PULSE FAMILY. LEGUMINOSAE.

Fig 106. [Ax Seed. Ax Wort. Coronilla scoparioides] Koch.

Ax Seed. Ax Wort. Coronilla scoparioides Koch. Seed reddish brown, oblong, slightly flattened and curved, 4–5 mm. long, 1.5 mm. wide, with a circular scar in a depression on the middle of one edge, and a slight ridge the entire length of both sides. Introduced from Europe, not yet a prominent weed in Michigan.

Fig 107. [Bird's-foot Trefoil. Ground Honeysuckle. Bloom-fell. Lotus corniculatus] L.

Bird's-foot Trefoil. Ground Honeysuckle. Bloom-fell. Lotus corniculatus L. Seed light brown occasionally mottled with black, shining, spherical to ovoid, slightly compressed near one edge, 1–1.2 mm. in diameter, the compressed portion (raphe) extending half to three-fourths the length of the seed to the hilum or scar, above this the seed is narrower. Introduced from Europe. Seldom met with in this country.

Fig 108. [Black Medick. Nonesuch. Medicago lupulina] L.

Black Medick. Nonesuch. Medicago lupulina L. Flowers light yellow; pods black, oval, much flattened, spirally coiled, causing the two extremities to nearly meet; 2–2.8 mm. long; seeds smooth, dull yellow to green, oval, flattened, kidney-shaped, with a tubercle near the middle of the concave edge or like the figure, 1.5–1.8 mm. long. Introduced from Europe and becoming frequent in grass land. Its worst feature is to supply seeds that may be mistaken for and mixed with seeds of alfalfa and red clover. The seeds differ from those of alfalfa in being more commonly egg-shaped than kidney-shaped in outline. The scar is nearer the small extremity in these seeds than in those of alfalfa. For pasture this is less valuable than white clover.

Fig 109. [Alfalfa. Lucerne. Medicago sativa] L.

Alfalfa. Lucerne. Medicago sativa L. Seeds varying much in shape and size owing to their crowding in the pod when young, yellowish green to light brown. The cuts give a good idea of the variety of shapes; surface dull or somewhat glossy, often kidney shaped, with the scar in a depression near the middle, the tips may be truncate or acute or rounded, 2–2.5 mm. long in cross-section, oval; when viewed from one edge it is seen to be bent or warped in various ways, half anatropous, often seen with a slight depression extending along one edge from the scar to one end, larger seeds more often flattened than are the shorter. A prominent forage plant, the seeds of which are often adulterated. Native of Europe.

Fig 110. [White Sweet Clover. Melilotus alba Desv.]

White Sweet Clover. Melilotus alba Desv. Flowers white; pods straw-color to brown, coarsely and irregularly reticulate-ridged or wrinkled; seeds smooth, dull, yellowish or greenish, more strictly elliptical-oblong in outline than those of red clover and alfalfa, bearing the broad, shallow notch near one extremity; 2–2.2 mm. long. Introduced from Europe. Seeds used to adulterate those of alfalfa.

Fig 111. [Alsike Clover. Trifolium hybridum] L.

Alsike Clover. Trifolium hybridum L. Seeds dull yellowish green to very dark green, some of them mottled, lighter about the seed scar, flattened, one of the rounded edges thicker than the other, and between the two a slight groove on each side; seed rounded at one end, the other truncate with the seed scar in the middle of the truncate end. Some seeds are half anatropous, resembling in shape those of red clover; 1.3–1.2 mm. in diameter. When compared with white clover, these seeds are larger and thicker. Introduced from Europe.

Fig 112. [Crimson Clover. Scarlet Clover. Trifolium incarnatum] L.

Crimson Clover. Scarlet Clover. Trifolium incarnatum L. Seed smooth, shining when not old, color light yellow to reddish yellow or brown, oval, scar about one-third the distance from the narrow end, three-fourths anatropous, 2–2.5 mm. long, very slightly compressed.

Fig 113. [Red Clover. Trifolium pratense] L.

Red Clover. Trifolium pratense L. Seeds usually dull, pure light yellow to purple, flattened, ovoid, having the seed scar near the middle of one edge or below the middle, half anatropous, a slight depression on each side from the scar toward the broad end, the short edge thinner than the long edge, 1.5–1.8 mm. long by 1.×1.4 mm. wide. Very common. Introduced from Europe.

Mammoth Clover is a variety or race or red clover, the seeds of which are indistinguishable from the seeds of red clover. As a rule they are darker in color and rather smaller. Red clover and mammoth clover are usually much mixed.

Fig 114.[Low Hop-clover. Trifolium procumbens] L.

Low Hop-clover. Trifolium procumbens L. A low, yellow-flowered annual, often becoming a tumble-weed at maturity. Seeds plump, shining, straw-colored to light brown, broad oval, very slightly flattened, 1 mm. long, three-fourths anatropous, i. e., the scar is a very little distance from one end of the seed. A little way back of the scar on each side is a light-colored depression. Rather rapidly spreading. From Europe.

Fig 115. [White Clover. Trifolium repens] L.

White Clover. Trifolium repens L. Seeds scarcely shining, yellow to light brown, flattened, one of the rounded edges thinner than the other, and between the two a slight groove on each side, one end rounded, the other truncate with a slight depression in the center containing the seed scar 1.-1.2 mm. long to 1 mm. wide. The seeds that are truncate at one end are anatropous, some of them resembling those of red clover are half anatropous. Common and well known, possibly native to the northern country.