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ous to stock in much the same way that squirrel-tail is; i. e., it gets into the mouth, producing inflammation and causing severe ulceration. Squirrel-tail grass is abundant where seepage water occurs, and like the brome grass just mentioned causes much injury to stock. Little can be done to check it as long as it is allowed to go to seed.

In Utah another annual brome grass, the quaking brome (Bromus brizaeformis), is often seen, also several species of squirrel-tail grass (Hordeum jubatum, H. caespitosum), common in the East, and wild barley (H. murinum).

Storksbill (Erodium cicutarium) is common on much of the western country to California. Wild oats (Avena fatua) is frequently seen.

In most meadows of Utah there is an abundance of a species of thistle (Cirsium scariosum). It is a large stocky plant with very spiny, light-colored leaves and light purple flowers. In some places the green hellebore (Veratrum viride) is common.

In low meadows or sandy, moist meadows, of the North the common horsetail (Equisetum arvense) is abundant and troublesome. In the Pacific Northwest another large species is common. The common brake (Pteris aquilina) is common and troublesome in the same region. Both the brake and horsetails are poisonous.

Weeds of Grain Fields: Small Grains.-The kinds of weeds found in small grain fields vary with the locality; although some kinds are quite universal. Among these are mustard, corn cockle, cowherb and vetch. Many others are local. Among these may be named Russian thistle, in the West; wild garlic, pennycress, mustard, tumbling mustard, foxtails, crab grass, germander, smartweed, lady's thumb, corn gromwell, Canada thistle in the East and Canada; perennial sow thistle in Minnesota and North Dakota; ragweed, milkweed, artichoke,

morning glory, wild oats, cocklebur, chess (Bromus sccalinus), cockle, cowherb, vetch, rose, etc.

Corn. Many of the foregoing weeds also occur in corn fields. To them we might add velvet weed, shoofly, sida, chicken corn, horse nettle, shoestring, meadow sunflower, cocklebur, artichoke, large ragweed, nut grass, quack grass and buffalo bur.

Weeds of Gardens.-The more important weeds of gardens are prickly lettuce, annual sow thistle, lamb's quarter or goosefoot, purslane or pusley, lady's thumb, pigweed, five-finger, crab grass, horseweed, quack grass and nimble will.

The character of weeds of gardens naturally differs in various parts of the United States. In New England and the Central States such weeds as goosefoot, fall dandelion, smartweed, sheep sorrel, crab grass, common mouseear chickweed, purslane, celandine, shepherd's purse, horse-radish, sweet clover, milk spurge or milk purslane, cheeses, wild carrot, blueweed, corn gromwell, henbit or dead nettle, speedwell, small ragweed, toadflax, burdock, bootjack, prickly lettuce, green foxtail, pigeon grass, buttercups and Canada thistle, chicory, quack grass, are all common weeds.

The weeds of the central northern Mississippi vallev are much the same, except the larger ragweed, squirreltail, Pennsylvania smartweed, bindweed or wild buckwheat (Polygonum Convolvulus); dropseed grasses (Muhlenbergia mexicana and M. glomerata), are abundant, and occasionally night-flowering catchfly (Silene noctiflora). In the latitude of St. Louis, a wild bean (Strophostyles pauciflora), the southern morning glory (Ipomoea hederacea), European bindweed (Convolvulus arvensis), boneset (Eupatorium scrotium), Mexican tea, spiny pigweed, Indian mallow or velvet weed, galinsoga, ironweed (Vernonia noveboracensis), aster (Aster Tradescanti and A. salicifolius), goldenrod (Solidago serotina); the boneset,

asters, goldenrod and European bindweed, are perennial. Marsh elder (Iva ciliata), poverty grasses (Aristida dichotoma), dead nettle or henbit (Lamium anplexicaule), are abundant annuals. The Virginia plantain (Plantago virginica), pokeweed (Phytolacca decandra), Carolina crane's-bill (Geranium carolinianum), turkey-foot grass (Eleusine indica), and sida (Sida spinosa) are the common weeds; the large and small ragweeds should also be inIcluded in this list.

