Stick-Seed. Burr Seed. Lappula echinata Gilibert. Lappula Lappula (L.) Karst. Flowers blue, ovary deeply 4-lobed separating into four warty achenes, each one brown, about 2.5 mm. long, slightly flattened, ovate with wedge-shaped apex; the upper side bearing a few stiff straight, diverging cap-shaped hairs, bearded on all sides; lower side destitute of hairs, bearing a straight ridge from the point to the middle of the large end. Introduced from Europe. Very objectionable in pastures.

Wild Comfrey. Lappula Virginiana (L.) Greene. Flowers blue; ovary deeply 4-lobed separating into four brown achenes, about 3 mm. long, flattened on upper side, broadly ovate, the apex wedge-shaped, the upper side clothed with stiff straight cap-shaped hairs, bearded on all sides; lower side a low 4-sided cone, nearly smooth with a concave triangular scar. Native to rich woodlands.

Red Root. Wheat Thief. Corn Gromwell. Lithospermum arvense L. Flowers white; ovary 4-divided separating into four hard, conical-ovoid achenes, each dull gray, erect, wrinkled, 2.5–3 mm. long, convex on the back, keeled on the inner side, base obliquely truncate, containing two minute white tubercles. A prominent weed of high rank in fields of winter wheat.

VERVAIN FAMILY. VERBENACEAE.

Blue Vervain. Verbena hastata L. Achenes crowded, four together until mature, dull, reddish brown, flattened, oblong, 1.7–2 mm. long, bordered by a narrow margin, the outer face convex, bearing 3–5 small vertical ridges branching and uniting at the apex, forming a distinct network, the inner face sloping to the margin from a central vertical ridge; a light colored scar is seen on one side of the base. Native to this country. Not important.

Nettle-leaved Vervain. Verbena urticifolia L. Achenes 1.6–1.8 mm. long, very closely resembling the last above mentioned. The achenes of this one are a trifle shorter and broader, more nearly oval than oblong. Native to this country. Not common in fields.

MINT FAMILY. LABIATAE.

Dead Nettle. Lamium amplexicaule L. Achenes light brown, conspicuously marked by white spots some of which coalesce making the surface striped crosswise, obovate-oblong, pointed at the smaller end, 1.5–2 mm. long, the outer surface rounded, the inner face angled, the concave surfaces sloping to the edges from a central vertical ridge. Introduced from Europe. Thrives in cool weather.

Motherwort. Leonurus Cardiaca L. Achenes light brown, obovoid-oblong, rounded on one side flat on the other two sides, the truncate apex hairy, 2–2.4 mm. long. Introduced from Europe. Waste places.

White Hoarhound. Marubium vulgare L. Achenes dull, varying from light to dark brown, sometimes finely roughened by numerous minute tubercles, slightly flattened, oval or obovoid, about 2 mm. long, outer surface convex, inner face angled sloping to the edges from a central vertical ridge, edges of achenes often slightly margined, surface lightly grooved. Introduced from Europe. A weed in northern Michigan where snow protects it in winter.

Catnip. Catmint. Nepeta Cataria L. Achenes dull, light reddish brown to nearly black, with two laterally placed cavities near the base, each filled with white spongey tissue, broadly oval, slightly flattened, 1.3–1.7 mm. long. Introduced from Europe. Scarcely a weed.

Self-heal. Heal-all. Prunella vulgaris L. Achenes light to dark brown, slightly roughened, having a diffused luster, slightly flattened, oval or oblong, the base tapering to a small whitish, triangular appendage, outer side convex having dark verticle lines, the other face sloping to the edges from a central ridge, becoming mucilaginous when soaked in water. Native to this country.

NIGHT SHADE FAMILY. SOLANACEAE.

