There are sundry plants which are worthless and unsightly or offensive in agricultural grounds, and others which are especially injurious as intruders among cultivated crops. Such plants are regarded by all neat farmers in our country as nuisances to be abated, and are known by the distinctive appellation of weeds. In preparing such a list as that here contemplated, I propose to sketch very briefly, in a familiar style, the character of the nuisances referred to, and, with a view to economizing space, detailed botanical descriptions are omitted. The curious in such matters can readily acquire the knowledge of those details by consulting local and general floras. It is designed simply to arrange the plants herein enumerated, merely in accordance with the natural method, as employed by some of the most approved modern authors, as De Candolle, Hooker, Torry, Gray, &e., giving the authentic scientific names of the genera and species, so that all concerned can speak of them understandingly and intelligibly, and annexing the common or popular names in the vernacular, so far as the same are known or in use. With these aids and facilities, as clews to further researches, and accompanied with familiar remarks on their character, it is believed the weeds of our agriculture may become accurately known, and be disposed of, as they ought to be, by every intelligent and enterprising young farmer in the land.

Series I—Phaenogamous or Flowering Plants.—Class I—Exogenous Plants; outside growers. Sub-Class I—AngiospERMous Exogens; outside growers, with seed vessels.

Division I—Dipetalous Exogens; the petal mostly distinct.

1. Ranunculus bulbosus, (L.)—Buttercup, bulbous crowfoot, (p.) This foreigner is extensively naturalized in grass plots, meadows, and low ground pastures along our streams, where it is regarded as a nuisance by the farmers.
The fleshy bulb is highly acrid, and the plant when once introduced is difficult to subdue. The most effective remedy yet found is to get the plant closely depastured in early spring by stock, especially sheep.
Another perennial species, viz: Racris, (L.,) or tall crowfoot, is naturalized in New England, and is as obnoxious as its congener.

2. Delphinium consolida, (L.)—Field Larkspur, (a.) This introduced plant has strayed from the garden in many places, and is an unwelcome intruder in grain fields and other cultivated grounds. This and a kindred species (D. ajacis ) (L.) have become so common in gardens that some attention is requisite to prevent them from trespassing on the farms. Plants which have matured their seeds in the garden should never be carried to the barn yard, nor permitted to mingle with farm manures, otherwise the fields will be speedily infested with worthless and pernicious weeds.
A slight ploughing after the removal of the crops from the field will favor the germination of the seeds, which will be destroyed by the regular ploughing of the field.

3. Papaver dubium, (L.)—Field Poppy, (a.) This foreigner has found its way into some districts, and, if unattended to, may become a troublesome weed, as it and the “Corn Poppy,” P. rhoeas, (L.) are in Europe. A similar remark is applicable to the Prickly Mexican Poppy, Argemone mewicana, (L.,) another kindred weed which has been introduced. This plant should be extirpated by hand-weeding before the ripening of the seed. In Italy the prickly poppy became so obnoxious as to be called “infernal figs.”

4. Camelina sativa, (Crautz.)—Wild Flax, gold of pleasure, (a.) A naturalized foreigner, and, where neglected, becoming a great nuisance—formerly supposed by the simple and credulous to be a sort of transmuted or degenerate flax. It has been subdued by annual ploughing, so managed as to allow the seeds to vegetate, and thus destroy the young plants before the seeds on them are matured.

5. Capsella bursa pastoris, (Moench.)—Shepherd’s Purse, (a.) A worthless little intruder from Europe, but the valuable grasses will generally choke out such small weeds.

6. Raphanus raphanistrum, (L.)—Wild Radish, jointed charlock, (a.) A naturalized weed, becoming a nuisance in the northern States. It has already invaded New England and Pennsylvania, and is tending westward. The seeds are contained in a jointed pod, and are thus protected from the severity of frost and concealed from birds until liberated by the process of decay of the pod.

7.  Hypericum perforatum, (L.)—St. John’s Wort, (p.) A foreign weed, formerly supposed to cause cutaneous ulcers in white cows and on horses with white feet and noses; but, the disease disappearing, that notion seems to have become obsolete.

8. Agrostemma githago, (L.)—Cockle, rose campion, (b.) A well-known foreign weed infesting wheat fields. The black-coated seeds, when abundant and ground with wheat, are injurious to the appearance of the flour. The root of this plant should be cut below the surface with a chisel fastened to a long handle, and wielded by children. If this is neglected in the early part of the season, the fields should be scarified immediately after the removal of the crops, to favor the germination of the seed, and ultimate destruction by fall ploughing and the frost. The seed obtained from the screening of cereals should not be thrown out upon the manure heap, but fed to fowls, and the refuse left by them should be burned the next day.

