If a horse is kept in a pasture, the amount of land needed for basic maintenance varies with climate, an animal needs more land for grazing in a dry climate than in a moist one.  An average of between one and 3 acres (12,000m2) of land per horse will provide adequate forage in much of the world, though hay or other feed may have to be supplemented in winter or during periods of drought. To lower the risk of laminitis, horses also may need to be removed from lush, rapidly changing grass for short periods in the spring and fall (autumn), when the grass is particularly high in non-structural carbohydrates such as fructans.  Horses turned out to pasture full time still need to be checked frequently for evidence of injury, parasites, sickness or weight loss.