A perennial legume, capable of very high production if fertility is high and moisture adequate. Its ability to fix atmospheric nitrogen makes a substantial contribution to the growth of companion grasses. It is very suited to irrigation and has a poor drought tolerance, making it of little use in low rainfall areas. However, a small amount is often added to pasture mixes in these drier areas in the hope it will survive in damp spots. White clover can also behave as an annual in drier areas, regenerating from seed when conditions are favourable. White clover uses stolons to expand the size of plants and put down new roots.