From western Iowa to Denver the weeds are much the same as in Iowa and New England, except the false ragweed or marsh elder, Mexican fireweed, yellow and white sweet clover, Russian thistle, buffalo bur, vegetable oyster plant, wild licorice, tarweed or rosin weed (Grindelia squarrosa), perennial ragweed (Ambrosia psilostachya), prickly poppy (Argemone intermedia), woolly thistle (Cirsium canescens), Fremont's goosefoot (Chenopodium Fremontii) and annual sunflowers (Helianthus annuus and H. petiolaris) are common. The latter are abundant from western Iowa to Texas. The cleome is abundant on the plains.

In the interior basin, awned brome grass, conium, wild barley, peppermint, caraway, horehound (Marrubium vulgare), pineapple weed and black medic are among the common weeds.

In California the more important weeds are wild licorice, spiny cocklebur, wild heliotrope, crowfoot grass. crab grass, milk thistle, storksbill, bur clover, tarweed, wild carrot, etc.

In Maryland and Virginia, wild onion, dandelion, wild carrot, prickly lettuce, sweet clovers, horseweed, cocklebur, Mexican tea and pigweed are common.

In the Gulf states the narrow-leaved sneezeweed, pigweed (Boerhaavia), sida, morning glory (Ipomoea hederacea), croton (C. capitatus and C. monanthogynus), crab grass, etc., are the common weeds, and westward in

Texas the buffalo bur; the prickly poppy (Argemone mexicana) is one of the most common weeds.

Many of these annual weeds are easily exterminated by cultivation, but attention must be paid to weeds which occur in waste places where they produce seeds in enormous quantities. Weed seeds often retain their vitality for a considerable period of time. Even though the first crop is removed, a second crop appears from the seeds buried somewhat deeper in the soil.

Weeds of Vacant Lots.-The vacant lots of all parts of our country are a continual menace to the agricultural community. Many of our worst weeds start in the city. The writer has observed the spreading of orache (Atriplex) from a small beginning in an Iowa city over a considerable area. There are hundreds of acres of Canada thistle in Chicago, and in some streets much of the perennial sow thistle, which is such a menace to the agriculture of Canada, the eastern states, northern Minnesota and North Dakota. The bouncing bet and toadflax are spreading rapidly to the adjacent country from such cities as St. Paul, Minnesota, La Crosse, Wisconsin, and Chicago. The unoccupied lands are great weed patches and in most cases are very unsightly.

In an interesting article on "Weeds of Cities and Towns" by Lyster H. Dewey, the statement is made that "the weeds of cities and villages are usually of the migratory class, cosmopolitan in character, and capable of thriving under a wide range of environment. According to the early European works on botany, plants from Asia, adventive in Europe, usually appeared first in cities. Many of these plants are found about the cities and towns of this country. Others are native plants which have withstood the changed conditions due to cultivation and have acquired a weedlike habit. In the eastern cities and in those on the Pacific coast Old World species predominate, while in the cities of the interior,

especially in those west of the Mississippi river, there is a larger proportion of native plants. The species vary in different cities, in different years, and in different seasons."

These weeds can be removed by sowing these lots and vacant areas with clover and grasses. These plants will effectually prevent the growth of many weeds, except the annual spear grass (Poa annua), dandelion, wild onion (Allium vineale), star of Bethelem (Ornithogalum umbellatum) and cat's-ear (Hypochaeris); or they can be utilized for the growth of vegetables, like the potato.

Where there are large areas, these weeds can be kept down by allowing sheep to graze; this method is followed in New York and Philadelphia. These animals are excellent lawn mowers. The driveways of parks and walks can be kept clean by spraying with iron sulphate or some other herbicide; however, the iron sulphate will be more effective than most of the other herbicides. The method has been described in full in another connection.

In many states there are laws on the extermination of weeds, and while they may be enforced in the country, no attention is paid to them in cities. The municipal authorities should enforce the laws. It may be necessary to appoint a weed commissioner who shall work under the authority of the street or park commissioner. Dewey suggests that "a few good examples, which may be produced through individual effort or by the united action of a small community, will demonstrate the practical utility of the work and lead to its extension. Examples of this kind are now found in many villages and suburban towns. If the practice can be made general in the cities and towns throughout the country it will cut off one of the principal avenues for the introduction of foreign weeds." Roadside Weeds.-There is very little excuse for the appearance of many of the weeds that appear along roadsides, the character of these differing only with the local

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