Improving Your Own Open-pollinated Corn

By Dr. Harold Willis

If you want to try growing open-pollinated corn, be prepared to go to some extra trouble and care. High quality often takes more work, but it is worth it. After you find an open pollinated variety you like, you can then grow your own seed and improve it year after year to obtain a variety that is “tailor made” for your climate and soil.

Improve your open pollinated corn
Use the mass selection process (detailed below) to get the best seed from your best corn plants.

First, if you are not certain what characteristics you want (high protein, high mineral, high sugar, etc.), buy seed from more than one variety to test. Buy good quality seed with a high germination rate from a reputable company or individual. Some of the large seed companies carry open pollinated seed, as do some small companies and certain individuals. Plant test plots that are separated from one another to avoid cross pollination with other varieties. Be sure your soil is in top-notch condition. Go to extra trouble to control weeds and side dress needed fertilizers. Keep detailed records of all you do: the weather, crop growth and performance, and yield. Test grain for feed value, and if possible do animal feeding tests. Perhaps one variety will prove best for you, or perhaps mixing grain from two or three varieties will give you the best animal feed.

After you have decided on the best variety (or varieties), begin improving that variety by a selection process. There are several ways to improve varieties. The simplest is called mass selection. You just walk through the field (or hunt through the corn crib) and pick out the best looking plants or ears (don’t use cobs from the outside dozen or so rows), collect them (take both ears of two-eared plants) and shell them, mix the kernels all together, and plant that seed next year. Discard kernels at both ends of the cob; those on the central several inches will be more uniform. Sometimes it takes a long time to show much improvement using mass selection.

Another selection process that can give more rapid results is called ear-to-row selection. Again, collect the best ears, but instead of mixing seed from different ears, keep each ear’s seed separate and plant a separate row with each ear (this can be done with an ordinary planter if seed from each cob is put in a separate box). That way you can more rapidly increase the amount of seed from the best ears and eliminate the less desirable characteristics. The best ears from the best rows can be used for next year’s seed. The experimental rows should be in a larger field of the same variety to eliminate stray pollen. To prevent inbreeding in the ear-to-row method, it is best to detassel alternate rows and save seed only from detasseled rows. It would help to record any notable characteristics of each ear, number them, and label each row.

In either method of selection, choose the ears or plants that show the characteristics you want to increase in the next generation, such as height of plant; number of ears; resistance to lodging, disease, or pests; early maturity; ear or kernel size; protein, oil, mineral, or sugar content; yield; etc. But remember that the open pollinated varieties have much genetic variation, not found in commercial hybrids. This genetic variablility is good because it allows the crop to do well in many kinds of conditions. Therefore, don’t expect all plants in the field to look alike, and don’t necessarily choose cobs from identical-looking plants to use for next year’s seed. Instead, focus on the particular traits you wish to increase. It may take several years to get to a desirable level.

After you have developed one or more varieties of your own, you may then want to try variety hybridization to obtain still new varieties of open pollinated corn which may have much improved characteristics. Either two varieties can be planted in alternating rows and be allowed to cross pollinate at random, or one variety can be detasseled and serve as the female parent. The best ears or kernels from detasseled plants can be planted next year. Not all offspring from crosses will have the desired characteristics, but selection over several years may develop a variety that will breed true. Some of the best open pollinated varieties, including the excellent Reid Yellow Dent variety, originated as variety hybrids.

If you engage in growing your own seed corn, you need to take precautions to insure proper storage and good germination. Let the selected ears mature and ripen in the field, but do not let seed be exposed to hard freezes. Select cobs that show the same degree of maturity (all early or all medium). Cobs or seed should be stored in a cool, dry place, away from rodents and stored grain insect pests. Storage at 40–50°F and in a room with a humidity below 13% is best.

Cobs or seed should be laid out so air can circulate. Seed shelled from cobs for ear-to-row planting can be kept in small paper sacks that are left open at the top. If seed corn has to be artificially dried, it should be done slowly at low temperatures (below 107°F). Germination rate should be tested by wrapping about 50 (or more) seeds in a moist paper towel at room temperature. If stored grain pests infest the seed corn (weevils, grain beetles, grain moths), they can be killed without much harm to the seed if the seed is heated to 140°F for 10 minutes. Avoid cracking kernels if a mechanical sheller is used.

From How to Grow Top Quality Corn 

Measuring Corn Quality

By Dr. Harold Willis

Are high quality crops important to you? Is it really worth all the trouble it takes to grow better crops?

If you are feeding your crops to your animals, then you probably can see the value of feeding more nutritious feed and getting higher-producing and healthier animals. Even here, some of the “experts” tell us that it doesn’t pay economically. That it is easier and cheaper to just give the animals vitamin and mineral supplements to make up for what should be in the crops — but isn’t. But is it really better that way?

