Corn stover consists of the

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

, stalks, and cobs of

corn Maize (; ''Zea mays''), also known as corn in North American English, is a tall stout Poaceae, grass that produces cereal grain. It was domesticated by indigenous peoples of Mexico, indigenous peoples in southern Mexico about 9,000 years ago ...

(maize) (''Zea mays'' ssp. ''mays'' L.) plants left in a field after

harvest Harvesting is the process of collecting plants, animals, or fish (as well as fungi) as food, especially the process of gathering mature crops, and "the harvest" also refers to the collected crops. Reaping is the cutting of grain or pulses fo ...

. Such stover makes up about half of the yield of a corn crop and is similar to

straw Straw is an agricultural byproduct consisting of the dry wikt:stalk, stalks of cereal plants after the grain and chaff have been removed. It makes up about half of the crop yield, yield by weight of cereal crops such as barley, oats, rice, ry ...

from other cereal grasses; in Britain it is sometimes called corn straw. Corn stover is a very common agricultural product in areas of large amounts of corn production. As well as the non-grain part of harvested corn, the stover can also contain other weeds and grasses.

Field corn Field corn is a North American term for maize (''Zea mays'') grown for livestock fodder (silage and meal), ethanol, cereal, and processed food products. The principal field corn varieties are dent corn, flint corn, flour corn (also known as sof ...

and

sweet corn Sweet corn (''Zea mays'' convar. ''saccharata'' var. ''rugosa''), also called sweetcorn, sugar corn and pole corn, is a variety of maize grown for human consumption with a high sugar content. Sweet corn is the result of a naturally occurring rec ...

, two different types of maize, have relatively similar corn stover.

Uses

Fodder (ensilaged or nonensilaged)

Corn stover (like various other kinds of stover) can be used as feed, whether grazed as

forage Forage is a plant material (mainly plant leaves and stems) eaten by grazing livestock. Historically, the term ''forage'' has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used m ...

, chopped as

silage Silage is fodder made from green foliage crops which have been preserved by fermentation (food), fermentation to the point of souring. It is fed to cattle, sheep and other ruminants. The fermentation and storage process is called ''ensilage'', ' ...

to be used later for

fodder Fodder (), also called provender (), is any agriculture, agricultural foodstuff used specifically to feed domesticated livestock, such as cattle, domestic rabbit, rabbits, sheep, horses, chickens and pigs. "Fodder" refers particularly to food ...

, or collected for direct (nonensilaged) fodder use.

Maize Maize (; ''Zea mays''), also known as corn in North American English, is a tall stout grass that produces cereal grain. It was domesticated by indigenous peoples in southern Mexico about 9,000 years ago from wild teosinte. Native American ...

forage is usually ensiled in cooler regions, but it can be harvested year-round in the tropics and fed as green forage to the animals. In the silage use case, it is usual for the entire plant (grain and stover together) to be chopped into pieces which are then crushed between rollers while harvesting. Maize silage is one of the most valuable forages for ruminants. In

dairy farming Dairy farming is a class of agriculture for the long-term production of milk, which is processed (either on the farm or at a dairy plant, either of which may be called a dairy) for the eventual sale of a dairy product. Dairy farming has a h ...

, corn silage is primarily used as fodder for

dairy cows Dairy cattle (also called dairy cows) are cattle bred with the ability to produce large quantities of milk, from which dairy products are made. Dairy cattle generally are of the species '' Bos taurus''. Historically, little distinction was ...

during the winter season. Corn stover can be beneficial to

beef cattle Beef cattle are cattle raised for meat production (as distinguished from dairy cattle, used for milk (production)). The meat of mature or almost mature cattle is mostly known as beef. In beef production there are three main stages: cow-calf opera ...

producers because the "corn stover can provide a low cost feed source for mid-gestation beef cows". In addition to the stalks, leaves, husks, and cobs remaining in the field, kernels of grain may also be left over from harvest. These left over kernels, along with the corn stover, serve as an additional feed source for grazing cattle. Over time, the stalks will decrease in value as feed, so farmers aim to graze the corn stover as soon as possible after harvest. The amount of grazing possible on a field of corn stover is "between one and two months of grazing per cow per acre (50 cows on for one to two months)." When corn stover is harvested intact (as opposed to the whole plant being chopped for silage, or the stover being left in the field by a combine), it can be cut and gathered by corn binders, which are reaper-binders designed specifically for maize. It can also be baled into large round bales.

