Helleborus viridis L.—Green hellebore; winter-aconite
Helleborus niger L.—Christmas rose
FAMILY: Ranunculaceae—the Buttercup Family (see Actaea)
PHENOLOGY: The hellebores are late winter to early spring flowering plants.
DISTRIBUTION: Helleborus viridis is a European species that is established in some areas. Helleborus niger is a durable, cold-hardy, evergreen, ornamental plant cultivated in gardens. Both thrive in partially shaded, moist situations in good soil.
PLANT CHARACTERISTICS: The genus Helleborus is recognized by showy flowers of white, green, or purple; sepals: 5, large, petaloid; petals: none; stamens: numerous, the outer 8-10 modified into staminodes; pistils: usually 3 or 4; style: erect, slender; fruit: a follicle; leaves: alternate, palmately cleft.
POISONOUS PARTS: The entire plant is toxic.
SYMPTOMS: Helleborus poisoning includes vomiting, diarrhea, and nervous system disturbances such as delirium, convulsions, and death due to respiratory collapse.
POISONOUS PRINCIPLES: Cardiac glycosides are responsible for poisonings. Hellebrin is a cardiac stimulant found in these plants.
CONFUSED TAXA: Helleborus niger the evergreen, cold-resistant plant, produces a floral stalk but no true leafy stems. The flowers, usually borne singly on red-spotted peduncles, are white (suffused with pink). Helleborus viridis produces an erect stem with 2-4 drooping green flowers.
SPECIES OF ANIMALS AFFECTED: Both animals and humans are affected by this poisonous plant. When eaten, the hellebores are said to have a "burning taste."
TREATMENT: (11a)(b); (26).
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Heracleum lanatumMichx.—Cow parsnip
Heracleum mantegazzianum Sommier & Levl.—Giant hogweed
FAMILY: Umbelliferae (Apiaceae)—the Umbel Family (see Cicuta)
PHENOLOGY: Heracleum species flower throughout June and July.
DISTRIBUTION: Giant hogweed is native to the Caucasus Mountains and was cultivated in the U.S. as an unusual ornamental. Cow parsnip is a native plant growing in rich moist soil and low ground.
PLANT CHARACTERISTICS: The genus Heracleum contains plants that are tall, stout perennials with large compound leaves and broad, flat-topped, compound umbels with deciduous involucres and many-leaved involucels; corolla: white, peripheral flowers of the marginal umbellets irregular with the outer, bifid corolla-lobes enlarged; fruit: elliptic to obovate, dorsally strongly flattened, the lateral ribs broadly winged; oil-tubes 2-4 on the commissure, extending to about half-way down the fissure; leaves: lower ones, once pinnate; upper ones, once ternate.
POISONOUS PARTS: Upon contact, the herbage and fruits are highly irritating under the conditions described below.
SYMPTOMS: Giant hogweed produces severe, painful, burning blisters in susceptible people, the symptoms appearing within 24 to 48 hours after contact. The sap can produce painless red blotches that later blacken and scar the skin for several years. For an adverse reaction to occur the skin, contaminated with plant juices, must be moist and subsequently exposed to sunlight (see also Lantana and Hypericum). This phenomenon, known as phytophotosensitization, occurs in animals when chemical compounds, either derived directly from plants or produced by the animal in response to plant substances, are present in peripheral circulation. Heracleum lanatum has also been implicated in less severe photosensitization reactions in some people.
POISONOUS PRINCIPLES: The glycoside furanocoumarin is responsible for the severe contact dermatitis.
CONFUSED TAXA: Heracleum mantegazzianum is an herb that grows to 4 meters with leaves sometimes over 1 meter long, leafets: very large, deeply cut, green beneath; umbels: up to 1 meter across; petioles: blotched with purple, having large, coarse white hairs at the base; plants: coarsely hairy; flower stalks: ribbed. Heracleum lanatum is a smaller, less coarse (more softly pubescent) plant growing to 2 meters. Little or no purple markings are evident on the plant. Angelica atropurpurea, the purple-stemmed angelica, also a member of the Umbelliferae, has uniformly purple, hairless stems, and smaller, white-flowering flat-topped umbels less than 0.3 m in diameter.
