It's not recommended that horses be feed grass clippings, which are basically the type produced by a rotary mower. The small particle size enhances the chance of rapid fermentation in the horse's digestive system, which could potentially lead to colic or laminitis if he eats large amounts. The large clumps of clippings, if conditions are right, can ferment and mold, which is detrimental if the horse eats them. Another concern is that the clippings might contain common ornamental plants that are highly toxic, such as oleander and Japanese yew.