Jimson Weed. Thorn-apple. Datura Stramonium L. Pods ovoid, densely prickly, about 4 cm. long; seeds black to brown, flattened, with 6–10 slight irregular elevations, the whole surface covered with minute shallow pits, short kidney shaped, i. e., one edge nearly straight or slightly notched, the remainder of the margin making about two-thirds of a circle. 3–3.5 mm. long. Most likely introduced from Asia. A coarse, poisonous weed found in waste places.

Purple Jimson Weed. Purple Thorn-apple. Datura Tatula. The color of the stems are purple, the flowers and pods nearly the same as those last above; seeds of the two scarcely if at all unlike. Naturalized from tropical America. Waste places.

Horse Nettle. Solanum Carolinense L. Berry orange-yellow, 1.6 to 2 cm. in diameter; seeds lemon yellow, slightly double convex, obovate 2.1–2.9 mm. long, surface finely granular all over. Native of the southwest U. S. It spreads rapidly by long roots.

Black Nightshade. Solanum nigrum L. Berry black, smooth, globose, 8–10 mm. in diameter; seeds finely granular, dull, yellowish to light brown, flattened, unsymmetrically ovate, about 1.5 mm. long. Native to this country. I have the best of authority for saying that these berries when ripe make good pies, whether the uncooked fruit is poisonous there is less proof. Of little importance.

Beaked Nightshade. Solanum rostratum Dunal. Fruit surrounded by a persistent prickly calyx about 2 cm. long; seeds flattened, irregularly undulate or wrinkled, dark brown or black, usually ovate or circular in outline, 2–2.5 mm. in diameter, surface covered with small pits. Introduced into Michigan from the southwest. A coarse prickly weed.

FIGWORT FAMILY. SCROPHULARIACEAE.

Butter and Eggs. Toad-Flax. Linaria vulgaris Hill. Linaria Linaria (L.) Karst. Flowers yellow and orange; seeds dark brown or black, flat, circular or oval, surrounded by a broad wing-margin, the wing notched and covered by numerous fine radiating ridges, the surface of the seed roughened by numerous projecting points, seed, including its wing, 1.5–2 mm. long. Introduced from Europe. A vigorous weed in meadows, spreading by seeds and by root stocks.

Moth Mullein. Verbascum Blattaria L. Flowers yellow; pod 6 mm. diameter; seeds light to dark brown, .5–1 mm. long, columnar, lateral surface slightly angular and 6-sided, base truncate or obliquely so and broader than the rounded apex, thus somewhat thimble-shaped, each lateral face deeply pitted in longitudinal rows, the pits in contiguous rows, alternating. Introduced from Europe. A vile weed in meadows and pastures.

Velvet-Leaved Mullein. Verbascum Thapsus L. Flowers yellow; pod 6 mm. high; seeds cannot be distinguished with certainty by means of the ordinary lens from those of moth mullein. The pitted surface seems to predominate in Verbascum Blattaria, while the grooved surface seems to be more common in the seeds of V. Thapsus. Introduced from Europe. Common in thin pastures.

Wall Speedwell. Veronica arvensis L. Pods heart-shaped; seeds dull, light yellow, flattened, oval, .7–1.1 mm. long on one side appearing as though the two ends had been brought together by bending. From Europe.

Common Speedwell. Veronica officinalis L. Pods heart-shaped; seeds dull, pale yellow, flattened, broadly oval to broadly obovate, .8–1.2 mm. long, with a small scar near the middle of one side, from which extends a faint line (raphe) to one extremity. Appearing as though introduced.

Purslane Speedwell. Veronica peregrina L. Pods heart-shaped; seeds dull, light reddish yellow, flattened, oval to broadly obovate .5-.8 mm. long, with a small scar a little above the middle of one side, from which extends a dark line (raphe) to one extremity. Most likely native to this country.

Thyme-leaved Speedwell. Veronica serpyllifolia L. Pods broadly heart-shaped; seeds pale yellow, a trifle darker than those of V. officinalis, light, reddish yellow, in shape and markings much like those of V. peregrina, flattened, broadly oval to obovate .5-.7 mm. long, with a small scar near the middle on one side, from which extends a dark line (raphe) to one extremity.