SPECIES OF ANIMALS AFFECTED: Reports in the United States concern contact dermatitis in humans. However, photosensitization reactions can happen to livestock and pets.
TREATMENT: Washing sap-exposed skin with soap and water may help; where blisters appear: (4); (23); (26)
OF INTEREST: The recent detection of Heracleum mantegazzianum in Erie County provided the first record for this species in Pennsylvania. Other northern tier counties should remain alert for its presence; populations of the plant are known to occur 3 miles north of the Pennsylvania-New York border. It grows along roadside ditches and in moist waste areas. It has become naturalized in at least two dozen counties in central and western New York. Heracleum lanatum is reported to have medicinal properties and was once used for treating epilepsy.
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Hydrangea arborescens L.—Hills-of-snow; sevenbark
Hydrangea macrophylla (Thunb) Ser.—Hydrangea
Hydrangea paniculata Siebold—PeeGee hydrangea
FAMILY: Saxifragaceae—the Saxifrage Family
The only member of this large and diverse family with known poisonous properties is Hydrangea. The characteristics of Hydrangea, provided below, replace the family description.
PHENOLOGY: The introduced common garden hydrangea, H. macrophylla, flowers in midsummer. The native tree hydrangea or hills-of-snow (H. arborescens) is found blooming June and July, while the introduced PeeGee hydrangea (H. paniculata) flowers later in the season, during August and September.
DISTRIBUTION: The garden hydrangea is a well known, "old fashioned" ornamental cultivated for display in outdoor plantings, pots, or tubs. The hills-of-snow is a garden cultivar of the native H. arborescens that is found on dry or moist rocky woods and hillsides. The PeeGee hydrangea, H. paniculata, is a native of eastern Asia, also used in landscaping.
PLANT CHARACTERISTICS: The hydrangeas mentioned above have leaves: deciduous, opposite, petioled, toothed; flowers: in flat-topped or globular terminal cymes, often with the outer flowers sterile and much enlarged relative to the inner ones, ranging in color from white to pink, lavender, or blue; flowers: 5-merous; sepals: showy; ovary: inferior, or nearly so; fruits: dry capsules containing many small seeds.
POISONOUS PARTS: The leaves and buds contain the poisonous constituents.
SYMPTOMS: Under certain conditions the toxins produce gastrointestinal upset, nausea, diarrhea (bloody), and vomiting.
POISONOUS PRINCIPLES: Research indicates that hydrangea sometimes contains a cyanogenic glycoside, hydrangin. Other constituents include saponin, resins, fixed and volatile oils, and starch.
CONFUSED TAXA: The hydrangeas are popular cultivated plants not easily confused with other taxa.
SPECIES OF ANIMALS AFFECTED: Both livestock and human cases have been reported. Sickness was painful but recovery occurred.
TREATMENT: (11a)(b); treat for cyanide poisoning.
OF INTEREST: Analysis of poisoned victims does not always show symptoms compatible with cyanide poisoning. Roots of H. arborescens were used by American pioneers in the treatment of dyspepsia.
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Hypericum perforatumL..—St. John’s wort
FAMILY: Hypericaceae—the St John's wort Family
Native to temperate and tropical regions, this family of few genera has leaves: opposite or whorled, simple, entire, usually translucent-dotted or black-dotted; flowers: usually yellow, regular, bisexual; petals: separate; stamens: numerous, often united into clusters; styles: separate; fruit: a capsule.
PHENOLOGY: Hypericum perforatum flowers over an extended period, June through September.
DISTRIBUTION: The genus Hypericum provides several ornamentals for borders, rock gardens, ground-covers, or landscape shrubbery. H. perforatum has become an abundant weed of fields, meadows, roadsides, pastures, and waste places.
PLANT CHARACTERISTICS: Hypericum perforatum is a perennial, 4-8 dm, with many upright, leafy branches that are sharply ridged below the base of each leaf; leaves: linear-oblong, 2-4 cm on the main stem, half as long on the branches; inflorescence: cymose, flat topped, terminal; flowers: numerous; sepals: 4-6 mm, with few or no black dots; petals: 8-10 mm, black-dotted along the margin; stamens: in 3 clusters; styles: 3; seeds: 1-1.3 mm.
