Geographical distribution: Red Clover is a native of Europe, southwestern Asia, parts of Siberia and northern Africa.
History: It was introduced into culture comparatively late. In Italy and Spain its cultivation was established during the fifteenth and sixteenth centuries. It was introduced into Holland from Spain during the sixteenth century and from there it made its way to England during the first half of the seventeenth, the English name being derived from the Dutch "Klafver." It was introduced into North America during the last decennium of the eighteenth century.
Cultural conditions: Being a resident of the temperate zone, Red Clover succeeds best where the summers are not too hot nor the winters too severe. Although the roots go rather deep, the plant is injured by long and continuous drought. It needs sufficient rain during the growing period to enable it to flourish during the whole season. As Red Clover is rather cosmopolitan, a great number of varieties, adapted to different climates, have been developed. The suitability of a variety for a northern climate like that of Canada depends to a great extent upon its hardiness. Chilean Red Clover or other varieties originating in countries with a mild climate are invariably killed by the Canadian winter, except in the southern parts of the country. It is therefore important to secure seed of northern origin. If possible, Canadian grown seed should be obtained because as a rule homegrown seed gives the best results.
Soil: Red Clover can be successfully grown on many kinds of soil, the most suitable being clay loams with a certain amount of lime and plenty of organic matter. Sandy loams also give good returns, especially on limestone foundation; but generally speaking, Red Clover prefers the heavier soils. It can be grown even on stiff clay, provided the subsoil is open. For its proper development Red Clover, like Alfalfa, depends a good deal upon the subsoil. This must be open and well-drained. Stagnant water near or on the surface is decidedly injurious. Water-soaked soil excludes the air necessary for the respiration of the roots and is in a bad physical condition to meet the alternate thawing and freezing of early spring. As is well known, water expands when changing into ice, and if the surface soil contains an abundance of water it will consequently expand when freezing. The overground parts of the plants will be lifted up with the freezing soil. As the lower roots are anchored in the subsoil and therefore unable to follow the upward movement, they will be stretched and sometimes broken. The disastrous effects of alternate freezing and thawing make it evident that one of the first conditions of successful clover growing is well-drained soil.
Habits of growth: Being a biennial, Red Clover devotes the first season's growth to the development of its root system and the accumulation of strength to meet the winter's hardships. It therefore produces a strong tap root, which, if soil and weather are favourable, penetrates to a considerable depth. The overground parts of the plants consist at first of only a few, short, upright stems which carry leaves but no flowers. Later in the season, short leafy shoots are developed which generally lie flat on the ground and are known as the winter tuft. At the same time the tap root begins to contract until its original length is reduced by more than ten per cent. As the end of the root is firmly anchored in the ground, the result is that the overground parts of the plant are pulled down. This process, which has been observed in other plants such as carrots and parsnips, is evidently meant to bring the stems and leaves into close contact with the ground where they are best protected against frost and wind. Early in the spring of the second year the branches of the winter tuft develop into flower-bearing stems, which, if not cut or pastured, produce seed and late in the fall die. The great mass of clover plants arc thus biennial. Red Clover types exist, however, which show a decided tendency to live longer, especially if the plants are kept from seeding by continual cutting or pasturing. The best known of these perennial types is Mammoth Clover.
Agricultural value: No forage plant has been so important to agriculture as has Red Clover. This is due not only to its high feeding value, which is surpassed by few plants, but also to its service as a fertilizer and improver of soil texture. No other leguminous fodder plant is equal to it for these two purposes.
Fodder: Red Clover has its highest feeding value when in full bloom and should be cut for hay before the heads begin to turn brown. If cut late, the stems become woody, lose their palatability and the general value is considerably lessened. The quality of the hay depends to a great extent on the way it is cured. Careless handling causes the leaves to shatter. Exposure to rain or heavy dew discolours the hay, dispels its fine aroma and reduces its nutritive value. Over exposure to sunshine also reduces its feeding value. In curing Red Clover hay methods should therefore be employed by which the drying is done as much as possible by the wind.
Pasture: As a pasture plant, Red Clover is not surpassed by any other legume. It is relished by all kinds of farm animals. On account of the tenderness of the young plants and the necessity to have them start the winter in good condition, it is not advisable in the Prairie Provinces to pasture Red Clover the same year it is sown. In some parts of Ontario, where it may grow rather rank the latter part of the first year, the field is usually pastured; to what extent depends upon conditions. Grazing too late in the fall or pasturing too close by sheep is apt to reduce the succeeding crop. Grazing the second year may begin early in the spring and continue until late in the fall.
When cattle and sheep are turned into a field of Red Clover, there is always danger of bloating, especially if it is wet with dew and the animals start grazing on empty stomachs.