Editing Hay (section)

== Composition ==
[[File:Bales from corn stems 01.jpg|thumb|Baled [[Maize|cornstalks]]<ref>{{cite web | url=https://extension.illinois.edu/beef-cattle/baled-cornstalks | title=Baled Cornstalks &#124; Illinois Extension &#124; UIUC }}</ref>]]

[[File:LPCC-548-Fenc de civada.jpg|thumb|Good quality hay is green, not too coarse, and includes plant heads, leaves, as well as stems.]]
[[File:Round hay bale, partially eaten.jpg|thumb|Poor-quality hay is dry, bleached out and coarse-stemmed. Sometimes, hay stored outdoors will look like this on the outside but still be green inside the bale. A dried, bleached or coarse bale is still edible and provides some nutritional value as long as it is dry and not moldy, dusty, or rotting.]]

Commonly used plants for hay include mixtures of [[pasture|grasses]] such as [[ryegrass]] (''Lolium'' species), [[Timothy-grass|timothy]], [[Bromus|brome]], [[fescue]], [[Cynodon|Bermuda grass]], [[orchard grass]], and other species, depending on region. Hay may also include [[legume]]s, such as [[alfalfa]] (lucerne) and [[clover]]s ([[Trifolium pratense|red]], [[Trifolium repens|white]] and [[Subterranean clover|subterranean]]).<ref name="Iowa">{{Cite web|title=Hay | work = Living History Farms, Iowa |url=https://www.lhf.org/learning-fields/crops/hay/|access-date=2021-06-26}}</ref> [[Legume]]s in hay are ideally cut pre-bloom. Other pasture [[forb]]s are also sometimes a part of the mix, though these plants are not necessarily desired as certain forbs are toxic to some animals.

In the UK some hay is harvested from traditionally managed [[hay meadow]]s which have a highly diverse [[flora]] and which support a rich eco-system. The hay produced by these meadows is species rich and was traditionally used to feed horses.<ref>{{cite web|url=https://www.wildlifetrusts.org/habitats/grassland/northern-hay-meadow|title=Northern Hay Meadows|publisher=Wildlife Trusts|access-date=23 May 2023}}</ref>

[[Oat]], [[barley]], and [[wheat]] plant materials are occasionally cut green and made into hay for animal [[fodder]], and more usually used in the form of [[straw]], a harvest byproduct of stems and dead leaves that are baled after the grain has been harvested and [[Threshing|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.<ref name="Iowa" />

In [[agroforestry]] systems are developed to produce [[tree hay]].

It is the leaf and seed material in the hay that determines its quality, because they contain more of the [[nutrition]] value for the animal than the stems do.<ref name="Deere-1957">{{Citation |author=Deere and Company |author-link=John Deere |year=1957 |title=The Operation, Care, and Repair of Farm Machinery |edition=28th |chapter=23: Hay conditioners |publisher=Deere and Company |location=Moline, Illinois, USA |oclc=965865819 |asin=B000FNB7WM |postscript=.}}</ref>{{rp|194}} Farmers try to harvest hay at the point when the seed heads are not quite ripe and the leaf is at its maximum when the grass is mowed in the field. The cut material is allowed to dry so that the bulk of the moisture is removed but the leafy material is still robust enough to be picked up from the ground by machinery and processed into storage in bales, stacks or pits. Methods of haymaking thus aim to minimize the shattering and falling away of the leaves during handling.<ref name="Deere-1957"/>{{rp|194}}

Hay production is highly sensitive to weather conditions, particularly during the harvest period. In drought conditions, both seed and leaf production are stunted, resulting in hay with a high ratio of dry, coarse stems that possess very low nutritional value. Conversely, excessively wet weather can cause cut hay to spoil in the field before it can be baled. Consequently, the primary challenge and risk for farmers in hay production is managing the weather, especially during the critical few weeks when the plants are at optimal maturity for harvesting. A lucky break in the weather often moves the haymaking tasks (such as mowing, [[tedding]], and baling) to the top priority on the farm's to-do list. This is reflected in the [[idiom]] ''to [[wikt:make hay while the sun shines|make hay while the sun shines]]''. Hay that was too wet at cutting may develop rot and mold after being baled, creating the potential for toxins to form in the feed, which could make the animals sick.

After harvest, hay also has to be stored in a manner to prevent it from getting wet. Mold and spoilage reduce nutritional value and may cause illness in animals.  A [[symbiotic]] fungus in [[fescue]] may cause illness in horses and cattle.<ref>{{Citation|url=http://www.uaex.edu/Other_Areas/publications/PDF/FSA-3042.pdf |archive-url=https://web.archive.org/web/20010614113946/http://www.uaex.edu/Other_Areas/publications/PDF/FSA-3042.pdf |archive-date=2001-06-14 |url-status=live
|publisher=[[University of Arkansas]] Division of Agriculture |title=Managing Fescue for Horses FSA3042 |quote=Cattle grazing fescue often develop a chronic, unthrifty condition, especially apparent during the summer months. In addition, some cattle occasionally develop lameness and lose portions of their feet and tails during fall and winter. Some mares grazing fescue have reproductive problems during the last trimester of pregnancy. |first1=Steven M.|last1=Jones|first2=Mark|last2=Russell}}</ref>

The successful harvest of maximum yields of high-quality hay is entirely dependent on the coincident occurrence of optimum crop, field, and weather conditions. When this occurs, there may be a period of intense activity on the hay farm while harvest proceeds until weather conditions become unfavourable.