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Hay Quality   arrow

What Type of Forage

The nutritional needs of an animal depend on the type of animal, reproductive cycle, sex, age and use. For optimal production results, match forage quality to animal needs. Feeding animals excessively rich forage wastes nutrients and can result in health problems for the animal. Low quality forage can result in reduced animal performance and increased supplemental feeding costs.

Appraisal of Hay

HayInformation that is useful when evaluating hay includes where the hay was grown, date of harvest, maturity at harvest, method of storage (uncovered, tarped, barn stored) and bale type and size. Also consider the types and amounts of preservatives or drying agents used to treat the hay.

Hay quality can be evaluated using qualitative (sensory) methods or chemical (laboratory) methods.

Qualitative evaluations are based on color, odor, foreign material, leafiness, texture, growth stage and weather damage.

Color: Bright green is the most desirable color for hay. Yellowed hay may be over-mature or sun-bleached. Dark brown or black hay has probably been exposed to excessive moisture. Brown hay may have experienced excessive heat or fermentation.

Odor: Hay should smell fresh. Off-odors such as mildew, mustiness or rotten odors may reduce palatability.

Foreign matter: Non-injurious foreign matter includes material that has little or no feed value but is not harmful to the animal. This includes nontoxic weeds, straw or sticks.

Injurious foreign material includes toxic weeds, blister beetles, wire or other materials that might harm an animal.

Leafiness: Most of the nutritional value of hay is stored in leaves. Hay that is primarily stems usually has low nutritional value. Stemmy hay can result from harvesting when plants are too mature or baling when hay is too dry. Look for hay with a high percentage of soft, non-brittle leaves. Leaves should be attached to the stems to avoid losses during handling.

Mold: If mold is present, determine the degree of discoloration from light cure discoloration to obvious white mold. If mold is present, examine hay for heat damage or fermentation.

Texture: Stems should be soft and pliable, not brittle. Coarse stems indicate over-mature plants and low palatability and nutritional value.

Growth stage or maturity: Most forage plants have an optimal balance of nutritional value and fiber at the early bloom stage. Alfalfa should be harvested at 10 percent bloom. Most grasses should be harvested when seed heads are in the stalk or are just beginning to emerge. Over-mature forage has decreased protein, palatability and digestibility.

Potential weather damage: Weather damage often results in discolored hay. Excessive rain during curing can leach nutrients from the hay.

Chemical analysis

Laboratory analysis to determine acid detergent fiber (ADF), neutral detergent fiber (NDF), relative feed value (RFV), and crude protein (CP) will help you determine the nutritional value of hay.

Acid detergent fiber (ADF) is the percentage of highly indigestible and slowly digestible material in forage. Components that make up the acid detergent fiber (ADF) include cellulose, lignin, pectin, and ash. A low ADF is desirable because it indicates more digestible forage.

Neutral detergent fiber (NDF) is the percentage of plant cell walls or fiber in the forage. This includes acid detergent fiber and hemicellulose. A low NDF percentage is desirable because an animal may consume greater amounts of forage. Feed with extremely low NDF, usually associated with young forage, can result in insufficient dry matter intake. This is rarely a problem when feeding hay.

The relative feed value (RFV) is an index that combines the important nutritional factors of intake and digestibility. The RFV index ranks forages relative to alfalfa at full bloom. Alfalfa at full bloom has an index value of 100.

Crude protein (CP) reflects the nitrogen content and indicates the capacity of feed to satisfy the animal’s protein needs. A moderate to high crude protein value is desirable because it reduces the need for adding supplemental protein to the animal’s diet.

Forage Quality Standards Table






























Values for Alfalfa Hay Harvested at Various Maturity Stages


Maturity Stage




Acid Detergent Fiber





Early bloom






Full bloom



Horse and Cattle Forage Quality Requirements


Relative Feed Value

Heifer, 18-24 months

Dry cow

Idle horse


Brood Mare

Working horse


Heifer, 12-18 months

Beef cow with calf


Nursing mare

Hardworking horse


Dairy cow last 200 days

Heifer, 3-12 months

Stocker cattle


Dairy, 1st trimester

Dairy calf


Types of Hay

Along the Colorado Front Range there are a number of plant species that are used in the production of quality hay. Plants used for hay production include grasses and legumes.

Common grass species for irrigated hay production include smooth brome, orchardgrass, tall fescue, and reed canary grass. Dry land hay species include intermediate wheatgrass, switchgrass and bluestem.

Avoid feeding tall fescue hay to pregnant or lactating horses or cattle. Tall fescue often contains a toxic endophytic fungus. Endophyte-free fescue varieties are available.

Common hay legumes include alfalfa, alsike clover, red clover and white clover. Alfalfa and clovers sometimes contain high protein levels, which can cause colic or bloating.

Printable Hay Buying Checklist Form