Alfalfa can have disease and insect problems that make it uneconomical to grow, especially in the South. The corn will probably produce a spectacular crop on a field that has been in alfalfa. They are hard to dry well and usually require fairly neutral pH. Clover is often planted in combination with a grass such as timothy, orchard grass, or bromegrass. Upright clovers like red clover are easiest to hay. Ladino clover makes terrific pasture, but most varieties are low-growing, hard to mow, and short persistence.
Palatability can be a problem with clover hays, because of mold and dust from the drying problems.
There is some evidence that red clover retards ovulation in sheep, so it may not be a good hay to feed breeding ewes. Clover, like alfalfa, does not do well in acid soils. Alsike clover grows in poorer soils, but it has been associated with photosensitization, colic, scours, and behavioral aberrations in equines. Hay Birdsfoot trefoil can be hard to establish in some areas, but the upright varieties produce a highly palatable hay. The yield and protein levels are lower than alfalfa, but the delicate stems are often consumed by sheep and other picky animals that reject coarser alfalfa stems.