POISONOUS PLANTS 



POLEMONIUM 



2729 



sumac, Rhus vernix (Fig. 3089), with pinnate leaves. 

 Both of these plants have white fruits and hence are 

 easily distinguished from the non-poisonous sumacs. 

 The poison ivy is everywhere in the eastern states along 

 roads, fence-rows and uncultivated ground, while the 

 poison sumac grows in swamps and is less common. 

 Both are skin-irritants, causing what physicians call 

 dermatitis. If the susceptible person thinks he has 

 come into contact with the plants, he should wash 

 his hands and face with alcohol, as this dissolves and 

 removes the non- volatile oil, toxicodendrol. Smoke 

 from a brushwood fire containing these plants is toxic, 

 and so is the Japanese lacquer made from the inspis- 

 sated juice of a sumac, Rhus vernicifera. Unfortunately, 

 all parts of these plants are virulent and at all seasons 

 of the year. One of the best remedies is an alcoholic 

 solution of sugar of lead, and the extract of grindelia 

 (sold at drug-stores) is sometimes used. Local remedies 

 are fresh bean leaves, stems of touch-me-not (Impa- 

 tiens) and plantain leaves (Planiago lancedata). At 

 least, these leaves allay the burning sensation of the 

 inflamed skin. An authoritative work on toxic plants 

 is the "Manual of Poisonous Plants," by L. H. Pam- 

 mel, professor of botanv in Iowa State College of Agri- 

 culture, in two parts, Part I (1910) and Part II (1911) 

 with a total of 977 pages. Other publications have been 

 issued. 



Two plants much in prominence at the present time 

 in Wyoming on account of their poisonous effect on 

 livestock are discussed by H. G. Knight, as follows: 

 'Woody aster, Xylorrhiza Parryi (Fig. 3090), is found 

 throughout the state of Wyoming, but is confined to 

 certain districts characterized by a gumbo clay soil, 

 more or less intermixed with gravel and containing more 

 or less of alkali and other salts. This plant probably 

 causes greater losses among sheep in the state of Wyo- 

 ming than all other poisonous plants together, but may 

 be easily recognized by those familiar with the range. 

 So far as is known, sheep are the only species of range 

 animal susceptible to poisoning by woody aster. No 

 antidote is known and there is much question whether a 

 satisfactory antidote will be obtained as the action of 

 the poison is powerful and death comes speedily with 

 many pathological changes." 



Pammel writes, "Death camas, Zygadenus interme- 

 dius, is a near relative of the better known Zygadenus 

 venenosus. In Wyoming the most common species is the 

 Z. intermedium and the greatest losses noted have 

 occurred in early spring when the plant is in bloom, and 

 before early forage is plentiful. The plant grows on the 

 sandy plain as well as in the drier and stonier foothills. 

 It has been found that the poisonous -properties are 

 due to the presence of alkaloids, one of which at least 

 is new to science. An antidote has not as yet been 

 determined." J OHN \^ HAKSHBERGER. 



POIVREA (N. Poivre, 1719-86; intendant of Mau- 

 ritius). Combretacese. Mostly climbing shrubs: Ivs. 

 opposite or alternate, entire: spikes axillary and termi- 

 nal; calyx 5-lobed; petals 5; stamens 10, protruded; 

 ovary 2-3-ovuled: fr. oval or oblong or 5-winged; 

 seed solitary, pendulous, 5-angled. It includes a S. 

 African shrub with orange-red fls. cult, in S. Fla. and 

 Calif. The genus is referred by Bentham & Hooker 

 to Combretum, a large genus containing some hand- 

 some plants that are little known. Poivrea differs from 

 the other combretums chiefly in the convolute cotyle- 

 dons. P. bracteosa, Hochst. Unarmed shrub 8-10 ft. 

 high: Ivs. opposite or in 3's, 2%-3x 1-1% in- petals 

 clawed, reddish, 4 lines long: fr. oval, indistinctly 5- 

 angled. Called "hiccup-nut" in Cape Colony. P. com- 

 6sa, Sweet. A large cumber with great panicles of 

 blood-red fls. : fr. short-stalked, notched at both ends. 

 Trop. Afr. B.R. 1165 (as Combretum comosum). 



POKER PLANT: Kniphofia. 



POKEWEED: Phytolacca. 



POLANISIA (Greek, many, unequal, referring to the 

 stamens). Cappandaceae. Annual herbs, mostly 

 glandular and having an unpleasant odor: Ivs. pal- 

 mately 3-5-foliate, the uppermost reduced to bracts 

 of the racemose fls.: fls. whitish or yellowish; sepals 

 4, lanceolate, deciduous; petals slender or clawed; 

 receptacle depressed, bearing a gland at the base of the 

 ovary; stamens 8 to numerous, somewhat unequal: fr. 

 a nearly or quite sessile pod. About 30 species, natives 

 of temperate and tropical regions, of little value horti- 

 culturally. P. trachysperma, Torr. & Gray. A branched 

 glandular-pubescent viscous annual, 1-2 ft. high: Ivs. 

 petioled, with 3 oblong If ts. : fls. yellowish white in termi- 

 nal racemes, rather large: fr. a caps, more or less con- 

 tracted at base, not stipitate. N. Amer. Intro, abroad. 



POLEMONIUM (ancient name, not explained; 

 probably not from Greek polemos, war, but rather the 

 philosopher Poleman). JACOB'S LADDER. GREEK 



3090. Woody aster (Aster, or Xylorrhiza, Parryi), a poisonous 

 plant of the Plains. 



VALERIAN. Polemoniaceae. Flower-garden herbs, with 

 pinnate leaves and pretty blue, purplish white or 

 yellowish flowers. 



Perennials, rarely annuals or biennials, tall or dwarf, 

 often viscid, often with a creeping rhizome which is 

 thick or slender: Ivs. alternate, odd-pinnate or pinnati- 

 sect: fls. in racemes or thyrse-like panicles; calyx in- 

 creasing after anthesis; corolla tubular, funnel-shaped, 

 broadly bell-shaped or subrotate, 5-lobed, the lobes 

 mostly obovate; stamens 5, alternate, with corolla-lobes 

 inserted near the base, included or exserted: caps. 3- 

 valved. Closely allied to Gilia and distinguished by the 

 declinate stamens and the filaments usually pilose- 

 appendaged at the base. Brand, in the recent mono- 

 graph (Engler's Pflanzenreich, IV. 250, hft. 27, 1907) 

 accepts 29 species; mostly W. N. American, extending 

 into Mex., but also in Eu., Asia and 2 in. S. Amer. 



This genus includes the Jacob's ladder, P. c&ruleum, 

 an old-fashioned inhabitant of cottage gardens, which 

 owes its popular name to the regular manner in which 

 the numerous leaflets are arranged on the long leaves. 

 It. is a hardy perennial herb, growing 1 to 3 feet high 

 and bearing five-lobed bell-shaped flowers of blue or 

 white, and nearly an inch across. Probably the finest 

 species, however, is the plant known to afl gardeners 

 as P. Richordsonii, which is a form of P. humile (or 

 P. lanotum) that has doubled or trebled in size in culti- 

 vation. A fine specimen of P. Richardsonii may have a 

 terminal cluster 6^ inches across and 5 inches deep, 

 with two dozen flowers each \% inches across. P. 

 confertum differs in the great density of its inflores- 

 cence, and by connoisseurs in alpine plants may be 

 regarded as a very fine species. Most of the yellow- 

 flowered forms are disappointing. Polemoniums are of 

 easy culture in any deep rich loamy soil. P. caeruleum and 

 P. reptans do well in partly shaded places not too dry. 