Apparently native to this country.

Seeds of the Veronicas are very difficult to distinguish from one another.

PLANTAIN FAMILY. PLANTAGINACEAE.

Sand Plantain. Plantago arenaria W. & K. Seeds dark amber brown, shining, rounded on the back like the bottom of a shallow canoe, 2.5–3 mm. long, transverse groove around the middle of the back, opposite side with a groove extending lengthwise, about as wide as the ridge on either side of it; hilum in the middle of the groove. Found at Harrisville, Mich.

Large-bracted Plantain. Plantago aristata Michx. Seeds oval, dull, light to dark brown, 2.2–3 mm. long, shaped like a shallow, thick-walled canoe with ends rounded alike, outer face marked by a shallow, transverse groove at or near the middle, a white line marking the margin at the base on the canoe inside, two white-margined pits occupying the middle of the concave side. Introduced from the west in clover seeds, not yet common.

Rib-Grass. Narrow-leaved Plantain. Plantago lanceolata L. Seeds shining, amber-colored to brown, oval, 2–2.5 mm. long, shaped like a shallow, thick-walled canoe with ends rounded alike, a dark scar occupying the middle of the narrow concave side, a faint, transverse groove across the convex side near the middle sometimes apparent. Often found mixed with clover seeds from which it is very difficult to separate. Introduced from Europe.

Broad-leaved Plantain. Plantago major L. Seeds, light to dark brown or very nearly black, 1–1.5 mm. long, slightly flattened, with acute edges very variable in shape, oval, oblong, rhomboidal and trapezoid, the surface roughened by slender, colored ridges, appearing under the lens as slightly wavy lines, radiating from the scar. The clear light green color of the lower end of the leaf-stem is an easy mark to distinguish this plant from another broad-leaved plantain, P. Rugelii in which the base of leaf is red. Introduced from Europe. About door yards.

Rugel's Broad-leaved Plantain. Plantago Rugelii Decne. Seeds dark brown to black, much like those of P. major, but larger, 1.5–2.5 mm. long slightly flattened, with edges acute, very variable in shape, oval oblong, rhomboidal, surface minutely roughened and dull, but wholly without ridge or lines as in P. major. Native of this country. Lower end of leaf-stalk red, and not clear green as in P. major. A vile pest in clover fields.

MADDER FAMILY.

Blue Field Madder. Sherardia arvensis L. The parts often called seeds are in reality the half-fruits ripened, each one bearing at the apex three, white, pointed, persistent calyx lobes, the inner face showing a vertical groove, and in some of the fruits the calyx is broken off. Surface dull brown, clothed with small white hairs, obovoid, 2–2.5 mm. long. Introduced from Europe, not often found in the northern states.

TEASEL FAMILY. DIPSACACEAE.

Wild Teasel. Dipsacus sylvestris Huds. Achene brown, minutely hairy, 4 mm. long, oblong, square in cross-section, with four vertical ribs on the angles and four on the sides. Seed suspended, anatropous, supplied with endosperm. Introduced from Europe. A weed requiring two years from seed to seeding.

COMPOSITE FAMILY. COMPOSITAE.

Yarrow. Milfoil. Achillea Millefolium L. Flowers white; achenes white to gray, finely striate lengthwise, flattened, oblong, tapering at the lower end, straight or curved. 2–2.3 long. Most likely introduced from Europe.

Ragweed. Ambrosia artemisiifolia L. Achenes hard, straw-colored to light brown or black, top-shaped, broadly oval, 2.5–3 mm. long, besides the beak 1.5 mm. long, the sides irregularly ridged vertically, with 5–10 short teeth at the apex. Sometimes the hard covering is removed by a clover huller, exposing the naked seed. Native of the U. S.

