with claws, stamens six; pod oblong to linear, one to two inches long, the stipe as long as the pedicel; seeds reniform, embryo coiled. From Iowa and Minnesota to the Rocky Mountains, New Mexico, Arizona, and Manitoba. Rose Family (Rosaceae).-Herbs, shrubs or trees, leaves regular, flowers alternate or some opposite; stamens generally numerous, stipulate frequently falling soon after the leaves appear,

distinct, inserted on the calyx;

petals as many as the sepals or rarely wanting; pistils one to many, generally distinct, except in Pomeæ, where the pistil is united to the calyx; fruit various; achenes, follicles, drupes, or pomes, as in the apple; seeds one to many, without albumen; embryo straight, with large cotyledons. The order contains about 90 genera and 1,500 species of wide distribution; in temperate and tropical regions, some boreal. But few of the plants are noxious or have noxious qualities.

Fig. 118. Stinkweed (Cleome

Common Five-finger (Poten- serrulata). (Ada Hayden). tilla monspeliensis, L.).—A stout, erect biennial, one-half to two feet high, with ternate leaves, obovate or oblonglanceolate leaflets; flowers yellow, in cymose clusters; calyx flat, deeply five-cleft, with as many bracts intervening; petals five, roundish; seed small, yellowish, longitudinally furrowed, sometimes reflexed. Probably introduced from Europe, though it may have been indigenous. It is now found growing in dry or wet soil from New England to the Rocky Mountains and Utah.

Showy Cinquefoil (Potentilla fruticosa, L.).-A woody perennial with an erect, shrubby stem from one to four feet high; pinnate leaves of five to seven leaflets; yellow flowers. It is cultivated as an ornamental plant, but becomes weedy in some parts of the East, especially in Vermont, where Prof. L. R. Jones says it "is the most

aggressive weed invader known, taking almost complete possession of the pastures and even pushing into tilled lands." It has a great abundance of seeds, which are scattered by the wind as freely as are dandelion seeds. The plant also sprouts freely from the crown when that has been cut back.

Silver Weed (Potentilla Anserina, L.). An herbaceous perennial, growing in marshes and wet grounds; leaves all radical, pinnately-compound; leaflets seven to twenty-one, with smaller ones interposed, oblong, sharply serrate, silky underneath; bractlets Fig. 119. Five-finger and stipules present, both some(Potentilla monspeliensis). times cleft incisely; flowers soli(Ada Hayden). tary, yellow, petals five, calyx five-cleft, the bractlets arranged alternately with the sepals, thus giving the appearance of a ten-cleft calyx; stamens many. This weed spreads by means of its slender, jointed runners, much in the same way that the strawberry does.

White Avens (Geum canadense, Jacq.).—A smoothish or often pubescent perennial, slender stem two feet or more high; root leaves with three to five leaflets, the terminal one broadly ovate or obovate; stem leaves threedivided or lobed, calyx bell-shaped or deeply cleft,

stamens many, fruit densely, bristly hirsute. In shady places, especially woods, but sometimes in open fields from Nova Scotia to Georgia, west to Kansas, Missouri, Minnesota and Wisconsin, often troublesome.

Prairie Rose (Rosa arkansana, Porter).-A low shrub with prickly stem; stipules narrow, more or less glandular toothed; leaves compound; leaflets seven to eleven, broadly elliptical to oblong-lanceolate; flowers in corymbose clusters, sepals occasionally hispid. Common on the plains in Minnesota, Iowa, and westward to Colorado. Often a very troublesome weed.

Rosa Woodsii, stem with slender or recurved spines and scattered prickles or smooth; leaves with rather broad stipules, entire; fruit globose or globose-ovoid. Colorado, Utah, and the Rocky Mountain country.

The Rosa Sayii, also western, grows from one to two feet high, very prickly; stipules usually dilated, glandular and resinous; flowers usually solitary. From Minnesota to Colorado and westward.

Black Raspberry (Rubus occidentalis, L.).-This becomes a troublesome plant in northern parts of the country. The prickly stems inflict annoying scratches.

