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Characteristics of high quality hay

In order to make or to buy superior hay, stock-men need to know what constitutes hay quality. They need to be acquainted with those recognizable characteristics of hay which indicate high palatability and nutrient content. If in doubt, the animals will tell them, for they like and thrive on high quality hay.

The easily recognized characteristics of hay of high feeding value are:

1. It is made from plants cut at an early stage of maturity, thus assuring the maximum content of protein, minerals and vitamins, and the highest digestibility.

2. It is leafy, thus giving assurance of high protein content.

3. It is bright green in color, thus indicating proper curing, a high carotene or provitamin A content, and palatability.

4. It is free from foreign material, such as weeds, stubble, etc.

5. It is free from must or mold and dust.

6. It is fine stemmed and pliable - not coarse, stiff and woody.

7. It has a pleasing, fragrant aroma; it "smells" good enough to eat.

Cure properly so that (a) the hay can be stored safely without heating excessively or becoming moldy, and (b) the maximum leafiness, green color, aroma, nutrient value and palatability shall be retained. To the end that these desired objectives may be achieved, the following information is pertinent:

a. Moisture content:

Freshly cut forage contains 75 to 80 per cent moisture; where as the maximum moisture content for safe hay storage is as follows:

- For loose hay - 25% moisture
- For baled hay - 20 to 22% moisture (the lower figure for larger bales)
- For chopped hay - 18 to 20% moisture
- For cubes - 16 to 17% moisture.

Hay of a higher moisture content than indicated should not be stored because (1) its value may be greatly lowered due to mold or to nutrient losses accompanying fermentations, and (2) of the ever present danger of spontaneous combustion and a costly fire.

Two rule-of-thumb methods used by farmers in determining when hay is dry enough for storage are:

(1) The Twist Method: Twist a wisp of the hay in the hands. If the stems are slightly brittle and there is no evidence of moisture on the twisted stems the hay can be stored safely.

(2) The Scrape Method: Scrape the outside of the stems with the finger or thumb nail. If the epidermis can be peeled from the stem, to is not sufficiently cured. If the epidermis does not peel off, the hay is usually dry enough to stack or put in the mow.


Many conditions and characteristics are either associated with or determine the nutritive quality of hay. It is impossible to predict from one known characteristic of hays the amount of animal response that will be obtained. Among the more important known conditions or characteristics affecting hay quality are: (1) the time during the season and the growth stage at which forage is harvested, (2) whether the forage represents a first growth (not previously harvested or grazed during the same season) or an aftermath growth, (3) leaf content, (4) extent to which the harvested forage is damaged by weather mud handling, (5) physical form in which it is fed, and (6) forage species.


The following hay making pointers are frequently of interest and pertinent:

1. Brown hay: Brown hay results when, due to inclement weather, hay wilted to about 50 per cent moisture content is stacked or placed in storage. The damp mass soon ferments extensively, and heats (preferably not higher than 175° F.). As a result of this action, the hay darkens in color, from dark brown to nearly black. Also, it becomes sweet, aromatic and palatable. But as a result of the fermentation and heating to which it is subjected, the forage is lowered in digestible protein, in total digestible nutrients, in vitamin content, and in feeding value.

Because of its lowered nutrient and feeding value and the danger of spontaneous combustion, therefore, the intentional making of brown hay is not recommended.

2. Salt and other so-called preservatives:

Farmers in many countries of the world have, traditionally, added about 20 pounds of salt per ton of new hay, in the belief that the salt would prevent the hay from molding and heating. Carefully controlled experiments have failed to substantiate claims that salt will prevent excess heating or sweating; nor has it prevented spontaneous combustion of hay However, when salt is used in moderate amounts it may improve the color, aroma, and palatability of poor quality hay. It is recognized, too, that much higher levels of salt quantities sufficiently high to harm animals may prevent mold.

Recently, so-called "hay preservers", most of them consisting chiefly of ordinary baking soda, have appeared upon the market. Usually the directions recommend the addition of 1 to 3 pounds of these products to each ton of damp hay, and "guarantee" that there will be no heating or molding. To date, controlled experiments have failed to substantiate the claims made for these products.

3. Spontaneous combustion:

Wet hay ferments and generates heat. Sometimes this results in spontaneous combustion and fire, usually about a month to six weeks after storing. Here are the facts:

a. Symptoms of heating: The warning signals are: hay that feels hot to the hands, strong burning odor, and visible vapor.