9. Abutilon avicenne, (Gaertu.)—Indian Mallow, velvet leaf, (a.) This foreigner, hitherto regarded as a worthless and troublesome intruder in Indian corn fields, potato patches, and other cultivated lots, has been recently announced (together with Hibiscus moscheutos, (L.,) a malvaceous perennial, native of our maritime marshes,) as yielding a fibrous bark suitable for textile purposes, similar to the “Jute” of commerce, obtained from Asiatic species of corchorus, and employed in the manufacture of gunny bags. The economical value of this material, which is termed “American Jute,’ must be ascertained by experience.

10. Rhus vennata, (D. C.)—Poison Sumach, poison elder, (s.) A noxious shrub frequent in moist, low grounds, by which many persons are liable to be badly poisoned. A similar cutaneous affection is often produced by the climbing variety of another species—the Rhus toxicodendron, (L.,) Poison Vine or Oak.

11. Trifolium arvense, (L.)—Stone Clover, Welsh clover, rabbit-foot, (a.) This foreign plant is only entitled to notice on account of its worthlessness and prevalence in poor old fields. Its presence is a pretty sure indication of a thin soil and neglected agriculture, and the obvious remedy is to improve both.

12. Potentilla canadensis, (L.)—Cinquefoil, fivefinger, (p.) The varieties of this are rather harmless, though worthless native weeds, and are merely indications of a neglected soil. There is also a coarse, erect, homely, annual species, P. norvogica, (L.,) which is becoming a frequent weed in the middle States, and seems to have migrated from the North.

13. Rubus villosus, (Ait.,) Blackberry Bramble, common brier, (p.) Every one knows the common brier; the fruit in its season is a general favorite, and some remarkably fine varieties have been produced under careful culture. The tendency of the plant, however, to spread and take possession of neglected fields, causes it to be regarded as something of a nuisance where it prevails. Another and kindred species, the R. cuneifolius, (Pursh,) or Sand Blackberry, has found its way into Pennsylvania, apparently from New Jersey, and bids fair to establish itself in the land of Penn. Fence angles and waste places in which the briers have obtained a foothold should be cleaned of all weeds twice yearly, in spring and autumn. This will not only exterminate the briers, but admit air and light to the field borders, otherwise shaded.

14. Rubus canadensis, (L.,) Dewberry, running brier, (p.) Our American dewberry is a fine fruit, and generally preferred to all the blackberries proper, but it is not the dewberry of England, which is the Rubus caxius of Linneus. There is scarcely a farmer’s boy in Pennsylvania who is not well acquainted with our plant, from having encountered its prickly, trailing stems with his naked ankles while heedlessly traversing the old fields where it abounds. On well- managed farms, however, this and all other species of brier (not excepting our native raspberries) are becoming rare.

15. Rosa carolina, (L..) Swamp Rose, (p.) This is often an obnoxious plant in wet meadows and low grounds, forming unsightly thickets with other weeds if neglected. Another native species, R. lucida, (Ebrh.,) the Dwarf Wild Rose, is quite frequent in neglected grounds. The foreign Sweet Brier, Rosa Rubiginosa, (L.,) is naturalized in many localities and deemed a trespasser.

16. Sicyos angulatos, (L.,) One-seeded Star Cucumber. This climbing vine, with leaves resembling those of the cucumber, is a native weed, and a vile nuisance when admitted into gardens and cultivated lots.

17. Daucus carota, (L.,) Wild. carrot, (b.) When this wild variety-of the common garden carrot becomes thoroughly naturalized, as it is now on many farms in the middle States, it is a troublesome weed, and requires. persevering vigilance to get rid of it. It should be diligently eradicated before it ripens its seeds. In case of snow, with a smooth surface crust, the mature umbels break off and are driven by the winds to a great distance, and thus annoy an extensive district, Another umbelliferous nuisance is created by permitting the valuable garden parsnip, Pastinaca sativa, (L.,) to disseminate itself and multiply rapidly in adjoining fields, and along fence rows, giving to the farms a very slovenly appearance.

18. Archemora rigida, (D.C..) Cowbane, wild parsnip, (p.) This native weed occurs frequently in swampy meadows, and is reputed to be an active poison when eaten by horned cattle, which, however, probably seldom happens, unless the pasture is very deficient.

19. Ægopodium podagravia, (L.,) Goat Weed, (p.) A foreign weed, troublesome and difficult to eradicate.

