Clover or trefoil are common names for plants of the genus Trifolium (Latin, tres 'three' + folium 'leaf'), consisting of about 300 species of flowering plants in the legume or pea family Fabaceae originating in Europe. The genus has a cosmopolitan distribution with highest diversity in the temperate Northern Hemisphere, but many species also occur in South America and Africa, including at high altitudes on mountains in the tropics. They are small annual, biennial, or short-lived perennial herbaceous plants, typically growing up to 30 cm tall. The leaves are trifoliate (rarely quatrefoiled; see four-leaf clover), monofoil, bifoil, cinquefoil, hexafoil, septfoil, etcetera, with stipules adnate to the leaf-stalk, and heads or dense spikes of small red, purple, white, or yellow flowers; the small, few-seeded pods are enclosed in the calyx.[3] Other closely related genera often called clovers include Melilotus (sweet clover) and Medicago (alfalfa or Calvary clover).
NCBI taxonomy ID: 3898
Red clover (Trifolium pratense) is a perennial legume species native to Northwest Africa, Europe and Western Asia. Today, red clover is found in many regions around the world including the Americas and Australia. Unlike other legume species, red clover is an outcrossing species due to a strong gametophytic incompatibility system. Red clover is a widely grown fodder legume crop and is valued for its role in increasing soil fertility by nitrogen fixation.
NCBI taxonomy ID: 57577
Trifolium subterraneum, the subterranean clover, is a species of clover native to Europe, Southwest Asia, Northwest Africa and Macaronesia. The plant's name comes from its underground seed development (geocarpy), a characteristic not possessed by other clovers. It can thrive in poor-quality soil where other clovers cannot survive, and is grown commercially for animal fodder. There are three distinct subspecies used in agriculture, each with its own ideal climate and soil type, allowing for wide distribution of the plant over varied environments.
NCBI taxonomy ID: 3900