Often the synthetic vitamins that are used in most supplements aren’t able to be effectively utilized by your animals. Animals (and people) do better when they eat a well-balanced diet containing vitamins, minerals, enzymes, amino acids, proteins, etc., in natural forms.

Even though the nutritionists and biochemists insist it makes no difference, a man-made feed mix or supplement can never have all of the literally hundreds of organic substances contained in the cells of healthy plants — not only vitamins, amino acids, and proteins, but also nucleic acids, nucleotides, peptides, amines, purines, phospholipids, enzymes, coenzymes, flavins, flavenoids, carotenoids, cytochromes, alkaloids, organic acids, polyphenols, and many others you have never heard of.

Even minerals such as calcium must be changed into organic forms by being complexed by a living plant or the microorganisms in an animal’s digestive tract in order for best usage by the animal. So in spite of what the experts say, animals are living organisms and function best when fed high quality, natural food.

OK, you say — so high quality is important when you feed your crops, but I grow corn to sell, and the market only pays for bushels; why should I worry about quality? First of all, you aren’t really paid by volume — bushels — but by weight — a 56 lb. bushel as a standard. The heavier your corn, the more profit you make.

Test weight can be easily measured: Take 2 quarts (dry measure) of corn and weigh in ounces. Subtract the weight of the container. The weight in ounces equals pounds per bushel. For example, if 2 quarts weigh 54 oz., the test weight is 54 lbs. per bushel.

High quality grain will automatically have a higher test weight, plus will not be docked because of cracked kernels or mold. Partly because of the large amount of horribly poor quality grain now being grown, the market is starting to pay a premium for high quality, especially foreign markets. Also, if you grow high quality grain, you should investigate specialty markets which will always pay a premium, such as poultry feed and bird seed companies, zoos, bakeries, and health food companies.

You can also come out ahead in the long run by striving for high quality crops because of the money you can save in grain drying, preservatives, fuel (good soil is loose, easier to work), and veterinary bills, to name a few.

How to tell corn quality

How can you recognize high quality corn, and how can you test your own corn for quality? We mentioned some of the signs of high quality in previous chapters: a deep, strong root system, vigorous growth, freedom from diseases and pests, early maturity with the plant staying green, well-filled cobs (more than one good cob per plant), high test weight, and kernels that do not mold in storage.

Brix standard test corn

Refractometers for corn quality

Another way of measuring crop quality as well as monitoring the plant’s health while it is growing is to use a refractometer to measure sugar content. A refractometer is a precision optical instrument that allows you to quickly measure the percent sugars in the sap of a plant, which is correlated with the plant’s food-producing efficiency (photosynthesis) as well as with food value — protein and mineral content.

Refractometers are routinely used in the food industry, by canneries, wineries, and breweries for example, to measure the quality of the fruits and vegetables they buy from farmers or of the foods and drinks they manufacture.

Using a refractometer is easy. Simply squeeze a few drops of juice from the stems or leaves of the plant onto the glass prism of the refractometer, close the “lid,” and look through the eyepiece. The sugar content is read on a numbered scale in units called Brix (same as percent).

By comparing with standard levels (see Brix table above) or past readings that you have made, you can see how your crops measure up that day. You should realize, however, that the sugar content will vary — from one plant to another, from one part of the plant to another (higher in leaves and upper stalk), in different weather and times of day (higher on warm sunny days in the afternoon), and for sick and healthy plants (sometimes a sick plant will give a high reading if the sugar isn’t being carried into the cob like it should be). So you should be careful to check the sugar content at the same place in the plant (say 3rd leaf-level of the stalk, or cob level), and at the same time of day on sunny days.

corn quality refractometer

Other tests for corn quality

What about standard lab tests for grain and feed quality? One of the most commonly used tests, crude protein, tells you almost nothing. It doesn’t even measure protein, but only estimates it, by multiplying the nitrogen content by 6.25. If there is a high amount of nitrate or other non-protein nitrogen present, the result is meaningless.

Other tests, such as digestible protein, total digestible nutrients (TDN), crude fiber, and dry matter are also estimates of food value. An amino acid analysis is another, more accurate, but very expensive test.

All in all, the cheapest, quickest, and easiest food value test is the sugar content reading made with a refractometer, since mineral content and truly usable protein content are directly correlated with sugar content (unless the plant has a high sugar reading but is obviously sick).

Ordinary lab tests do not measure how well your animals can utilize protein. A crop with a high protein test from a lab but a low refractometer reading would not be as good for animals as one with a high refractometer reading and a lower protein reading.

