Kidney Vetch is perennial with a short-branched rootstock from which numerous overground stems arise, from one-half to one foot high. The leaves are numerous, consisting of a number of leaflets in pairs and an odd one much larger than the others. The flowers are in dense heads which are generally in pairs. They are commonly yellow but sometimes white or red. It is a honey plant frequently visited by insects which carry pollen from one flower to another. But if the plants are isolated, so as to make visits by insects impossible, the flowers are automatically fertilized by their own pollen.
It is indigenous to all Europe, except the most northern parts, southwestern Asia and northern Africa.
It grows naturally in dry pastures, along roads and paths, on hills and mountains and in open woods.
Kidney Vetch makes a good stand on sandy or gravelly soil too poor for most leguminous plants. It reaches its highest perfection on land rich in lime. It bears extreme drought without injury and is little affected by alternate freezing and thawing.
In some parts of Europe, where the soil is too poor for Red Clover, Kidney Vetch is quite valuable. It is used for both hay and pasture and is relished by stock. The yield, however, is rather low. Its suitability for Canada is not known.