Bedding (litter) followed by soil amendment

Instead of feed uses, corn stover can also be collected for use as

bedding Bedding, also called bedclothes or bed linen, is the materials laid above the mattress of a bed for hygiene, warmth, protection of the mattress, and decorative effect. Bedding is the removable and washable portion of a human sleeping environment ...

or litter for the livestock (that is, cellulosic bulk to catch and contain the animal

manure Manure is organic matter that is used as organic fertilizer in agriculture. Most manure consists of animal feces; other sources include compost and green manure. Manures contribute to the fertility of soil by adding organic matter and nut ...

), or it can be a vegetable manure that stays in the field as

plant litter Plant litter (also leaf litter, tree litter, soil litter, litterfall, or duff) is dead plant material (such as leaves, bark, needles, twigs, and cladodes) that has fallen to the ground. This detritus or dead organic material and its constituent ...

(serving as

green manure In agriculture, a green manure is a crop specifically cultivated to be incorporated into the soil while still green. Typically, the green manure's Biomass (ecology), biomass is incorporated with a plow or disk, as is often done with (brown) man ...

, although less

green Green is the color between cyan and yellow on the visible spectrum. It is evoked by light which has a dominant wavelength of roughly 495570 nm. In subtractive color systems, used in painting and color printing, it is created by a com ...

than some others, with a higher C/N ratio). When used as bedding (barn litter), it is then removed and directly spread on the fields or

compost Compost is a mixture of ingredients used as plant fertilizer and to improve soil's physical, chemical, and biological properties. It is commonly prepared by Decomposition, decomposing plant and food waste, recycling organic materials, and man ...

ed (in long piles handled by loaders) for later field spreading. In either of the latter two use cases, it ends up as

organic matter Organic matter, organic material or natural organic matter is the large source of carbon-based compounds found within natural and engineered, terrestrial, and aquatic environments. It is matter composed of organic compounds that have come fro ...

for

soil amendment A soil conditioner is a product which is added to soil to improve the soil’s physical qualities, usually its fertility (ability to provide nutrition for plants) and sometimes its mechanics. In general usage, the term "soil conditioner" is often ...

Direct soil amendment

The feed and bedding uses of corn stover are common, but the plant litter/vegetable manure use is also common. The latter is true for any combination of two reasons: (1) it helps to maintain

soil health Soil health is a state of a soil meeting its range of ecosystem functions as appropriate to its environment. In more colloquial terms, the health of soil arises from favorable interactions of all soil components (living and non-living) that belong ...

, and (2) when the corn crop is used as a grain crop (as opposed to a silage crop), harvesting the (grainless) stover simply does not pay; there is often no market demand for it that outweighs its value on the farm as soil maintenance, which represents an economic factor of its own. Regular annual harvesting of the whole corn plant (chopping for silage) is more challenging to

soil management Soil management is the application of operations, practices, and treatments to protect soil and enhance its performance (such as soil fertility or soil mechanics). It includes soil conservation, soil amendment, and optimal soil health. In agricult ...

than is using the corn as a grain crop and mulching the field with the stover. Reincorporating the organic matter is good for the soil, although it must be managed properly to prevent nitrogen robbery of the next crop, as the high C/N ratio causes available nitrogen (fixed nitrogen) to be hoarded by the soil microbes diligently digesting the cellulose and lignin. They can outcompete the plants for the nitrogen. There are both organic and nonorganic ways to augment the nitrogen supply. Animal

urine Urine is a liquid by-product of metabolism in humans and many other animals. In placental mammals, urine flows from the Kidney (vertebrates), kidneys through the ureters to the urinary bladder and exits the urethra through the penile meatus (mal ...

and

is the main organic way, whereas commercial

fertilizer A fertilizer or fertiliser is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from liming materials or other non-nutrient soil amendments. Man ...

is the main nonorganic way; both ways provide

urea Urea, also called carbamide (because it is a diamide of carbonic acid), is an organic compound with chemical formula . This amide has two Amine, amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest am ...