20. Cicuta maculata, (L.,) Water Hemlock, spotted cowbane, musquash root, (p.). The root of this is poisonous, and proves fatal to children who collect and eat it by mistake for the root of sweet cicely, Osmorhiza longistylis, (D..C.) It is found indigenous along rivulets and margins of swamps, and should be carefully eradicated.

21. Conium maculatum, (L.,) Common or Poison Hemlock, (b.) A poisonous and dangerous weed, introduced from Europe, and occasionally met with about old settlements. It is supposed to be the identical herb with which the binge Greeks put their philosophers and statesmen to death when they got tired of them.

Division II.—Gamoreratous Exocens; Petals more or less united.

22. Sambucus canadensis, (L.,) Common Elderbush, (s.) This indigenous shrub is very tenacious of life, and inclined to spread extensively along fencerows and hedges, giving the premises a very slovenly appearance.

23. Dipsacus sylvestris, Mill Teasel, wild teasel, (b.) This coarse European weed is completely naturalized in some localities, and is not only worthless, but threatens to become a nuisance if not attended to.

24. Vernonia noveboracensis, Wild Iron Weed, (p.) A coarse native plant, quite common in moist, low meadow grounds, and along fence-rows. The root of this must be cut like the Canada thistle before the flowering season in spring, or the danger will be imminent of its over-running the whole area in a short period by means of its floating seeds.

25. Eupatorium purpureum, (L.,) Trumpet Weed, joe-pye weed, (p.) Several varieties of this tall, stout weed are indigenous on our moist low grounds.

26. Aster ericoides, (L.,) Heath-like Aster, (p.) Numerous species of this large American genus meet the eye of the farmer, in the latter part of summer, in his woodlands, low grounds, borders of thickets, &c., some of which are quite ornamental, but the little bushy one here mentioned is about the only one which invades our pastures to any material extent. In neglected old fields, it often becomes as abundant as it is always a worthless weed.

27. Erigeron canadense, (L.,) Horse, Weed, butter weed, (a.) This American weed has diffused itself all over our country, and, it is said, has reached and pervaded all Europe. The cultivation of hoed crops will clear the fields of this pest. Other varieties of the same genus infest meadows, which, if the evil becomes too burdensome, must be ploughed up.

28. Erigeron strigosum, (Muhl.,) Flea-bane Daisy, (a.) This very common native weed is apt to be abundant in the first crop of upland meadow, after the usual routine grain crop. After that, especially in good lands, it becomes more rare, being probably choked out, like many other weeds, by the valuable grasses.

29. Solidago nemoralis, (Ait.,) Golden Rod, (p.) Several species of golden rod occur along fence rows, borders of woods and thickets, and intrude upon neglected pasture fields.

30. Ambrosia trifida, (L.,) Great Rag Weed, (a.) A coarse, ugly native weed, common in waste places.

31. Ambrosia artemisia folia, (L.,) Bitter Weed, rag weed, (a.) This indigenous, bushy weed occurs in most cultivated grounds, and is most abundant among the stubble, after a crop of wheat. But if the land be good, the plant seems to be smothered or choked out the next season by the usual succeeding crop of clover and the grasses. It is always ready, however, to make its appearance whenever the grassy turf is broken up by the plough.

32. Xanthium strumarium, (L.,) Clot-weed, cockle-bur, (a.) This vile weed, of obscure origin, has the appearance of a naturalized stranger in our country, and seems, fortunately, not much inclined to spread. The burs are a great annoyance in the fleeces of sheep.

33. Xanthium spinosum, (L.,) Thorny Clot-bur, (a.) This execrable foreign weed is fast becoming naturalized in many portions of our country, particularly in the southern States. It may be frequently seen also along the sidewalks and waste places in the suburbs of our northern seaports. “It is stated that the authorities of a southern city a few years since enacted an ordinance against the offensive weed, in which enactment it was denounced by the misnomer of “Canada thistle.” This plant may be destroyed with the hoe in the latter part of summer—in September.

34. Bidens frondosa, (L.,) Bur Marigold, (a.) Worthless native weeds in gardens, corn fields, &c., and particularly disagreeable by reason of the barbed awns of the fruit, which adhere in great numbers to clothing.

35. Bidens bipinnatus, (L.;) Spanish Needle, (a.) This, like the preceding, if not carefully watched and extirpated, is a great pest in cultivated lots. Another species, B. Chrysanthemoides, (Mx.,) known as Beggar-ticks, is rather showy, with its head of yellow-rayed florets, and is frequently found along swamps and rivulets in autumn. They are all regarded as nuisances on account of their adhesive fruit.