POISONOUS PARTS: All parts of the plant that bear the black dots, including petals and herbage, are poisonous.
SYMPTOMS: The black glands contain a toxin that is a primary phytophotosensitizer. These compounds are absorbed through the digestive system without alteration. In the circulatory system of mammals the chemicals damage the liver. In the presence of sunlight, skin develops dermatitis. Animals with normally dark pigmented skin are less likely to develop skin lesions. Hypericum perforatum produces intense dermal itching associated with aberrant behavior. Animals may experience convulsions prior to death. Often mucosa and eye epithelium are highly irritated. Blindness and starvation may precede death. Additional symptoms include elevated temperature, increased respiration and heart rate, and diarrhea.
Postmortem: gross lesions: dermatitis, conjunctivitis; skin lesions in cattle on teats, udder, and escutcheon; in sheep on head, ears, lips, eyelids, and coronet; skin changes proceed from reddening to edema, fluid weeps from the skin under necrotic tissue, and sloughs. In cattle, wounds heal slowly (approximately 2 weeks) and produce hairless scars. Death may result from infection and gangrene. Pyridine extracts of mouth, nasal and conjunctival mucosa, and digestive tract produce a light-red fluorescence under Wood's UV light; histological lesions: skin lesions including hyperemia, edema, necrosis. and ulceration.
POISONOUS PRINCIPLES: The toxic chemical probably is hypericin, a derivative of dianthrone. Previously, two substances, a volatile oil and hypericum red, were implicated. It has recently been suggested that a pigment, probably a mixture of numerous polyhydroxy derivatives of helianthrone, are responsible for primary photosensitization.
CONFUSED TAXA: More than a dozen species of Hypericum occur as native or naturalized plants in Pennsylvania; several additional species are cultivated in gardens. Although only H. perforatum is reported in the literature as poisonous, numerous other species produce black, glandular dots, which may prove to contain hypericin or related phytotoxins.
SPECIES OF ANIMALS AFFECTED: Humans, cattle, goats, sheep, and horses are reported to be affected.
TREATMENT: (11a)(b); (26); avoid direct sunlight after ingestion.
OF INTEREST: The active compound hypericin has a tonic and tranquilizing action on humans in very small quantities. Hay contaminated with dried St. John's wort is toxic since hypericin is stable upon drying and resistant to destruction by heat.
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FAMILY: Aqutfoliaceae—the Holly Family
The holly family is represented in Pennsylvania by two genera: common holly, Ilex, and mountainholly with a single species, Nemopanthusmucronatus(L.)Trel. The genus Ilex is of concern due to its mildly poisonous berries. The family consists of trees or shrubs; leaves: simple, alternate; stipules: minute, caducous; flowers: small, 4-merous, often unisexual. Many species are dioecious, containing plants that bear only male or female flowers.
PHENOLOGY: Hollies generally flower in May or June. The berries of most holly plants begin ripening in late autumn.
DISTRIBUTION: Ilex is encountered in Pennsylvania as ornamentals or as native or escaped plants. The evergreen, ornamental hollies are found in landscaping around the home where the soil is rich, acidic, and well drained. Many of the native species prefer wet woods or swamps.
PLANT CHARACTERISTICS: Most species of Ilex have flowers: axillary, small, greenish white, unisexual, male and female borne on separate plants; pistillate flowers: bear stamens with reduced anthers; stammate flowers: produce as many stamens as the number of petals, often with a vestigial pistil; calyx: 4-6 lobed; petals: 4-8, slightly fused at base; fruit: a red or black berry.
POISONOUS PARTS: The berries of Ilex are mildly poisonous.
SYMPTOMS: Holly berries produce gastrointestinal disturbances (vomiting, diarrhea) and stupor when consumed in large amounts.
POISONOUS PRINCIPLES: The toxin is unknown.
CONFUSED TAXA: Holly and holly berries are easily recognized by most people because of their popularity.
SPECIES OF ANIMALS AFFECTED: Small children are most likely to be poisoned from ingestion of holly berries.