, which the microbes digest with their

urease Ureases (), functionally, belong to the superfamily of amidohydrolases and phosphotriesterases. Ureases are found in numerous Bacteria, Archaea, fungi, algae, plants, and some invertebrates. Ureases are nickel-containing metalloenzymes of high ...

Bioenergy

Another use for corn stover is as fuel for

bioenergy Bioenergy is a type of renewable energy that is derived from plants and animal waste. The Biomass (energy), biomass that is used as input materials consists of recently living (but now dead) organisms, mainly plants. Thus, Fossil fuel, fossil fu ...

or as

feedstock A raw material, also known as a feedstock, unprocessed material, or primary commodity, is a basic material that is used to produce goods, finished goods, energy, or intermediate materials/Intermediate goods that are feedstock for future finishe ...

for bioproducts. It can be burned in furnaces to yield energy that

steam turbine A steam turbine or steam turbine engine is a machine or heat engine that extracts thermal energy from pressurized steam and uses it to do mechanical work utilising a rotating output shaft. Its modern manifestation was invented by Sir Charles Par ...

s convert to

electricity Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwel ...

. It also has potential for

cellulosic ethanol Cellulosic ethanol is ethanol (ethyl alcohol) produced from cellulose (the stringy fiber of a plant) rather than from the plant's seeds or fruit. It can be produced from grasses, wood, algae, or other plants. It is generally discussed for use as a ...

(biomass ethanol), which is "ethanol made from non-grain plant materials known as

biomass Biomass is a term used in several contexts: in the context of ecology it means living organisms, and in the context of bioenergy it means matter from recently living (but now dead) organisms. In the latter context, there are variations in how ...

." However, with current technology, a large part of the

biofuel Biofuel is a fuel that is produced over a short time span from Biomass (energy), biomass, rather than by the very slow natural processes involved in the formation of fossil fuels such as oil. Biofuel can be produced from plants or from agricu ...

potential of

cellulose Cellulose is an organic compound with the chemical formula, formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of glycosidic bond, β(1→4) linked glucose, D-glucose units. Cellulose is an important s ...

is wasted due to the strength of the

glycosidic bond A glycosidic bond or glycosidic linkage is a type of ether bond that joins a carbohydrate (sugar) molecule to another group, which may or may not be another carbohydrate. A glycosidic bond is formed between the hemiacetal or hemiketal group o ...

s that pair chains of D-glucose units. But if the commercialization of cellulosic ethanol advances enough technologically, biomass ethanol production would use the corn stover from the corn crop produced in areas around ethanol plants. Corn stover, due to the relative close proximity of the corn grain produced for ethanol production, "is by far the most abundant crop residue readily available today." The free accessibility to corn stover makes it a prime candidate for biomass ethanol production.

DuPont Dupont, DuPont, Du Pont, duPont, or du Pont may refer to: People * Dupont (surname) Dupont, also spelled as DuPont, duPont, Du Pont, or du Pont is a French surname meaning "of the bridge", historically indicating that the holder of the surname re ...

opened a facility in Nevada, Iowa, that was expected to generate 30 million gallons annually of cellulosic biofuel produced from corn stover residues. The plant provisionally opened in 2015, but shut down in 2017 after a previous temporary shutdown in 2016. DuPont repaid $10.5 million of the $17.5 million in incentives received from the state of Iowa. DuPont sold the plant to a German company, Verbio, who converted the plant from ethanol production to renewable natural gas production for eventual use as compressed natural gas (CNG) or liquified natural gas (LNG) vehicle fuel. Humus is also produced as a byproduct of natural gas production. Humus, alternatively known as digestate, is a value-added lignin- and nutrient-rich soil amendment similar to peat moss or compost which may be returned to feedstock suppliers or further processed into marketable products. As of 2021, Verbio is considering adding back ethanol production capabilities to the plant.

Composition and properties

HHV: 19 MJ/kg DAF

References

{{DEFAULTSORT:Corn Stover Maize