Great Ragweed. Ambrosia trifida L. Achenes hard, brown, more or less mottled, top-shaped, 7–8 mm. besides the stout beak 2–3 mm. long, sides with 5 stout ridges terminating in 5 short teeth. Native to the United States. River bottoms, low land, sometimes 15 ft. high.

Corn Camomile. Anthemis arvensis L. Achenes very variable, creamy white to light brown, oblong, wedge-shaped in outline, circular to four-angled in cross-section, more or less ribbed lengthwise, a ripple-shaped scar at the narrow end; apex truncate with a minute projection in the center, often with a narrow ridge about the margin. About 1.7 mm. long. Introduced from Europe. Seldom troublesome in Michigan.

May-weed. Dog's-Fennel. Anthemis Cotula L. Outer flowers white; achenes straw color to light brown, obovoid (large end uppermost) to oblong, circular in outline, 1.3–1.8 mm. long, with 10 warty ribs. Introduced from Europe. Old roads and waste places.

Great Burdock. Arctium Lappa. So far as I have seen the achenes of this species, when compared with A. minus, are darker colored, rather longer, the ribs more distinct.

Smaller Burdock. Arctium minus Beruh. Possibly only a variety of A. Lappa L., but the prevailing plant in central Michigan. I see no way of distinguishing the achenes of one from the other; but it makes little difference as one burdock is as bad as another.

Flowers purple; achenes dull brown, often spotted with black, straight or curved, slightly flattened, oblong-prismatic with 3–5 narrowly ridged angles, and occasionally other smaller ridges, 4.5–6 mm. long. Introduced from Europe.

Biennial Wormwood. Artemisia biennis Willd. Achenes dark brown, smooth, somewhat flattened, 3–4 angled, obovate, narrowed at the base .8–1.3 mm. long. Native in the northwestern United States and introduced east with grass seeds. Moist land.

Smaller Bur-Marigold. Bidens cernua L. Flowers yellow; achenes 4–6 mm. long, dull brown, the awns lighter, flattened, 4-angled, wedge-shaped, awns 2–4, barbed downward as also are the ribs. Native of this country. Low lands.

Purple-stemmed Swamp Beggar-ticks. Bidens connata Muhl. Flowers orange; achenes brown, wedge-shaped or obovate, hairy, tubercled, flattened, 4-angled, 4-toothed, 4–6 mm. long, achenes and teeth downwardly barbed. Swamps, common.

Beggar-ticks. Bidens frondosa L. Achenes dull brown, tubercled, much flattened, obovate or oval, 6–12 mm. long, awns usually 2, spreading barbed downward. Low lands.

Star Thistle. Centaurea solstitialis L. Achene cream white to mottled brown, flattened, oval about 2 mm. long; scar of attachment in a notch of one edge above the rounded base, apex truncate with a small tubercle in the middle. Found in seeds of alfalfa. A ragged plant from Europe.

Ox-eye Daisy. Chrysanthemum Leucanthemum L. Flowers white; achenes brown or black with ten white conspicuous vertical ribs, narrowly obovate 1.5–1.8 mm. long, bearing a tubercle at the apex. Introduced from Europe. Becoming common. A prominent weed in old pastures and meadows.

Chickory. Chichorium Intybus L. Flowers yellow; achenes light brown, more or less mottled or spotted with black, straight or curved, 4–5 angled, flattened, apex truncate crowned with a double row of minute scales. Achenes 2.5–3 mm. long. Introduced from Europe.

Canada Thistle. Cirsium arvense (L.) Scop. Carduus arvensis (L.) Robs. Flowers purple or white; achenes smooth, light brown, curved or straight, narrowly obovoid or oblong, slightly flattened, 2–3 mm. long, apex truncate, cup-shaped with a tubercle in the center. Introduced from Europe. A weed of first rank.

