Along with many other problems that livestock producers have to deal with as a result of the ever changing climate, ergotism can routinely be a concern. Ergot is a fungus that grows on the seed head of cereal grains and grasses. Environmental conditions (cool wet spring followed by hot early summer temperatures) are ideal for the ergot fungus to grow. Delayed harvesting of grass hay because of rain also means that late cut hay may also be at risk of ergotism. Historically rye was commonly affected by the ergot fungus but wheat, barley, oats, brome, fescue, bluegrass, Timothy and other grasses can also be infected. All animals are susceptible to ergot but cattle are often most affected.