36. Maruta cotula, (D. C.,) May-weed, fetid chamomile, (a.) A disagreeable little foreign weed, which is extensively naturalized, and in bad odor among us.

37. Achillea millefolium, (L.) Yarrow, milfoil, nose-bleed, (p.) English agricultural writers speak of it as a plant of some value in their pastures; but it is generally regarded in this country as a mere weed. Certainly it is far inferior to our usual pasture plants, and our cattle are rarely, if ever, observed to eat it.

38. Leucanthemum vulgare, (Lam.,) Ox-eye, daisy, white weed, (p.) This intruder from Europe has obtained almost exclusive possession of many fields in eastern Pennsylvania, and the prospect of getting rid of it appears to be nearly hopeless. Its propagation and diffusion are so rapid and irresistible that one negligent sloven may become the source of a grievous annoyance to a whole neighborhood. The cultivation of hoed crops a few years will rid a field of this obstruction to useful vegetation. The Corn Marigold, Chrysanthemum legetum, (L.,) a kindred plant, which is said to be such a pest to the agriculture of the Old World, happily does not appear to have found its way as yet to the United States.

39. Erechthites hieracifolia, (Raf.,) Fire Weed, (a.) This coarse native weed is remarkable for its prevalence in newly-cleared grounds, especially in and around the spots where brush-wood has been burnt; hence its common name of “fire-weed.”

40. Senecio vulgaris, (L.,) Common Groundsel, ragwort, (a.) A homely worthless little herb, which Professor De Candolle remarks migrates almost everywhere with European men. It is naturalized about the seaports of the northern States, and has lately appeared in eastern Pennsylvania.

41, Centaurea cyanus, (L.,) Ragged Robin, blue bonnets of the Scotch, (a.) This European plant is often seen in our gardens, and in some places is gradually straggling into cultivated fields. As it is considered a troublesome weed among the grain crops of the Old World, it should be watched here, so as to prevent the blue bonnets from “coming over the border.

42. Cirsium lanceolatum, (Scop.,) Common Thistle, (b.) This foreigner, which delights in a rich soil, is abundantly naturalized in Pennsylvania and in the northern States generally. It is a very objectionable weed on our farms, requiring constant vigilance and attention to exclude or keep it in subjection. If permitted to mature its fruit, the expanded pappus may be seen by thousands floating the akenes through the air, and disseminating the obnoxious intruder far and wide. The common thistle, having no creeping roots, is not so obstinate in resisting extirpation as some other varieties. It is easier destroyed if the roots are cut with sufficient care before its flowering season.

43. Cirsium horridulum, (Mx.,) Yellow Thistle, (b.) This rugged, repulsive species looks like a stranger here, being hitherto chiefly restricted to the sandy sea-coast of New Jersey. It is certainly desirable that it should continue to be a stranger to every agricultural district.

44. Cirsium arvense, (Scop.,) Canada Thistle, (p.) This is perhaps the most pernicious and detestable weed that has as yet invaded the farms of our country. Though miscalled “Canada thistle,” it is believed to be indigenous to Europe, and has probably acquired that name by reaching us via Canada. The rhizoma or subterranean stem (which is perennial and very tenacious of life) lies rather below the usual depth of furrows, and hence is not destroyed by common ploughing. The rhizoma ramifies and extends itself horizontally in all directions, sending up branches to the surface, where radical leaves are developed the first year, and aerial stems the second.year. The plant—that is, the aerial portion—appears to die at the end of the second summer like a biennial, but it only dies down to the rhizoma or subterranean stem. The numerous branches sent up from perennial rhizoma soon furnish prickly radical leaves, which cover the ground so as to prevent cattle from feeding where those leaves are. Nothing short of destroying the perennial portion of the plant will rid the ground of this pest; and this has been accomplished by a few years of continued culture, (or annual cropping of other plants which require frequent ploughing or dressing with the hoe,) so as to. prevent the development of radical leaves, and thus deprive the rhizoma of all connexion or communication with the atmosphere. We have a few other thistles which are all worthless weeds; but not being so obnoxious as the preceding, it is not deemed necessary further to notice them here.

45. Lappa major, (Gaertn,) Burdock, (b.) Everybody knows this coarse homely foreign weed, one of the earliest and surest evidences of slovenly negligence about a farm-yard.

46, Cichorium intybus, (L.,) Wild Succory, chicory, (p.) This foreigner is becoming extensively naturalized. Some European agriculturists recommend it as a valuable. forage plant, and cattle seem fond of it; though it is believed to impart a bad taste to the milk of cows which feed upon it. In Europe the roasted root is used as a substitute for coffee. In this country the plant is generally regarded as an objectionable weed.