Bull Thistle. Cirsium lanceolatum (L.) Hill. Carduus lanceolatus L. Flowers purple; achenes smooth, nearly white, with sharp vertical brown stripes, slightly flattened, obovate or oblong, usually curved near the apex, 3–4 mm. long, apex truncate with a large tubercle in the center. Introduced from Europe.

Narrow leaved Hawksbeard. Crepis tectorum L. Flowers yellow; achene chestnut brown, straight or curved, linear, ribs 10, smooth or rugose; 3.4 mm. long. Introduced from Europe.

Fire-weed. Erechtites hieracifolia (L.) Raf. Achenes brown, linear, 2.2–2.8 mm. long, flattened, straight or curved, having ten vertical ribs between which are minute white oppressed hairs, the extremities truncate, wider than the narrow portion beneath, the apex white with a tubercle projecting from the center of a minute cup. Native to this country. Not of much importance.

Annual Fleabane. Erigeron annuus (L.) Pers. Flowers white; achenes smooth, shining, brownish white, translucent, flattened, obovate or oblong, .7-.9 mm. long, bearing at the apex a whorl of very small diverging bristles, the longest ones having been rubbed off. Faint traces of a few oppressed hairs may be seen under a good lens. Native to this country and a very prominent weed in thin meadows.

Horse-weed. Erigeron Canadensis L. Leptilon Canadense (L.) Britton. Achenes oblong, dull cream color, much flattened, 1–1.3 mm. long, shining, smooth or containing a few minute oppressed bristles, apex truncate, bearing a whorl of bristles, the longest having been rubbed off. Native of this country. Compare the above description with that of Erigeron annuus. Common in waste places.

Daisy Fleabane. Erigeron ramosus (Walt.) B. S. P. Flowers white; achenes nearly identical with those last described, Erigeron annuus, bristles shorter, less diverging, surface bearing more minute appressed hairs when seen under a lens. Native to this country and prominent in some thin meadows.

Sweet Everlasting. Gnaphalium polycephalum Michx. Gnaphalium obtusifolium L. Outer scales of the head thin, white, stiff; achenes yellowish white or brown, slightly flattened, smooth, oval or oblong, .5-.7 mm. long. Native to this country. Not often troublesome.

Much practice with a good lens and careful comparisons with other small achenes will be necessary in identifying such specimens as are furnished by this species.

Low Cudweed. Gnaphalium uliginosum L. Outer scales of the head thin, brown, more or less wooly; achenes .4-.6 mm. long, yellowish white to brown, slightly flattened, smooth, narrowly oblong .4-.6 mm. long. Achenes narrower and rather shorter than those of G. obtusifolium. Native to this country. Not of high rank as a weed.

Broad-leaved Gum Plant. Grindelia squarrosa (Pursh.) Dunal. Flowers yellow; achenes creamy white or light brown, very variable in appearance, more or less flattened, often 4-angled, straight to much curved, narrowed at the base, apex truncate, often concave with a distinct marginal rim, some of them not very unlike those of Canada thistle, some of them smooth, others finely grooved or ridged lengthwise, others somewhat wrinkled, 2.5–3 mm. long. Occasionally introduced from the west with seeds of grasses or clover. Usually not persistent in Michigan.

Artichoke. Helianthus tuberosus L. Flowers yellow; achenes black, shiny more or less, slightly flattened, pubescent with very short hairs, with four obtuse angles, narrowly obovate, 6–7 mm. long, one side of the smaller end projecting beyond the other side. Native of this country; cultivated by Indians.

Golden Mouse or Orange-Ear Hawkweed. Devil's Paint-Brush. Hieracium aurantiacum. Flowers orange yellow; achenes jet black, oblong, straight or curved, apex truncate, base abruptly tapering, cylindrical, the sides bearing 10 narrow, vertical ridges. Introduced from Europe. In Eastern New York and Western Massachusetts meadows abound in large areas of this vile weed, 1.8–2.2 mm. long.