TREATMENT: (11a)(b); (26)
OF INTEREST: The steeped berries of American holly, Ilex opaca, have been used by Amerindians as a cardiac stimulant. The dried leaves have been used by colonists and immigrants as a substitute for tea, especially during the American Civil War. Care should be taken during the Christmas season to keep children away from Ilex berries.
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FAMILY: Convolvulaceae—the Morning-glory Family
This moderate-sized family contains twining herbs, often with milky juice; leaves: alternate, in our range simple and lobed; flowers: large, brightly colored, regular, and bisexual; calyx: 5-parted; corolla: funnelform, pleated; buds: frequently twisted; stamens: 5; ovary: superior.
PHENOLOGY: Generally all species flower July throughout September.
DISTRIBUTION: Some of the Ipomoca species are cultivated; some such as I. purpurea (L ) Roth have escaped and are found in uncultivated situations. Still others, such as I. pandarata (L.) G.F.W Meyer, are native plants. Many occur as weeds of fields, roadsides, thickets, and waste places.
PLANT CHARACTERISTICS: Morning-glories have the following characteristics; sepals: 5, imbricate, often unequal; stamens and style not exsert from corolla; leaves: cordate or lobed.
POISONOUS PARTS: The leaves and stems are toxic, while the seeds in some species are hallucinogenic.
SYMPTOMS: Ingestion of vegetation causes purgation and gastrointestinal distress accompanied by explosive diarrhea, frequent urination, and depressed reflexes. Prolonged consumption results in anorexia, wasting-away, depression, dyspnea, coma, and in severe cases, death. Consumption of seeds causes nausea, psychotic reactions, and hallucination.
POISONOUS PRINCIPLE: The toxins in Ipomoca foliage are unknown. The hallucinogenic principle in seeds of I. tricolor Cav. is D-lysergic acid amide (ergine) and possibly other ergot alkaloids. The seeds are estimated to contain 3 mg of alkaloid per gram. This compound is similar to LSD-25, a hallucinogen.
CONFUSED TAXA: All native and naturalized morning-glories should be considered toxic. The seeds of the commonly cultivated I. tricolor and cultivars (‘Blue Star’, ‘FIying Saucers’, ‘Heavenly Blue’, ‘Pearly Gates’ ‘Summer Skies’, ‘Wedding Bells’, etc.) are dangerous. The genus Convolvulss (bindweed) differs from Ipomaca in that the former has 2 stigmas, whereas the latter has one. Consumption of bindweed foliage is also reported to cause gastric distress.
SPECIES OF ANIMALS AFFECTED: Livestock have developed the symptoms described above after consuming leaves and stems. Especially susceptible are hogs, sheep, cattle, and goats. Humans have been poisoned from an overdose of hallucinogenic seeds.
TREATMENT: (11a)(b); (26)
OF INTEREST: As a hallucinogen, morning-glory seeds are estimated to be about 1/10 as potent as LSD.
It should be noted that many seed distributors apply fungicides to seeds prior to packaging. Consumption of treated seeds can cause additional sickness, including severe vomiting, diarrhea, or physiological problems.
In Mexico the Aztecs used seeds of Ipomoea and the related genus Rivea as a hallucinogen in religious ceremonies and in medicine.
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Iris spp.—Iris; flag
FAMILY: Iridaceae—the Iris Family
In addition to the well known cultivated and native or naturalized species of Iris, other members of the family found in our range include the blackberry-lily, Belamcanda chinensis (L ) DC.; gladeolus, Gladeolus spp; and blue-eyed grass, Sisyrinchium spp. Owing to the familiarity of this group, especially the irises, no family description is given.
PHENOLOGY: The flowering time of irises varies, with early-flowering species producing showy blossoms in April and others blooming as late as July. Generally, most irises in our range flower in May.
DISTRIBUTION: Irises thrive in habitats ranging from sandy, open woods to swamps. Many types are garden cultivars, grown around the home for ornamental purposes.
PLANT CRARACTERISTICS: The petals and sepals are not readily distinguishable; outer tepals: spreading or reflexed; inner tepals: erect or arching; stamens: inserted at base of outer 3 tepals; ovary: 3-6 angled; style: divided distally into 3 petaloid branches arching over the stamens, each 2-lobed at the tip; perennial herbs with linear leaves growing from a horizontal rhizome.