47. Taraxacum dens-leonis, (Desf.,) Dandelion, (p.) An introduced plant, and now so extensively naturalized in our grass-plots, fields, and meadows that, although not very obnoxious as a weed, it will be found a difficult task to extirpate it. The leaves and flower buds are frequently used, wilted, as a salad, and boiled as “greens,” and the root has been much employed recently in domestic economy, and is esteemed a pleasant and salutary substitute for the coffee berry.

48. Lobelia inflata, (L.) Eye-bright, Indian tobacco, (b.) A native weed possessing acrid properties, and sometimes employed as an emetic, and as an expectorant in asthma.

49. Andromeda mariana, (L.,) Stagger-bush, (s.) This native shrub is very abundant in the sandy districts of New Jersey, where it is reputed to be injurious to sheep when the leaves are eaten by them, producing a disease called the “staggers.” The evidence on this point is not quite conclusive, but if established would cause the bush to be deservedly ranked among the pernicious plants.

50. Plantago major, (L:,;) Common plaintain, way-bread, (p.) This foreign plant is remarkable for accompanying civilized man, growing along his footpaths and flourishing around his settlements. It is alleged that our aborigines call it "the white man’s foot,” from that circumstance. Another foreign species, the Planceolata, (L.,) known as English plaintain, rib-wort, ripple-grass, and buckhorn plaintain, is becoming particularly abundant in our upland meadows or clover grounds. The farmer should keep its seeds from mingling with those of the red clover, and thus injuring the sale of clover seed in the market.

51. Tecoma radicans, (Juss.,) Trumpet-flower, (p.) This showy native climber is often cultivated and admired in the Northeastern States, but in the West, along the Ohio river and its tributaries, it is regarded as an intolerable nuisance.

52. Verbascum thapsus,(L.,) Common Mullein, (b.) An introduced, homely weed in our pastures and cultivated grounds. There is no surer evidence of a slovenly and negligent farmer than fields overrun with mulleins. As the plant produces a vast number of seeds it can only be kept in due subjection by eradication before the fruit is mature. There is another species called moth mullein, V. blattavia, (L.,) more slender, and equally worthless, becoming frequent in our pastures.

53. Linaria vulgaris, ( Mill.,) Toad-flax, Ranstead-weed, (p.) Arather showy, but fetid weed, said to have been introduced into Pennsylvania by a Mr. Ranstead, from Wales, as a garden flower. It inclines to form large, dense patches in our pastures by means of its creeping roots, which take almost exclusive possession of the soil.

54. Nepeta cataria, (L.,) Cat-mint, cat-nip, (p.) This is common about old settlements. Another perennial species, N. Glechoma, (Benth.,) [latter re-classified as Glechoma hederacea -ASC] called ground- joy, and gill, is also common in moist, shaded places about farm houses.

55. Lamium amplexicaule, (L.,) Dead nettles, hen-bit, (a.) A worthless little weed, abundant in and about gardens in the Middle States, requiring some attention to keep it in due subjection.

56. Leonurus cardiaca, (L.,) Motherwort, (p.) A homely, obnoxious weed, found in waste places about houses and farm-yards.

57. Teucrium canadense, (l.,) Wood-sage, germander, (p.) This native plant, which is frequently seen in low, shaded grounds along streams, where it is harmless, has recently got into the fields of some of the best farms of eastern Pennsylvania, where it is now regarded as an obstinately persistent nuisance.

58. Echium vulgare, (L.,) Blue-weed, vipers bugloss, blue devils, (s.) A showy, but vile weed, extensively naturalized in some portions of our country, especially in Maryland and in the Shenandoah valley, Virginia. Wherever it makes its appearance the farmers should act promptly on the Ovidian maxim, “Principius obsia,” &c.: Meet and resist the beginning of evil.

59. Echinospermum lappula, (Lehm.,) Stick-seed, beggar’s lice, (a.) The slovenly farmer is apt to get practically and vexatiously acquainted with this obnoxious native weed in consequence of its racemes of bur-like fruit entangling the manes of his horses and the fleeces of his sheep.

60. Convolvulus arvensis, (L.,) Bind-weed, (p.) This foreign plant has been introduced into some portions of our country, and will give the farmers much trouble if they do not carefully guard against it.

61. Cuscuta epilinum, (Weihe.) Dodder, flax-vine, (a.) This remarkable parasitic plant, somewhat resembling copper-wire in appearance, was introduced with our flax crop, and was formerly a great pest in that crop, by winding round and entangling branches of stalks so as to spoil them; but the vine has become rare, and has nearly died out since the culture of flax has declined among us.

