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Hay facts for kids

Kids Encyclopedia Facts
Hooibaal
A 'square' hay bale
Zetor 7745 (3)
Tractor and a round hay bale

Hay is grass and other plants that have been cut, dried and collected. It can then be stored in piles (called hay stacks), or tied into blocks called bales. Bales can be round or box shaped (usually called square bales).

Hay is mostly used to feed animals. Some animals that eat hay are horses, cattle, goats, donkeys, and rabbits. Hay is fed when there is not enough pasture or rangeland on which an animal can graze or they can't graze year round. Farmers and ranchers often need to use hay in the winter when grass is not available.

Hay is different than straw. Hay is made from leafy grass and other plants (such as alfalfa) and is good for feeding animals. Straw comes from the stems of cereal grains, and is not very nutritious. Straw is normally used for bedding to keep animals warm and dry.

Composition

Roundbale1
Good quality hay is green and not too coarse, and includes plant heads and leaves as well as stems. This is fresh grass/alfalfa hay, newly baled.

Commonly used plants for hay include mixtures of grasses such as ryegrass (Lolium species), timothy, brome, fescue, Bermuda grass, orchard grass, and other species, depending on region. Hay may also include legumes, such as alfalfa (lucerne) and clovers (red, white and subterranean). Legumes in hay are ideally cut pre-bloom. Other pasture forbs are also sometimes a part of the mix, though these plants are not necessarily desired as certain forbs are toxic to some animals.

Oat, barley, and wheat plant materials are occasionally cut green and made into hay for animal fodder; however they are more usually used in the form of straw, a harvest byproduct where the stems and dead leaves are baled after the grain has been harvested and threshed. Straw is used mainly for animal bedding. Although straw is also used as fodder, particularly as a source of dietary fiber, it has lower nutritional value than hay.

Feeding hay

Hay or grass is the foundation of the diet for all grazing animals and can provide as much as 100% of the fodder required for an animal. Hay is usually fed to an animal in place of allowing the animal to graze on grasses in a pasture, particularly in the winter or during times when drought or other conditions make pasture unavailable. Animals that can eat hay vary in the types of grasses suitable for consumption, the ways they consume hay, and how they digest it. Therefore, different types of animals require hay that consists of similar plants to what they would eat while grazing, and likewise, plants that are toxic to an animal in pasture are also toxic if they are dried into hay.

HorsesAndHay
Horses eating hay

Most animals are fed hay in two daily feedings, morning and evening. However, this schedule is more for the convenience of humans, as most grazing animals on pasture naturally consume fodder in multiple feedings throughout the day. Some animals, especially those being raised for meat, may be given enough hay that they simply are able to eat all day. Other animals, especially those that are ridden or driven as working animals, are only free to eat when not working, and may be given a more limited amount of hay to prevent them from getting too fat. The proper amount of hay and the type of hay required varies somewhat between different species. Some animals are also fed concentrated feeds such as grain or vitamin supplements in addition to hay. In most cases, hay or pasture forage must make up 50% or more of the diet by weight.

One of the most significant differences in hay digestion is between ruminant animals, such as cattle and sheep; and nonruminant, hindgut fermentors, such as horses. Both types of animals can digest cellulose in grass and hay, but do so by different mechanisms. Because of the four-chambered stomach of cattle, they are often able to break down older forage and have more tolerance of mold and changes in diet. The single-chambered stomach and cecum or "hindgut" of the horse uses bacterial processes to break down cellulose that are more sensitive to changes in feeds and the presence of mold or other toxins, requiring horses to be fed hay of a more consistent type and quality.

Hayfield in fall
These round bales have been left in the field for many months, perhaps more than a year, exposed to weather, and appear to be rotting. Not all animals can safely eat hay with rot or mold

Different animals also use hay in different ways: cattle evolved to eat forages in relatively large quantities at a single feeding, and then, due to the process of rumination, take a considerable amount of time for their stomachs to digest food, often accomplished while the animal is lying down, at rest. Thus quantity of hay is important for cattle, who can effectively digest hay of low quality if fed in sufficient amounts. Sheep will eat between two and four percent of their body weight per day in dry feed, such as hay, and are very efficient at obtaining the most nutrition possible from three to five pounds per day of hay or other forage. They require three to four hours per day to eat enough hay to meet their nutritional requirements.

Unlike ruminants, horses digest food in small portions throughout the day, and can only use approximately 2.5% of their body weight in feed in any 24-hour period.

Making and transporting hay

Haymaking - geograph.org.uk - 980046
A tractor mowing a hay field, with the cut hay lying in the foreground.
NRCSIA99200 - Iowa (3095)(NRCS Photo Gallery)
A round baler dumping a freshly rolled hay bale
Haytruck
Modern small-scale transport. Pickup truck loaded with "large square" bales

Hay production and harvest, colloquially known as "making hay", "haymaking", or "doing hay", involves a multiple step process: cutting, drying or "curing", raking, processing, and storing. Hayfields do not have to be reseeded each year in the way that grain crops are, but regular fertilizing is usually desirable, and overseeding a field every few years helps increase yield.