POISONOUS PARTS: The roots, and to a lesser extent the leaves, are poisonous upon ingestion in quantity. The roots may produce dermatitis in sensitive individuals.
SYMPTOMS: Ingestion of iris leads to gastroenteritis, purgation, and dyspnea. Contact dermatitis and irritation may result.
POISONOUS PRINCIPLES: The toxins are largely unknown. The irritant principle may be irone, a glycoside.
CONFUSED TAXA: The flowers of iris are unmistakable. The leaves may be confused with cat-tail (Typha spp ), sweet flag (Acorus spp ), or some larger sedges (Carex spp ).
SPECIES OF ANIMALS AFFECTED: Livestock and humans have been poisoned after eating large quantities of iris.
TREATMENT: (11a)(b); (26) for ingestion; (23) for dermatitis
OF INTEREST: Toxic reports are rare, probably due to the large quantity of material needed for poisoning. Iris root has been used medicinally as a purgative. Chemical constituents include iridin (an oleoresin), isophthalic acid (an unknown camphoraccus substance), gum, tannin, sugars, and oils, The seeds of iris have been used as a coffee bean substitute, a practice not advised. The pulped raw rhizome of I. missouriensis was used to relieve tooth ache.
Gladeolus spp have been listed in older literature as poisonous, but this could not be substantiated in recent references to poisonous plants.
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Kalmia latifolia L—Mountain laurel
FAMILY: Ericaceae—the Heath Family
Widely distributed on acid soils, members of this family are found mostly in the northern temperate region. Characteristics include: flowers: regular, bisexual, and perfect; petals: usually united; leaves: alternate, opposite, or whorled on the stems; stamens: as many or twice as many as the petals; calyx: 4-7 lobed, often S; corolla: often urceolate; anthers: often appendaged, frequently opening by a terminal pore; pistil: 1; carpels: 5; style: 1; fruit: a capsule.
PHENOLOGY: Mountain laurel flowers May through July.
DISTRIBUTION: Woodlands on rocky or sandy acidic soil.
PLANT CHARACTERISTICS: Shrubs or small trees, 2 to 10 m high; petioles: 1-2 cm; leaves: evergreen, alternate, glabrous, 5-10 cm long, margin entire, dark green above, bright green below; flowers: terminal; corolla: white to rose with purple markings; anthers: held in chambers on the corolla tube until pollination; fruit: a dry, 5-celled septicidal capsule.
POISONOUS PARTS: Flowers, twigs, pollen grains, and green plant parts cause toxicity. Percentages of Kalmia (relative to animal's body weight) needed to produce symptoms, but not death, are: 0.15% (sheep), 0.2-0.4% (cattle and goats), and 1.3% (deer).
SYMPTOMS: In order of appearance, symptoms are: anorexia; repeated swallowing or eructation and swallowing of cud without mastication; profuse salivation; watering of the mouth, eyes, and nose; loss of energy; slow pulse; low blood pressure; incoordination; dullness; depression; vomiting; and frequent defecation. As poisoning progresses, animals become weak and prostrate. Difficulty in breathing is common and there is no pupillary refex; death is preceded by coma. Symptoms are similar for all classes of livestock; the time for the appearance of symptoms averages 6 hours. Postmortem: nonspecific gastrointestinal irritation and hemorrhage.
POISONOUS PRINCIPLES: Andromedotoxin and arbutin are responsible for toxicity. Andromedotoxin, a resinoid, causes vomiting by directly stimulating the vomition center; its structure is not fully known. Arbutin is a glucoside by hydroquinone.
CONFUSED TAXA: Three species of Kalmia occur in Pennsylvania: K. angustifolia L. with lateral flower clusters and K polifolia Wang and K latifolia L. with terminal flower clusters Kalmia polifolia has opposite leaf arrangement (as does K. Iatifolia, which can also have ternate leaves), whereas K. latifolia has alternate leaves.
SPECIES OF ANIMALS AFFECTED: Apparently all species of animals can be poisoned by mountain laurel. Sheep are the most susceptible of animals, cattle are next. Monkeys, angora goats, and humans have been poisoned by mountain laurel.
