Relatively few plants bear 3-parted compound leaves. Several opposite-leaved species and the prickly brambles are in this category. In addition, a blackberry (flufcus canadensis L.) and a rose (Rosa blanda Ait,) may lack prickles and also bear 3-parted leaves. They more closely resemble the species drawn on Plate 23 than they do these thornless trifoliates, The following thornless plants are those outside the genera Rubus and Rosa which have alternate trifoliate leaves. See also Boston Ivy (p. 188).
POISON-IVY Rhus radicans L, p. 154
Recognition: DANGER: DO NOT TOUCH THIS PLANT All parts contain a dangerous skin irritant. Grows as an erect shrub, trailing t iw\ or climbert Leaves 3-parted and long-stalked but otherwise variable, They may be stiff and leathery or merely thin, somewhat hairy beneath or not, shiny or dull, coarse-toothed and wavy-edged, or neither. Poison-ivy leaves may be somewhat reddish but this occurs only in young or in dying leaves. End leaflet has longer stalk than side ones and has pointed tip. Twigs are brown and, if climbing, have many short aerial rootlets. Old stems of climbing vines densely covered with dark fibers. Aerial rootlets and fibrous coverings lacking in upright specimens. Buds visible, hairy, without scales, pinched at base. Leaf scars large, with a half-dozen or so bundle scars. Upright plants usually are branches of underground stems and occur in thickets. Leaves 4"-14". Height 2-5' (HY) when not climbing. Flowers small, yellowish, May-July, Fruits small, smooth, white, ball-shaped, clustered, Aug.-Nov. or longer. Similar species: Poison-ivy and (1) Poison-oak (see next) are the only common thornless alternate-leaved woody plants with 3-parted leaves and visible buds. In winter, even upright form can be distinguished by numerous bundle scars and stalked hairy buds. Long stalks of end leaflets and white fruits are additional, though seasonal, field marks. Poison-ivy is the only alternate-leaved vine climbing by aerial rootlets and the only one with fiber-hairy stems. Roth (2) Fragrant Sumac ant I (3) Hoptree have hidden buds and short-stalked end leaflets; (4) Cissus (p. 132) and (5) Boston Ivy (p. 188) climb by tendrils. (6) "Five-leaved Poison-ivy" is an unsuitable name sometimes used for the pretty and harmless Virginia Creeper. (7) See also Ashleaf Maple (p. 52).
Remarks: All parts of the plant contain a heavy nonvolatile oil that causes inflammation of the skin, with blisters and swelling, in susceptible persons. Individuals vary in reaction but the
IV. ¡ HORNLESS TRIPOLIATES
skin must come in direct contact with the dangerous oil or with the smoke from burning Poison-ivy in order to be irritated. Anyone who learns to recognize the plant and avoids it and anything that comes in contact with it wilt not he affected. The old saying "leaflets three, let it be* provides adequate warning when the plant is in leaf.
Contact with the plant usually results in itching and other symptoms within a few hours. Washing the exposed parts of the body with a thick lather of yellow laundry soap is of value soon after exposure. Water alone, unless in large amounts, may only serve to spread the oil. Mild irritations may be treated with mild astringent lotions but cases of ivy poisoning involving the eyes or genitals and widespread irritations of other parts of the body should be treated promptly by a physician. The merits of taking injections for the prevention of ivy poisoning is a matter for medical opinion.
Despite poisonous effects of the plant on humans, the truits are relished by over 60 species of birds, including the bobwhite, pheasant, prairie chicken, ruffed and sharptail grouse. Many seeds are passed undamaged through their digestive systems and distribution of Poison-ivy is thus aided.
Recognition: DANGER: A southern species generally similar to Poison-ivy but always erect. Leaflets varied, blunt-tipped, obviously hairy on both sides. They may be lobed somewhat like oak leaves. Fruits usually hairy. Some authorities believe differences between the several forms of Poison-oak and Poison-ivy are inconsequential and that all probably should be grouped under one name. The irritating effects of Poison-oak are similar to those of Poison-ivy. Height to 10'. lowers
May-June, Fruits Aug.-Now or longer. Sandy and gravelly soils of Coastal Plain, New Jersey, and Maryland to Ilorida and e. Texas, and v Missouri, e. Oklahoma, and Tennessee to Texas.