Methods and the terminology to describe the steps of making hay have varied greatly throughout history, and many regional variations still exist today. However, whether done by hand or by modern mechanized equipment, tall grass and legumes at the proper stage of maturity must be cut, then allowed to dry (preferably by the sun), then raked into long, narrow piles known as windrows. Next, the cured hay is gathered up in some form (usually by some type of baling process) and placed for storage into a haystack or into a barn or shed to protect it from moisture and rot.

During the growing season, which is spring and early summer in temperate climates, grass grows at a fast pace. It is at its greatest nutritive value when all leaves are fully developed and seed or flower heads are just a bit short of full maturity. When growth is at a maximum in the pasture or field, if judged correctly, it is cut. Grass hay cut too early will not cure as easily due to high moisture content, plus it will produce a lower yield per acre than longer, more mature grass. But hay cut too late is coarser, lower in resale value and has lost some of its nutrients. There is usually about a two-week "window" of time in which grass is at its ideal stage for harvesting hay. The time for cutting alfalfa hay is ideally done when plants reach maximum height and are producing flower buds or just beginning to bloom, cutting during or after full bloom results in lower nutritional value of the hay.

Hay can be raked into rows as it is cut, then turned periodically to dry, particularly if a modern swather is used. Or, especially with older equipment or methods, the hay is cut and allowed to lie spread out in the field until it is dry, then raked into rows for processing into bales afterwards. During the drying period, which can take several days, the process is usually sped up by turning the cut hay over with a hay rake or spreading it out with a tedder. If it rains while the hay is drying, turning the windrow can also allow it to dry faster. However, turning the hay too often or too roughly can also cause drying leaf matter to fall off, reducing the nutrients available to animals. Drying can also be sped up by mechanized processes, such as use of a hay conditioner, or by use of chemicals sprayed onto the hay to speed evaporation of moisture, though these are more expensive techniques, not in general use except in areas where there is a combination of modern technology, high prices for hay, and too much rain for hay to dry properly.

Once hay is cut, dried and raked into windrows, it is usually gathered into bales or bundles, then hauled to a central location for storage. In some places, depending on geography, region, climate, and culture, hay is gathered loose and stacked without being baled first.

Hay must be fully dried when baled and kept dry in storage. If hay is baled while too moist or becomes wet while in storage, there is a significant risk of spontaneous combustion. Hay stored outside must be stacked in such a way that moisture contact is minimal. Some stacks are arranged in such a manner that the hay itself "sheds" water when it falls. Other methods of stacking use the first layers or bales of hay as a cover to protect the rest. To completely keep out moisture, outside haystacks can also be covered by tarps, and many round bales are partially wrapped in plastic as part of the baling process. Hay is also stored under a roof when resources permit. It is frequently placed inside sheds, or stacked inside of a barn. On the other hand, care must also be taken that hay is never exposed to any possible source of heat or flame, as dry hay and the dust it produces are highly flammable.

Modern mechanized techniques

RoundAndSquare
Different balers can produce hay bales in different sizes and shapes. Here two different balers were used to create both large round bales and small square bales.

Modern mechanized hay production today is usually performed by a number of machines. While small operations use a tractor to pull various implements for mowing and raking, larger operations use specialized machines such as a mower or a swather, which are designed to cut the hay and arrange it into a windrow in one step. Balers are usually pulled by a tractor, with larger balers requiring more powerful tractors.

Mobile balers, machines which gather and bale hay in one process, were first developed around 1940. The first balers produced rectangular bales small enough for a person to lift, usually between 70 and 100 pounds (32 and 45 kg) each. The size and shape made it possible for people to pick bales up, stack them on a vehicle for transport to a storage area, then build a haystack by hand. However, to save labor and increase safety, loaders and stackers were also developed to mechanise the transport of small bales from the field to the haystack. Later in the 20th century, balers were developed capable of producing large bales that weigh up to 3,000 pounds (1,400 kg).

Conditioning of hay has become popular. The basic idea is that it decreases drying time, particularly in humid climates or if rain interferes with haying. Usually, a salt solution is sprayed over the top of the hay (generally alfalfa) that helps to dry the hay. Conditioning can also refer to the rollers inside a swather that crimps the alfalfa to help squeeze out the moisture.

Baling

Small bales

Grass hay by David Shankbone
When possible, hay, especially small square bales like these, should be stored under cover and protected from precipitation.

Small bales are still produced today. While balers for small bales are still manufactured, as well as loaders and stackers, there are some farms that still use equipment manufactured over 50 years ago, kept in good repair. The small bale remains part of overall ranch lore and tradition with "hay bucking" competitions still held for fun at many rodeos and county fairs.