TREATMENT: (11a)(b); (1); (5); ( 12)
OF INTEREST: The Delaware Indians used laurel for suicide. Experiments indicate that fowl can eat relatively large quantities of mountain laurel without developing symptoms. When fed to cats, the meat was toxic. Humans have been poisoned by andromedotoxin in pollen after eating honey suspected to have been made from members of the Ericaceae.
The toxin arbutin is used commercially as a stabilizer for color photographic images and in veterinary science as a diuretic and urinary anti-infective. Many members of this family contain these or similar toxins. Evergreen plants are more commonly the cause of poisoning than the deciduous species. Plants in this family that occur in Pennsylvania and cause sickness or death similar to that described above include Ledum groenlandicum Oed., Labrador tea; Pieris japonica (Thunb,) D, Don, Lily-of-the-valley bush (commonly cultivated); and possibly Menziesia pilosa (Michx.) Juss.
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Lantana Camara L.—Lantana; yellow sage; red sage
FAMILY: Verbenaceae—the Vervain Family
This family is widespread in the tropics but sparingly represented in cool regions. None of the twelve or more species of Verbena occurring in Pennsylvania are toxic. The plant in this family that can be a problem is Lantana Camara, a common florist's subject, propagated in greenhouses and hanging-baskets. In Florida it is one of the most common causes of poisonings. Because no other members of the Verbenaceae are toxic, a family description is replaced by the plant characteristics listed below.
PHENOLOGY: Lantana is propagated by softwood cuttings and seeds. In our area it is a hot-house plant that is flowering when purchased, usually during spring and summer months.
DISTRIBUTION: Lantana Camara is found in homes, shopping malls, and greenhouses. It is most frequently sold in hanging-baskets.
PLANT CHARACTERISTICS: As a potted plant lantana becomes bushy and produces abundant flowers; stems: square; leaves: opposite, ovate, crenate-dentate, to 25 cm long, rough above, aromatic when crushed; inflorescences: flat-topped heads to 5 cm across, orange-yellow or orange changing to red, or white; peduncles: axillary, longer than the leaves; flowers: tubular, 4-parted, small; fruits: black (greenish when immature), fleshy, one-seeded drupes, 6 mm in diameter.
POISONOUS PARTS: The green, unripened fruit is very dangerous. Leaves of lantana also have yielded toxic principles upon extraction. Feeding studies indicate that lantana is quite poisonous. About 1% (green-weight basis) of body weight is sufficient for bovine toxic reactions. Fresh lantana fed to sheep produced acute symptoms and death within 5 days at about 2% of the animal's weight.
SYMPTOMS: Toxicosis produces gastrointestinal distress, vomiting, bloody-watery diarrhea, muscular weakness, ataxia, visual disturbances, lethargy, circulatory failure, and death. In acute cases lantana toxicity resembles atropine poisoning. The degree of poisoning depends on the amount of plant consumed and the degree of exposure to sunlight. Lantana contains toxins that cause organisms to react when exposed to the sun (photosensitization, see also Heracleum and Hypericum). Postmortem studies reveal degenerative changes in the liver and lesions of gastroenteritis. Edema and hemorrhages in some organs can occur in chronic cases.
POISONOUS PRINCIPLES: The alkaloid lantanin and a triterpene derivative, lantadene A, are implicated in poisonings.
CONFUSED TAXA: No other hanging-basket or potted plant from the greenhouse has the characteristics described.
SPECIES OF ANIMALS AFFECTED: Children have died after consumption of unripened berries. Beef and dairy cows are reported to succumb to browsing of lantana.
TREATMENT: (11a)(b); (26)
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Lathyrus spp.—Vetchling; wild pea; flat pea
FAMILY: Fabaceae (Leguminosae)—the Bean Family (see Crotalaria)
PHENOLOGY: The vetchlings flower in summer, generally June through September. A few species flower earlier.