62. Solanum nigrum, (L.,) Night-shade, (a.) Frequent in shaded, waste places about dwellings. It is reputed to be deleterious in its properties, and ought, therefore, to be carefully excluded from the vicinity of all farm-houses, where its berries may tempt children to “pluck and eat.”

63. Solanum carolinense, (L.,) Horse Nettle, (p.) An exceedingly pernicious weed, and the roots are so penetrating and so tenacious of life that it is difficult to get rid of. It was probably introduced from the South by Humphrey Marshall into his botanic garden at Marshallton, Pennsylvania, whence it has gradually extended itself round the neighborhood, and forcibly illustrates the necessity of caution in admitting mere botanical curiosities into good agricultural districts.

64. Datura stramonium, (L.,) Thorn Apple, Jamestown (or Jimson) weed, (a.) Two varieties of this coarse, fetid, narcotic plant (which is probably of Asiatic origin) are common among us as an obnoxious weed, and they should be carefully excluded from the vicinity of all farm-houses.

65. Enslenia albida, (Nutt,) Whitish Enslenia, (p.) This twining plant, allied to the Asclepias or Milk-weed family, and happily as yet unknown to the farmers of the eastern States, is reported by Prof. Short, a distinguished botanist of Kentucky, to be an intolerable nuisance on the farms along the river banks in Ohio, Illinois, &c.

Division III.—Apretatovus Exogens; Corolla usually wanting.

66. Phytolacca decandra, (L.,) Poke-weed, pigeonberry, (p.) This stout native is everywhere frequent in rich soil. The turions, or tender radical shoots, in the spring of the year afford a popular substitute for those of asparagus; nevertheless, the plant is regarded and treated as a weed by all neat farmers.

67. Chenopodium album, (L.,) Lamb’s Quarter, goose-foot, (a.) This coarse and rather homely weed has become common and quite troublesome in gardens.

68. Amaranthus hybridus, (L.,) Pig-weed, (a.) A repulsive looking weed, an annoyance in gardens and cultivated lots in the latter part of summer. If permitted to mature its seed it soon becomes very abundant.

69. Amaranthus albus, (L.,) White Amaranth, (a.) Another coarse weed in the farm yards of the middle States. Although supposed by some to be a native of Pennsylvania, it has a foreign habit and appearance, and probably came from tropical America.

70. Amaranthus spinosus, (L.,) Thorny Amaranth, (a.) This odious bushy weed, supposed to be a native of tropical America, is common in unfrequented streets and outskirts of our seaport towns, and is a vile nuisance wherever it appears. It cannot be too sedulously guarded against. Hoeing on its first appearance is often effectual for its destruction.

71. Polygonm pennsylvanicum, (L.,) Knot-weed, (a.) A common worthless weed on road sides and in waste places about neglected farm-houses.

72. Polygonum pucicaria, (L.,) Lady’s Thumb, spotted knot-weed, (a.) Resembles the preceding, and rather smaller, but equally worthless wherever introduced.

73. Polygonum hydropiper, (L.,) Water Pepper, smart-weed, (a.) A naturalized weed as worthless as most of the species are, though this is even more obnoxious than the preceding, being a highly acrid plant, and sometimes causing obstinate ulcerative inflammation when incautiously applied to the skin.

74. Polygonum sagittatum, (L.,) Arrow-leaved Tear-thumb, (a.) Mowers and haymakers are apt to be familiar with this annoying native weed in the second crop of swampy meadows. Another kindred species, viz. Parifolium, (L.,) or Halbert-leaved Tear-thumb, is an accompanying and equally obnoxious weed. Ditching and draining are the remedies for the evil. Several other Polygonums occur, equally worthless, but rather less offensive.

75. Rumex crispus, (L.,) Sour Dock, curled dock, (p.) An unsightly and objectionable foreign weed, too extensively known.

76. Rumex obtusifolius, Bitter Dock, broad-leaved dock, (p.) This foreign species is now more objectionable than the preceding, but is not quite so prevalent. There is also a little foreign species, well known for its acidity—the R. acetosella, (L.,) Field or Sheep Sorrel, (p.,) often so abundant as to be a nuisance on the farm. Improving the land, especially by adequate dressing of lime, is believed to be the best mode of expelling this and many other obnoxious weeds.

77. Euphorbia hypericifolia, Eye-bright, spurge, (a.) This is a common weed in dry pasture fields, especially in thinnish sandy soils, and has been suspected (how justly has not been determined) as the cause of the disagreeable salivation or slabbering with which horses are sometimes affected in the latter part of summer. There is another flatty, prostrate, bunching little species, E. maculate, (L.,) often abundant in Indian cornfields and other cultivated grounds.