Recognition: A low bush or rambling shrub with 3-parted large-toothed leaves that have a pleasant odor when crushed. Knd leaflet short-stalked. Twigs brown, bark smooth; aerial rootlets and fibrous coverings not present. Leaf buds hidden beneath round leaf scars; end buds false. Bundle scars numerous. Flower buds clustered in dense spikes, present at twig tips from late summer to spring. Leaves 4"-6". Height to 7\ Flowers small, greenish» April-July. Fruits smalU hairy, red, ball-shaped, clustered, May-July.
Similar species: Aromatic leaves, hidden buds, circular leaf scars, and winter flower spikes are distinctive at all seasons.
IV. THORN LESS TRI FOLIATES
Remarks; Fruits eaten by ruffed jjrouse and wild turkey. Twigs browsed bv whitetail deer.
CISSlTS (Missus incisa (Nutt.) Des Moulins Not ill us.
Recognition: A stout, sometimes evergreen climbing vine with deeply 3-lobed or 3-parted thick leaves, Tendrils (see grapes, Plate 34) that do not have disks at the tips, occur opposite most leaf scars, Even when bearing 3-lobed leaves, it is distinct from the true grapes in that the bark is tight rather than shreddy and the pith is white, not brown, Foison-ivv climbs by aerial rootlets. Pound primarily in sandy and rocky areas; se. Kansas and Missouri to Texas and Florida.
HOPTREE Ptelea trifoliata L, p. 154
Recognition: An upright shrub or small tree with 3-parted haves that usually are hairless but may be hairy beneath. Leaflets usually with out teeth, end leaflet short-stalked. Twigs brownish and round; buds hairy and hidden in summer by leafstalk; leaf sears U-shaped; bundle scars 3. End buds false. Trunk bark rather smooth, light colored, shallowly grooved. Var, moUis T. & G., occurring only on Lake Michigan sand dunes, has velvety twigs and leaves. Leaves 4"-10". Height 10-20' (25'); diameter 2"-10" (Ifi"). Flowers greenish, small, clustered. May-July. Fruits flat, circular, papery, 2-seeded, Sept,-spring. Similar species; (1) Often mistaken for Poison-ivy (p. 130). (2) See Fragrant Sumac (p. 131).
SCOTCH BROOM Cytisus scoparius (L.) Link p. 154
Recognition: A dense stiff-branched, hairless, evergreen shrub. Leaves small, some not divided, but trifoliate compound leaves most abundant. Twigs slender, angular, grooved, greenish, often withered at tips. Leaf scars round; bundle scars single. Buds small but visible, flanked by slender stipules. Leaves W-l'\ Height to 10". Flowers large, yellow, May-June. Fruits pods, long, July-Sept
Similar species: Small leaves and green ridged twigs of this European importation are unique among thornless woody tri-foliates except for (1) Bicolor Lespedeza, which is less bushy, not evergreen, and has smaller fruits, (2) Matrimony-vines (Plate 37) usually thorny and twigs not green, (3) Shrubby Cinquefoil (Plate 30) lower and has 5-parted leaves, (4) See also Gorse (Plate 6),
RICOLOR LESPEDEZA Lespedeza bicolor Turez. Not illus. Recognition: In many places this slender and weak shrub is planted as food for the bobwhite quail. Although not reported as spreading, it may be encountered under conditions appearing to be wild. Usually grows in patches or stands.
Leaves shaped like those of Scotch Broom hut all leaves are 3-parted, Leaflets blunt-tipped, with midrib usually extending slightly beyond leaflet tip, Twigs very slender, brownish or greenish, with 8-12 fine lines and grooves running lengthwise. Buds very small, flanked by slender stipules. Weak stems mostly end in upright cluster of purplish flowers or small dry fruit pods
W-V4". Leaves l"-3'\ Height 4'-6' (10')- Fields; north to New York, Michigan, and Minnesota.
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