DISTRIBUTION: The genus Lathyrus is represented by at least a half dozen species in Pennsylvania. The native taxa generally are found in a diversity of habitats: L. ochroleucus L, dry or moist soil, slopes and rocky banks; L japonicus Willd., gravelly shores; L. palustris L, shores, damp thickets, meadows; L. venosusMuhl., rich woods, thickets, and banks of streams. The introduced taxa (L. aphaca L., L. tuberosa, and L. Iatifolius L.) either escape from cultivation to roadsides, thickets, and wasteplaces or are grown for ornamental value.
PLANT CHARACTERISTICS: Our species of Lathyrus are characterized by plants that vine; stems: winged or angular; leavres: alternate, even-pinnate, terminating in tendrus; stamens: diadelphous; pods: fat, dehiscent legumes.
POISONOUS PARTS: Of primary concern is the pea-like seed of some species. The foliage will also produce symptoms.
SYMPTOMS: Even moderate amounts of Lathyrus seeds in the diet do not produce poisonings. The development of lathyrism is apparent after consumption of large quantities or an exclusive diet of seeds. Lathyrism is well documented in human history when war, poverty, or drought have altered the diet of the people in a region. Human symptoms include paralysis (with loss of bladder or bowel control); slow, weak pulse; muscle tremors; a posture of feet turned-in, toes down; sensory disturbances; convulsions; and death.
Horses probably are the animals most sensitive to the toxic principles. They display symptoms similar to those cited above and also hind leg paralysis, dyspnea, and roaring. In toxicity experiments in rats, L. Iatifolius produced nervous symptoms of hyperexcitability, convulsions, and death.
POISONOUS PRINCIPLES: Numerous compounds have been extracted from various species of Lathyrus. One compound, L-alpha, gamma-diaminobutyric acid, isolated from L. Iatifolius, produces the symptoms described in the rat experiments noted above.
CONFUSED TAXA: The vetchlings (Lathyrus), which resemble the vetches (Vicia), differ in having wing petals separate from keel petals, and a fattened style, bearded on the inner face.
SPECIES OF ANIMALS AFFECTED: Both humans and livestock have been poisoned by Lathyrus.
TREATMENT: (11a)(b); (26); a change of diet, thereby removing the toxic principles, can alter the progress of the poisoning.
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FAMILY: Oleaceae—the Olive Family
In Pennsylvania this small family is represented by both native and introduced species and contains such non-toxic plants as our familiar ash trees (Praxinus) and the cultivated plants forsythia (Forsythia) and lilac (Syringa). Economically, the family contributes plant material for ornamental and shade use, and in warmer climates provides the Mediterranean olive (Olea) for its edible fruit. The privet hedges (Ligustrum) produce poisonous berries and are included in this treatment. Family characteristics are leaves: primarily opposite; calyx: commonly 4-lobed; corolla: 4-lobed; stamens: 2; ovary: superior, 2-celled; fruit: a berry, drupe, capsule, or samara
PHENOLOGY: Ligustrum produces intensely strong-scented flowers in June and July.
DISTRIBUTION: Four species of privet, all introduced from Europe or Asia, are cultivated in Pennsylvania. They escape to thickets, open woods, roadsides, and borders of woodlands.
PLANT CHARACTERISTICS: These woody deciduous shrubs, commonly cultivated for hedges, have handsome foliage and a profusion of white flowers. Leaves: opposite, simple, entire, often thick and lustrous-green, oblong or ovate, 2.5-6 cm long; flowers: in pyramidal panicles terminating branches and branchlets; calyx: short-tubular, 4-toothed; corolla: 4-lobed; stamens: 2, inserted on the corolla tube; berry: black when mature, 1-2 seeded, hard, becoming dry and papery.
POISONOUS PARTS: The vegetation and berries are poisonous.
SYMPTOMS: The foliage and fruit produce severe gastroenteritis, pain, vomiting, and death.
POISONOUS PRINCIPLES: In Ligustrum the toxin is believed to be an unknown glycoside.
CONFUSED TAXA: This common hedge is familiar to many. No other cultivated or native shrub appears like privet, described above.
SPECIES OF ANIMALS AFFECTED: Although poisoning is rare, humans (children), as well as horses, sheep, and cattle, have suffered from consumption of Ligustrum.
TREATMENT: (11a)(b); (26)
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