Small square bales are stacked in a criss-crossed fashion sometimes called a "rick" or "hayrick". Rain tends to wash nutrition out of hay and can cause spoilage or mold. Hay in small square bales is particularly susceptible to this, and is therefore often stored in a hayshed or protected by tarpaulins. If this is not done, the top two layers of the stack are often lost to rot and mold, and if the stack is not arranged in a proper hayrick, moisture can seep even deeper into the stack. The rounded shape and tighter compaction of small (and large) round bales makes them less susceptible to spoilage, as the water is less likely to penetrate into the bale. The addition of net wrap, which is not used on square bales, offers even greater weather resistance.

People who keep small numbers of animals may prefer small bales that can be handled by one person without machinery. There is also a risk that hay bales may be moldy, or contain decaying carcasses of small creatures that were accidentally killed by baling equipment and swept up into the bale, which can produce toxins such as botulism. Both can be deadly to non-ruminant herbivores, such as horses, and when this occurs, the entire contaminated bale generally is thrown out, another reason some people continue to support the market for small bales.

Large bales

Round bale 3066
Round bales are harder to handle than square bales but compress the hay more tightly. This round bale is partially covered with net wrap, which is an alternative to twine.

Farmers who need to make large amounts of hay are likely to choose balers which produce much larger bales, maximizing the amount of hay which is protected from the elements. Large bales come in two types, round and square. Large square bales, which can weigh up to 1,000 kilograms (2,200 lb), can be stacked and are easier to transport on trucks. Large round bales, which typically weigh 300 to 400 kilograms (660–880 lb), are more moisture-resistant, and pack the hay more densely (especially at the center). Round bales are quickly fed with the use of mechanized equipment.

The ratio of volume to surface area makes it possible for many dry-area farmers to leave large bales outside until they are consumed. Wet-area farmers and those in climates with heavy snowfall can stack round bales under a shed or tarp, but can also use a light but durable plastic wrap that partially encloses bales left outside. The wrap repels moisture, but leaves the ends of the bale exposed so that the hay itself can "breathe" and does not begin to ferment. However, when it is possible to store round bales under a shed, they last longer and less hay is lost to rot and moisture.

Haylage

Heuballen Plastik Steiermark
A completely wrapped silage bale in Austria.

For animals that eat silage, a bale wrapper may be used to seal a round bale completely and trigger the fermentation process. It is a technique used as a money-saving process by producers who do not have access to a silo, and for producing silage that is transported to other locations. However, a silo is still a preferred method for making silage. In very damp climates, it is a legitimate alternative to drying hay completely and when processed properly, the natural fermentation process prevents mold and rot. Round bale silage is also sometimes called "haylage", and is seen more commonly in Europe than in either the United States or Australia. However, hay stored in this fashion must remain completely sealed in plastic, as any holes or tears can stop the preservation properties of fermentation and lead to spoilage.

Haystacks

Haystacks are stacks of harvested hay, stacked in many different ways, depending upon region of the world, climate, if baled or loose, and so on. Hay requires protection from weather, and is optimally stored inside buildings or other structures, but haystacks are also built in an open field. A fence may be built to enclose a haystack and prevent roaming animals from eating it, or animals may feed directly from a field-constructed stack as part of their winter feeding.

Haystacks are also called haycocks in some dialects of English. The words are usually styled as solid compounds, but not always. They are also sometimes called stooks, shocks, or ricks.

Loose hay stacking

Loose stacks are built to prevent accumulation of moisture and promote drying, or curing. In some places, this is accomplished by constructing stacks with a conical or ridged top. The exterior may look gray on the surface after weathering, but the inner hay retains traces of its fresh-cut aroma and maintains a faded green tint. They can be covered with thatch, or kept within a protective structure. One such structure is a moveable roof supported by four posts, historically called a Dutch roof, hay barrack, or hay cap. Haystacks may also be built on top of a foundation laid on the ground to reduce spoilage, in some places made of wood or brush. In other areas, hay is stacked loose, built around a central pole, a tree, or within an area of three or four poles to add stability to the stack.

One loose hay stacking technique seen in the British isles is to initially stack freshly cut hay into smaller mounds called foot cocks, hay coles, kyles, hayshocks or haycocks, to facilitate initial curing. These are sometimes built atop platforms or tripods formed of three poles, used to keep hay off the ground and let air into the center for better drying. The shape causes dew and rain water roll down the sides, allowing the hay within to cure. People who handle the hay may use hayforks or pitchforks to move or pitch the hay in building haycocks and haystacks. Construction of tall haystacks is sometimes aided with a ramp, ranging from simple poles to a device for building large loose stacks called a beaverslide.

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See also

Kids robot.svg In Spanish: Heno para niños

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