78. Urtica dioica, (L.,) Nettle, stinging nettle, (p.) An exotic rather frequent in waste places about farm houses, well known to those who have come in contact with them.

Class II—Endocenous Plants; Inside Growers.

79. Symplocarpus fatidus, (Salish,) Swamp Cabbage, skunk weed, (p.) A worthless native weed in wet and swampy meadows, readily known by its skunk- like odor when wounded.

80. Sagittaria variabilis, (Englin,) Arrow-head, (p.) A common native plant of no value, found in sluggish ditches and swampy meadows. The roots, or base of stem, often produce large oval tubers in autumn, which tempt hogs to root for them, and thus disfigure the grounds in which they occur.

81. Anacharsis canadensis, (Planchon, Udora, Nutt,) Water-reed, (p.) This slender aquatic is supposed to be indigenous in our sluggish streams, where it often abounds, and may possibly become troublesome in our canals. It has been introduced into England, where its presence impedes the navigation of the canals to a serious extent.

82. Smilax rotundifolia, (L.,) Green Brier, rough bindweed, (p.) This is common in thickets, and a variety of it, S. Caduca, (L.,) often abounds in poor, neglected old fields.

83. Ornithogalum umbellatum, (L.,) Ten O'clock, (b.) This exotic from the gardens in many places multiplies its bulbs so rapidly as to alarm the farmer, if neglected. The bulbs are exceedingly tenacious of life, and when once in possession of the soil, it is an almost hopeless task to get rid of them.

84. Allium vineale, (l.,) Field Garlic, crow garlic, (p.) Tradition says this species was introduced by the first Welsh immigrants to Pennsylvania for the purpose of affording an early pasture, particularly for sheep. It was formerly so abundant in some districts as to be quite an annoyance, by imparting a disgusting flavor to milk and butter, and injuring the manufacture of wheat flour. By good farming and a judicious rotation of crops the evil has been much abated.

85. Juncus effusus, (L.,) Common or Soft Rush, (p.) There are numerous species of this worthless native weed, but this is the best known, and perhaps the most objectionable, as it has a constant tendency to form unsightly bunches, or tussocks, in moist low grounds. Mr, Elliott, an eminent botanist, says that in South Carolina this Rush occupies and almost covers rice fields as soon as they are thrown out of cultivation.

86. Cyperus phymatodes, (Mubl., Nut.,) Grass of Florida, (p.) This species is fortunately somewhat rare, as yet, in the northern and middle States, but it is a great pest to the agriculture of the South.

87. Cyperus hydra, (Mx.,) Coco grass, nut grass of South Carolina, (p) This is regarded by the southern planters as the most intolerable pest of their agriculture. Mr. Elliot says: “It shoots from the base of its stem a thread- like fibre, which descends perpendicularly eight to eighteen inches, and then produces a small tuber. From this horizontal fibres extend in every direction, producing new tubers at intervals of six or eight inches; and these immediately shoot up stems to the surface of the earth, and throw out lateral fibres to form a new progeny. This process is interminable, and it is curious to see what a chain or network of plants and tubers can, with some care, be dug up in a loose soil, The only process yet discovered by which this grass can be extirpated is to plough or hoe the spots in which it grows every day through the whole season. In their perpetual efforts to throw their leaves to the light the roots become exhausted and perish; or, if a few appear the next spring, they can easily be dug up.”

88. Carex tentaculata, (Muhl.,) Many-beaked Sedge, (p.) A very common species, in swampy low ground, of the large and unprofitable genus of sedges.

89. Carex stricta, (Lam.,) Tussock Sedge, (p.) This is one of the most common, and most difficult to manage, of all our sedges. Its roots are apt to form large dense tufts or “tussocks” in swamps. The careful farmers sometimes get rid of those tussocks by digging them out, and, when dry, collecting them in large heaps, burning them, and using the ashes as a manure. Of this remarkable and very numerous genus, (Carex,) Dr. F. Boott, an accomplished botanist of London, has now in hand one of the noblest and most elaborately illustrated monographs ever issued from the press.

90. Panicum sanguinale, (L.,) Crab grass, finger grass, (a.) In the middle States this troublesome grass abounds in gardens in the latter part of summer, and is frequent also in Indian corn fields, but may be kept in tolerable subjection by the early and faithful use of the instrument known as the “cultivator.” The crab-grass is regarded as a serious pest in the plantations along the lower Mississippi.

