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roots are numerous and fibrous. They cannot go down into the soil so deeply as the larger clovers; hence, the dwarfing effect of dry seasons upon the growth.
This plant is exceedingly hardy. It comes out from under the snow with a green tint, and the leaves are not easily injured by the frosts of autumn. The growth is not rapid until the general late rains of spring fall freely. It then pushes on rapidly, and, sending up innumerable flower stems, turns the pastures in which it abounds into immense flower gardens in the months of May and June, according to the latitude of the locality. The bloom remains out for a considerable time, and free grazing has the effect of prolonging the period of bloom. Under such conditions, blossoms continue to form and mature seeds during much of the summer. When these escape being grazed, they fall down upon the land and aid in forming additional plants. Hence it is that when white clover has once possessed a soil, it so stores the land with seed possessed of so much vitality that subsequently white clover plants grow, as it were, spontaneously on these lands when they have been thus grazed event for a limited term of years.
The power of this useful plant to travel and possess the land is only equalled by that of blue grass. When timber lands are cleared, white clover plants soon appear, and in a few years will spread over the whole surface of the land. But the amount of grazing furnished by it varies greatly with the character of the season. Some seasons its bloom
is scarcely in evidence; other seasons it overspreads the pastures.
While it is an excellent pasture plant for stock, they do not relish it so highly as some other pasture plants; when forming seed, it is least valuable for horses, owing to the extent to which it salivates them. Its diminutive habit of growth unfits it for making meadows, unless in conjunction with other hay plants. In nutritive properties, it is placed ahead of medium red clover. Some growers have spoken highly of it as a pasture plant for swine.
Being a legume, it has the power of enriching soils with nitrogen, but probably not to so great an extent as the larger varieties of clover. Its rootlets, however, have a beneficent influence on the texture of soils, because of their number, and because of the power of the stems to produce fresh plants, which occupy the soil when other plants die. The latter furnish a continued source of food to other grasses, which grow along with white clover in permanent pastures.
Along with blue grass, white clover plants aid in choking out weeds. This result follows largely as the outcome of the close sod formed by the two. But in some soils, plants of large growth and bushes and young trees will not thus be crowded out.
Distribution. —White clover is certainly indigenous to Europe and to the Northern States, and probably Western Asia. It grows in every country in Europe, but with greatest luxuriance in those countries which border on the North Sea, the climates of which are very humid, and more especially
in the Netherlands and Great Britain. It stands in high favor in Holland, but is not regarded so highly in England, owing, probably, to the great variety of grasses grown there in permanent pastures. It is generally thought that it was not indigenous to the Southern States, but has reached these from those farther north. It would seem to be capable of growing in all countries well adapted to the keeping of cattle; hence, it follows in the wake of successful live-stock husbandry.
White clover seems able to adapt itself to a great variety of climatic conditions. Nevertheless, it is certainly better adapted to a moderately cool climate than to one that is hot, and to a moist, humid climate than to one that is dry. It has much power to live through dry seasons, but it will not thrive in a climate in which the rainfall is too little for the successful growth of small cereal grains. Where snow covers it in winter, this clover will grow on timber soils as far north as any kind of cereal can be made to mature; and it will also grow as far south as the Mexican boundary on the higlier grounds, when there is enough moisture present to sustain it.
It would probably be correct to say that this plant is found in every State in the Union, and that it şucceeds well in nearly all the Northern States, from sea to sea. Although it grows well in certain parts of the Southern States, especially in those that lie northward, the general adaptation in these is not so high as in those further north. The highest adaptation in the United States is probably found in the Puget Sound region and in the hardwood
timber producing areas of the States which lie south from the Great Lakes and in proximity to them, as Northeastern Minnesota, Northern Wisconsin, Michigan, Ohio and New York. But the adaptation is also high in the more elevated of the mountain valleys of the Northwestern States when irrigated waters may be led on to these lands. The areas lowest in adaptation are those that lie within the semi-arid belt. The low-lying lands of the South, where hot weather is prolonged in summer, are likewise low in their adaptation, but not so low as the former. The prairie areas of the Northern Mississippi basin have an adaptation for growing white clover that may be termed intermediate, but where hardwood forests grow naturally on these the adaptation is high. In New England the climatic conditions are very favorable, much more so than the soil conditions.
In Canada, conditions are found highly favorable to the growth of this plant in the country lying eastward from Lake Huron, north of Lakes Erie and Ontario and also on both sides of the St. Lawrence River. Adaptation is also high along the Pacific and in the mountain valleys not distant from the Pacific. In all the areas of Canada, which once produced forests, this plant will grow well. But north from Lakes Huron and Superior, the soil conditions are against it, because of their rocky character. Certain forest areas west from Lake Superior, and also in other parts, the sandy soils of which sustain a growth of Jack Pine (Pinus murrayana) trees, do not grow white clover with much vigor.
The prairie areas of Canada, westward from Lake Superior to the mountains, do not grow white clover with much success, and the adaptation for its growth would seem to lessen gradually until the Rocky Mountains are approached.
Soils.—Small white clover will grow on almost any kind of soil, but by no means equally well. Highest, probably, in adaptation, especially when climatic conditions are considered along with those of soil, are the clay loams west of the Cascade Mountains and northward from California to Alaska. During the moist months of early summer, this plant turns the pastures in these areas into a flower garden. Almost equally high in adaptation are the volcanic ash soils of the Rocky Mountain valleys. When amply supplied with water, the finest crops of white clover can be grown even superior to those grown on the lands described above. Almost the same may be said of what are termed the hardwood timber soils, which are usually made up of clay loam lying upon clay. Such areas abound in Minnesota, Wisconsin, Michigan, Ontario and some States further south. In these soils it grows with mucii luxuriance, more especially when lime and potash are abundant. Similar luxuriance may be looked for in the deposit soils of river basins in which the clay element predominates, but not in those that are largely made up of sand. It will also grow well on the stiffest clays, whether white or red, when moisture is present. On prairie soils, the success attending it is dependent largely on their texture, composition and the moisture which they