Wild Red Raspberry (Rubus idaeus, var. aculeatissimus, (C. A. Mey.) R. and T.).—This plant is often abundant in fields of the North; it may be recognized by its hairy and prickly stems. Often troublesome in the North.

Dewberry (Rubus villosus, Ait.).-This plant grows in dry, open places in northern and western parts of the country. Often troublesome.

Pulse Family (Leguminosae).-Herbs, shrubs, trees or vines with alternate, mostly compound, stipulate leaves, papilionaceous or sometimes regular flowers; calyx three to six or four to five-cleft; stamens ten, rarely five, and sometimes many, monadelphous, diadelphous or distinct; pistil, simple, free, becoming a legume in fruit or sometimes a loment; ovules one to many; seeds generally ex

albuminous, or nearly so, or, in some cases, with copious albumen. About 6,500 species of wide distribution, but most abundant in the tropics.

Partridge Pea (Cassia Chamaecrista, L.).—An annual herb with simply and abruptly pinnate leaves; spreading stems; leaflets ten to fifteen pairs, linear-oblong; flowers large, yellow, often with a purple spot at the base; anthers ten, unequal; style slender. Sandy fields, common in the Mississippi Valley and south to Texas.

C. nictitans is like the above, but smaller, the wild senna (C. marilandica), grows from three to four feet high; has deciduous stipules; large leaflets; petiole with a large club-shaped gland near the base. Plant perennial. Common from southern Iowa to Illinois, southeast Nebraska and southward to Texas.

C. Tora is an annual; leaflets three, or (rarely) two pairs, obovate, obtuse, with an elongated gland; pods slender, curved. Common southward.

C. occidentalis, L. is an annual with four to six pairs of ovate-lanceolate leaflets; pods long, linear. Common southward to Texas and Arkansas.

Rattle Box (Crotalaria sagittalis, L.).—A hairy annual from three inches to one foot high, and having a small tap-root; stem villous and wing-margined; leaves, oval or oblong-lanceolate, from one-third to one-half inch wide, the edge of the leaf being hairy and entire, or somewhat wavy; stipules united and lying back on the stem, becoming inversely arrow-shaped; each peduncle produces a few yellow flowers about one-fourth inch in diameter; calyx five-cleft; standard of the corolla large and heartshaped, keel scythe shaped; stamens monadelphous, the anthers of two sizes, five being smaller than the other; the large, inflated pod bears, at first, some resemblance to the garden pea, being greenish in color, but later turns dark and varies in size from three-fourths to one inch in diameter; seeds very small and when mature, breaking

away from point of attachment, rattling in the pod, hence the name of the plant. Common in sandy soil, and found in large numbers on the sand bars of the Missouri River, where it may be collected by the wagon load. This plant, in Iowa, is one of the chief causes of "loco disease," and is generally regarded as poisonous.

White Sweet Clover (Melilotus alba, Desv.).—An erect annual or biennial, growing from three to four feet high; leaves compound, small white flowers, growing on rather slender flower stalks; seeds small, yellowish brown in color and with a peculiar cumarin-like odor, which also characterizes the leaves and stem. An introduced plant found throughout the northern Mississippi valley, and especially abundant along roadsides, in meadows, in fields. of corn and wheat, and along the railways; spreads by means of seeds and is an annual, biennial or short-lived perennial. Sometimes used as a forage and honey plant. It has a high percentage of protein. When the plant Fig. 120. Yellow is abundant in grain fields, flour ground lotus officinale). sweet clover (Melifrom this grain has an unpleasant odor. Hay containing it is disagreeable to stock, cattle refusing to eat it at first. There are indications also that the plant is somewhat poisonous. The yellow-flowered sweet clover (M. officinalis) is troublesome and common in the West.

Low Hop-clover (Trifolium procumbens, L.).—An annual with slender and procumbent, or ascending, pubescent stems, three to six inches high; leaflets wedge-obovate, notched; stipules ovate, short; flowers yellow, short pedicels reflexed with age. Eastward in the eastern states, and west of the Rocky