91. Panicum capillare, (L.,) Hair-like Panicum, “Old Witch” grass, (a.) This worthless species flourishes best in a light sandy soil, but is usually more or less abundant in corn-fields. In autumn the dry culms break off and the light-spreading panicles are rolled over the field by the winds, until they accumulate in great quantities along fence and hedge rows.

92. Panicum crus-galli, (L.,) Cock-foot Panicum, barn-yard grass, (a.) This coarse homely grass is said to be an inhabitant of all quarters of the globe. It is usually found in the latter part of summer, rather abundant along drains of barn-yards and other waste places.

93.  Sitaria glauca, (Beauv.,) Bristly Fox-tail grass, (a.) All our weed-like species of this genus are believed to be naturalized strangers here. This one usually makes its appearance in abundance among the stubble, after a wheat crop, and is frequent in pastures, orchards, &c., when not kept down by a more valuable growth. The S. viridis, (Beauv.,) called green fox-tail or bottle grass, is about equally worthless, but not quite so prevalent.

94. Sitaria virticellata, (Beauy.,) (a.) The adhesive bristles of this species, frequenting gardens and neglected lots, are calculated to make it something of a nuisance if permitted to become abundant.

95. Cenchrus tribuloides, (L.,) Bur grass, hedge-hog grass, (a.) This pestilent nuisance is quite abundant in the sandy districts of New Jersey and along the great northern lakes.

96. Cynodon dactylon, (Pers.,) Dog’s-tooth grass, Bermuda grass, (p.) Of this grass, which has found its way from Europe into Virginia and other southern States; Mr. Elliot remarks: “The cultivation of it on the poor and extensive sand-hills of our middle country,” (viz., in South Caroling “would probably convert them into sheep-walks of great value; but it grows in every soil, and no grass, in close rich land, is more formidable to the cultivator. It must, therefore, be introduced with caution.”

97. Bromus secalinus, (L.,) Cheat, chess, broom grass, (a.) This is a well- known intruder among our crops of wheat and rye, and often appears in the same fields for a year or two after those crops, but it is soon choked out by the perennial grasses.
This plant is an annual, and easy to overcome by care in sowing clean wheat, by keeping fence corners and field borders clear, and in establishing a proper rotation in cropping. The vulgar error, that this grass is merely transmuted wheat, came to us with the earliest immigrants, and, notwithstanding the boasted “march of mind,” it yet prevails among a certain class of farmers to a considerable extent.

98. Triticum repens, (L.,) Couch grass, Quitch grass, (p.) This species of triticum, which is quite distinct in habit from the cultivated wheat, has found its way into some districts of our country, and is a pernicious intruder, when fully introduced, by reason of the exceeding tenacity of life in its rhizomas, or creeping subterranean stems.

99. Andropogon nutans, (L.,) Wood grass, Indian grass, (p.) This and two or three other species of native Indian grasses are common in our sterile grounds, and are no better than mere weeds.

Series II.—Cryprocamus, or Flowerless Plants.

100. Pteris aquilina, (L.,) Brake, bracken of the Scotch, (p.) This large fern is often abundant in moist woodlands and borders of thickets, and in our wild forests it affords a favorite shelter, or hiding-place, for deer and other game, but it is little better than a weed on the farm.

Having thus disposed of the most prominent weeds in our agriculture, it remains merely to mention, very briefly, three or four of the injurious cryptogams, among the lower order of the fungi, viz:

Merulius lachrymans, (Schum.,) Dry-rot. This fungus, with some others which infest timber in places where a damp air is confined, as in houses and ships, is very injurious. It is said to be remedied by a wash of diluted sulphuric acid.

Ascophora mucedo, (Link.,) Mould, bread-mould. This minute fungus usually abounds on moist decayin; substances, and is well known to housewives as growing plentifully on bread and pastry which have begun to “spoil;” yet it is probable that many of them have never suspected it of being as genuine a plant as any weed that grows on the farm.  [Mostly because it isn't a plant, but a fungus, which is very different. -ASC]

Uredo segetum, (Pers.,) Blight, smut, brand. This is usually found within the glumes. and fruit of wheat, barley, and other grasses, speedily filling the whole with a profuse black dust.

Puccinia graminis, (Pers.,) Mildew, rust. This often operates injuriously on wheat crops in warm, close, foggy weather, near harvest time; especially where the crop is a little backward and mingled with grass or herbage.

NOTE.—The following letters are used for the sake of brevity: (p) denotes a perennial plant or root of more than two years’ duration; (b) denotes a biennial plant of two years’ duration; (a) denotes an annual plant living but one year; (s) denotes a shrub or small tree—a woody perennial.