And then, the ultimate test of crop quality is how well your animals do on it. They should give good gains and production, be healthy, and reproduce well (if other factors are adequate, such as water quality, ventilation, and environment). You can even use the refractometer to test the animals’ urine and immediately see how they are doing on a certain batch of feed.

Source: How to Grow Top Quality Corn

Corn Mazes as Profit Generators

By Ted Bodenrader

“If you build it, they will come.” Several years ago, these words seemingly fell upon the ears of John Kondilis-Hashem, an ambitious young farmer whose skills have graced Bella Organic Farm since 2008. With an eye for business prosperity and a hand for organic cropping, Kondilis-Hashem keenly studied the methods through which neighboring farms were boosting profits and sales. Upon assessing the local competition, he soon realized that his Oregon-based operation was lacking one critical ingredient.

“(Conventional) farms were all offering corn mazes — an attraction for drawing in crowds to their businesses,” he said. “We realized we were one of the only farms in the Portland area not doing one.”

But once the owners of Bella Organic built it — amid the steamy summer of 2010 — the premonition soon rang true. Today, visitors come in droves from the greater Portland region and beyond to lose themselves in the farm’s green-cropped labyrinths, a fun fall diversion from football and leaf-raking.

Although farms typically charge between $10 and $20 per visitor for a two-to three-hour meander through the pathways, the maze itself has not been the primary moneymaker in the case of many organic and sustainable farms.

“We make a little bit of money from the admission prices, but not a great deal,” said Kondilis-Hashem. “Rather, the purpose of the corn maze is to simply lure people to the farm. And boy has it ever. Once we get folks to come out, they end up spending an entire day here and purchasing many of the other things that we offer. We run the maze in conjunction with our pumpkin patch — and that’s where we really clean up. I’ve seen people come here and end up carting out six or seven pumpkins at a time. But the corn maze is what reels them in.”

Likewise, the operators of sustainable Billingsgate Farm have tasted similar success. The husband-wife team of Peter and Lynn Reading were facing an identical predicament as cross-coastal Bella Farm. Situated on the south shore of Massachusetts, a handful of conventional, non-organic farms within the vicinity were opening corn mazes every August through November. Hence, three years ago, Billingsgate jumped aboard the maze craze with its popular new attraction, spanned intricately across three and a half acres of corn husks.

“Once the summer dies down, business drops,” said Lynn. “So we had to come up with a way to draw people back to our farm. We were latecomers; other farms in the area had already been running mazes. But once we opened ours, it made a huge difference with profits. We had more people coming here than ever before.”

When the corn maze spawned overnight success, the Readings opted to add a miniature corn maze for younger children, this one boasting a Jack and the Beanstalk theme. Adding to the dramatic spike in seasonal revenue, Billingsgate also added full concession stands to accompany its corn mazes, transforming it into a family-fun atmosphere. Since introducing the local public to its sizeable corn maze, the farm stands and picking fields (berries and pumpkins) have performed at a higher rate.

“We’re more about agritourism. With the corn maze, we draw city kids from Boston who have never seen a salamander before. It becomes an educational experience for them, which ultimately attracts more interest in our farm. The more time they spend here, the more money we make in our fields and at our stands.”

However, such an endeavor is not without sizeable risks and expenses, as corn mazes can often require hefty investments. A professional maze designer is typically employed by the farm for servicing the maze. Aside from customizing the maze design, these companies often specialize in cutting the maze as well, many times through the use of GPS devices and hi-tech assistance. Additional expenses include various bells and whistles (like games, props or actors) nestled throughout the maze and marketing the autumn attraction through flyers, postcards and online campaigns.

The corn maze at Sweetfields Farm is designed, cut and maintained by the owners to keep costs down

While security measures can also prove somewhat costly, they also prevent potential lawsuits. At Billingsgate Farm, a short video preceding the jaunt through the maze informs visitors of rules and regulations.

The corn itself is a non-edible tropical corn silage that is used for consumption by ruminant animals such as cattle, sheep and goats. Although the silage is slightly more expensive than traditional sweet corn, the ears are never wasted.

Above all, however, there is but one unforeseen risk that crops up every autumn without fail.

“You just never know what Mother Nature has in store for us,” says Reading. “That’s always the greatest challenge; there’s no telling how the weather will affect the turnouts.”

Although corn mazes have become almost a prerequisite for public farms throughout suburban America, organic and sustainable farms are quickly catching on to the growing trend. In Masaryktown, Florida, Ted and Lisa Kessell offer both spring and autumn mazes for visitors to their Sweetfields Farm. In order to reduce expenses, the couple designs, cuts and maintains the mazes themselves. Unlike Bella Farm, the mazes at Sweetfields have morphed into the farm’s primary cash cow.

