Definition
Grazing is the practice of feeding livestock by allowing them to consume vegetation growing on pasture or rangeland. For horses, grazing is both a nutritional method and the primary natural behavior through which they spend the majority of their waking hours. A horse kept on well-managed pasture receives fiber, energy, protein, vitamins, and minerals from what it consumes while it grazes.
Nutritional Value of Pasture Grazing
The nutritional value of grazed grass varies with species, season, soil fertility, and growth stage. Cool-season grasses (orchard grass, timothy, fescue) and warm-season grasses (bermuda, bahia) differ in their energy and protein profiles. Spring grass is typically highest in non-structural carbohydrates and protein; summer and fall grass is more fibrous. Horses grazing actively growing pasture often meet or exceed their energy requirements without supplemental grain, making pasture access a cost-effective component of any feed budget. A horse with free access to quality pasture in peak season may not need hay at all during that period.
Pasture Management for Grazing
Managing a pasture for safe, productive grazing involves controlling stocking density (the number of horses per acre), rotating between paddocks to allow regrowth, fertilizing and overseeding to maintain grass density, and removing toxic plants. One horse typically requires two to four acres of pasture to be sustained on grazing alone; below that threshold, supplemental hay is necessary. Overgrazing compacts soil, reduces grass diversity, and creates bare patches that invite weeds. Rotational grazing divides the total acreage into sections that are grazed in sequence, giving each section recovery time.
Grazing and Horse Health
Continuous grazing access supports gastrointestinal health by maintaining steady forage intake, which buffers gastric acid and sustains hindgut fermentation. It also satisfies behavioral needs that reduce stable vices (crib-biting, weaving, stall walking) associated with confinement and boredom. The body condition score of a horse on pasture should be monitored seasonally; lush spring grazing can cause significant weight gain and laminitis in metabolically susceptible animals, while winter pasture may not sustain body condition without supplementation.
Further reading: Grazing on Wikipedia; Grazing at Britannica.