Mouse-Ear Hawkweed. Hieracium Pilosella L. Flowers yellow; achenes jet black, oblong, straight or curved, apex truncate, base abruptly pointed, cylindrical or narrowly oval, the sides bearing 10 narrow vertical ridges. Introduced from Europe. The achenes very closely resemble those of the orange hawkweed. It doesn't matter much, for the habits are the same, and one is about as noxious as the other. Introduced from Europe.

Elecampane. Inula Helenium L. Flowers yellow; achenes light brown, straight or curved, linear, flattened, 4–5 mm. long, 4 sided with 5–8 obscure vertical ridges on each side, apex concave, the margin bearing a circle of short stiff bristles, the remains of longer ones. Introduced from Europe. Not common.

Marsh Elder. Iva xanthiifolia (Fresen.) Nutt. Achenes various shades of brown to black, flattened or rhombic in section, obovoid, 1.5–2 mm. long, longitudinally, striate with fine lines. Native to the upper peninsula of Michigan where it most likely was at one time introduced from the west. It has not been found in the lower peninsula, probably because it had no means of coming across Lake Michigan.

Wild Lettuce. Lactuca Canadensis L. Flowers yellow; achenes black or nearly so, flattened, oval, bearing 3 ribs, the lateral ones sometimes double, the middle one slender, surface abounding in minute transverse ridges as seen under a lens, the remains of a beak sometimes remaining. Native of this country. Other species of Lettuce are more or less troublesome.

Prickly Lettuce. Lactuca virosa L. For many years erroneously called Lactuca scariola. Flowers yellow; achenes dull, dark brown, mottled with black, flattened, bearing 5–7 rough, vertical ridges, interspersed by as many smaller ones; oblong, obovate, widest toward the tapering apex. 3–3.5 mm. long. Some of the leaves turn one edge up and the other down. Introduced from Europe and has proved itself a remarkable traveller.

Fall Dandelion. Leontodon autumnalis L. Flowers yellow; achenes light brown, linear, with 5 broad, rounded ribs; achene 4–6.5 mm. long, straight or curved, the outer traversed, with low transverse ridges. Introduced from Europe.

Black-eyed Susan. Yellow Daisy. Rudbeckia hirta L. Achene purple-brown to black, slightly tapering from base to apex 1.5–1.8 mm. long, base abruptly pointed, apex truncate, in cross section nearly square, having 5–7 slender vertical ridges on each side besides a larger one at each of the four corners. Widely distributed in meadows and pastures.

Corn Sow-Thistles. Sonchus arvensis L. Flowers yellow; achenes dull, dark reddish brown, oblong, extremities blunt, slightly flattened, bearing four coarse, fold-like ridges, with two smaller ridges between each of the two large ones, transversely wrinkled, 2.5–3 mm. long. This species is a perennial spreading by roots-stalks as well as by seeds. Introduced in Europe.

Spiny Sow-Thistle. Sonchus asper (L.) Hill. Flowers pale yellow; achenes dull straw-color to reddish brown, much flattened, obovate, oblong, extremities blunt, each side bearing 3–5 vertical ridges, surface nearly smooth, 2.5–3 mm. long. Introduced from Europe.

Common Sow-Thistle. Sonchus oleraceus L. Flowers pale yellow; achenes reddish brown, linear, oblanceolate, 3 mm. long, flattened extremities blunt, 5 uneven wrinkled ridges on each side. Introduced from Europe.

Red-Seeded Dandelion. Taraxacum erythrospermum Andrz. Achene bright red or red reddish brown, flattened, oblanceolate, 3 mm. long, 1 mm. wide or less, the red beak 1 mm. long, prickles often extending nearly to the base along twelve vertical ribs, the achenes narrower, shorter, much darker in color, with prickles extending farther down the ribs, the short beak longer; the plant is earlier, often smaller, when compared with the other species.

Doubtless this is more common than has been reported, having been overlooked. Introduced from Europe.