asphyxiation. Oral toxicity of seeds for horses is about 0.05% of the animal's weight. Treatment: (11a)(b); (26); (1); (6).


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GENUS: Hedera

Hedera helix LEnglish ivy

FAMILY: Araliaceae—the Ginseng Family

This family is of minor economic importance. Some noteworthy members include English Ivy (Hedera helix L.); Tetrapanax papyriferus (Hook.) C Koch, the source of Chinese rice-paper; and Panax quinquefolium L., the ginseng of Oriental medicine. Because only Hedera helix is of major concern here, a full description of this species replaces the family description.

PHENOLOGY: English ivy produces umbels of flowers in summer.

DISTRIBUTION: Hedera helix is a cultivated plant grown indoors as a pot subject or outside, usually as a wall or ground cover.

PLANT CHARACTERISTICS: English ivy is a trailing or climbing vine with a diversity of leaf shapes ranging from ovate, rotund to variously 3- to 5-lobed or angled, leaves: firm, evergreen; flowers: small, greenish, produced only when the branches reach a height of more than 15 feet; sepals: 5, very short; petals: 5, fleshy; stamens: 5; ovary: 5-celled, 1 style; fruit: a round, 3- to 5-seeded berry.

POISONOUS PARTS: The black berries and leaves of English ivy are poisonous if consumed in quantity.

SYMPTOMS: Hedera helix is a purgative that produces local irritation, excessive salivation, nausea, excitement, difficulty in breathing, severe diarrhea, thirst, and coma.

POISONOUS PRINCIPLES: The toxic substance is hederin, a glycoside of the steroidal saponin hederagenin.

CONFUSED TAXA: Several varieties of Hedera helix have 3 leaflets per leaf and resemble poison ivy (see Rhus radicans). There exist numerous foliage forms; many are not stable and, with age, revert to the original type. Generally, English ivy can be differentiated from poison ivy by its dark, glossy, evergreen foliage, compared to the thinner-textured, deciduous leaves of poison ivy.

SPECIES OF ANIMALS AFFECTED: Both humans and livestock show the symptoms listed above.

TREATMENT: (11a)(b); (17); (6)

OF INTEREST: Other species of Hedera, especially the popular Algerian ivy, H. canariensis Willd., as well as members of the genus Aralia (sarsaparilla) should be viewed with suspicion. The fruits of all species of Aralia are poisonous when eaten raw but are infrequently cooked as jelly, which is reported edible.


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GENUS: Helenium

Helenium autumnale L.Sneezeweed

FAMILY: Compositae (Asteraceae)—the Daisy Family (see Arctium)

PHENOLOGY: Helenium species flower late in the growing season, from August through October.

DISTRIBUTION: Sneezeweed is an inhabitant of moist low ground, rich thickets, meadows, and shores.

PLANT CHARACTERISTICS: The fibrous-rooted perennial H. autumnale grows to 1.5 m tall. The stems bear wings originating as decurrent leaf leaves: numerous, lance-linear to elliptic, almost sessile; lower leaves deciduous; heads: several or many in a leafy corymbosely branched inflorescence, or simple; disks: yellow, 8-20 mm wide; rays: toothed or lobed, 10-20, pistillate or sometimes neutral, 1.5-2.5cm long and 7-12 mm broad; pappus: keeled scales, brown, ovate, tapering into a short awn.

POISONOUS PARTS: All parts of the sneezeweed plant, especially flowers, are toxic. Experiments show 1% (dry) of a sheep's weight of Helenium will cause illness and death within 8 days.

SYMPTOMS: Early signs of Helenium poisoning are dullness and depression; weakness, tremors, and rapid respiration and pulse ensue. Nausea and vomiting may be present. Other symptoms include excessive salivation, belching, frothing, and intestinal disorders. Animals not displaying vomition will often recover. The prognosis for those vomiting is less positive.

Postmortem: gross and histological lesions: Examination reveals gastrointestinal degeneration and liver, kidney, and lung damage; hydrothorax, ascites, congestion, and edema in the forestomachs (submucosa of the rumen and reticulum); edema of nervous tissue; and sometimes mild tubular nephrosis, as well as fatty changes in the myocardium.

POISONOUS PRINCIPLES: The toxin in some species is a glycoside, dugaldin, whereas in other taxa it is the sesquiterpene lactone helenatin

CONFUSED TAXA: The combination of yellow ray and disk flowers, scaly-awned pappus, alternate leaves, and truncate style-branches without appendages are unique to Helenium. The closely related genus Gaillardia is similar except the style-branches have subulate appendages.

SPECIES OF ANIMALS AFFECTED: Sheep are apparently very sensitive to sneezeweed, but the poisonous principle will affect all livestock and humans. Sheep will eat this bitter weed when all other forage is unavailable. The toxin remains poisonous when dried; therefore, contaminated hay is also undesirable

TREATMENT: (11a)(11b); (26)

OF INTEREST: In addition to H. autumnale, several less common, introduced taxa are found in Pennsylvania: H. amarum (Raf.) H Rock, H. flexuosum Raf., and H. quadridentatum Labill.


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