“Our mazes actually serve as our insurance policy,” says Lisa, pointing to the unpredictable Floridian weather patterns, particularly during the springtime tumult of hurricane season. “Some years, we’ve had substantial financial turmoil due to wind damage and other conditions on the farm. The money that comes in from the corn mazes helps stabilize the profits during these unavoidable catastrophes.”

With the success of their fall corn maze, the couple also launched a springtime attraction that challenges patrons to find their way through a green-leafed sunflower puzzle.

“In the springtime, crops are out of season in Florida, and so business is way down. We needed to come up with a way to bring people to our farm. That’s how we came up with the idea for the sunflower maze.”

With corn mazes catching on across the country, what challenges have awaited these newcomers to the sustainable farming industry?

“There’s really no difference in the way you approach building the corn maze,” said Kondilis-Hashem. “They’re basically made the same exact way (as conventional farms). The corn is planted the same way. The only difference is that we till all of the pathways in the maze, whereas other farms usually spray a (herbicide) solution.”

“It may take a little longer for organic and sustainable farms to create their mazes, because we do everything by hand,” echoes Lisa Kessel. “We can’t use anything that will stray from our policies.”

While organic farms may still be working their way through the proverbial conundrum, a few sensible approaches can help lead them down the proper pathway.

Corn Mazes: Be Different

Never replicate the features offered at a competitor’s corn maze. The allure of each corn maze is in its signature touch. For example, Bella Farm’s maze includes a feature based on the popular classic board game, Clue. With a host of pictures, weapons and clues scattered at various checkpoints throughout the maze, participants can indulge in a two-hour episode of whodunit. Many farms, like Billingsgate and Sweetfields, mark various checkpoints throughout the maze with multiple-choice trivia questions to help guide participants through the passageways. The correct answer points to tunnel light; the wrong answer leads to a dead end.

“We always check out the competition to see what they’re doing,” said Reading. “It’s important to be different.”

Be Scary

Many businesses, like Bella Farm and Rodoni Farms in Santa Cruz, California, transform their corn acreage into a field of screams, offering a Halloween-based approach with the use of ghoulish actors and scary props. With Halloween-themed entertainment on the upswing in recent years, haunted corn mazes have proven a big sell.

“The challenge of a corn maze is enticing,” says Kondilis-Hashem. “But sometimes people just prefer a good scare.”

Be Imaginative

Injecting creativity into the maze each year will bait new customers. For instance, Billingsgate Farm ends its fall season with “Dog Days at the Maze,” allowing visitors to navigate the maze alongside their four-legged companions. The farm has also implemented a new maze tracker feature, whereby participants can use their smartphones to navigate through the tricky twists and turns.

According to Reading, the maze tracker also prevents calls to local police departments (yes, it happens) by patrons stumped by the maze.

Also, many farms remain open for “flashlight hours” in which visitors trek through the husks with the use of strobed wattage, adding to the mystical ambiance.

Change It Up

Perhaps the most noteworthy feature of any corn maze is its theme (or design), which is typically only visible from aerial vantages. However, the overhead snapshot of a snazzy maze design on a farm’s website can serve as an effective marketing tool. This year, Jaemor Farm in Alto, Georgia, launched a maze in the shape of a football player. Bella Farm has sported a different maze design each year, including an image of Dracula, a beaver, a local university sports mascot, and logos for a Portland donut company and beer brewery.

At Billingsgate, patrons have weaved through designs of rainforest and pirate adventure themes. One year’s maze sported a Jurassic Park theme with a figure of the T-Rex dinosaur. At Sweetfields Farm they consistently concoct mazes that are relative to the farm itself.

“We make sure our maze designs are agriculturally related,” said Kessel. “One year, we built a new harvest barn so we decided to design our maze after it.”

Offer Supplemental Attractions

Whereas the corn maze serves as the entrée, side attractions help whet the appetites of fun-hungry visitors. In addition to a spectacular corn maze, many farms sweeten up their repertoires with hayrides, petting zoos, scarecrow contests and other innovative ideas.

This article appeared in the November 2015 issue of Acres U.S.A.

Havesting and Storing Corn

By Dr. Harold Willis

How you go about planting and growing corn depends to a large extent on what you are going to do with it when you get done. Are you growing it for grain? To feed to your animals or to sell? Or are you going to make silage or green chop it? Or perhaps are you growing a specialty crop — sweetcorn for canning, or popcorn?

Each purpose for growing corn has its own set of limitations and desired goals. We will mainly concentrate on growing for grain and for silage (popcorn is harvested as grain, and sweetcorn is harvested early like silage).

Generally, when growing corn for grain, you will want to plant a variety that has a short enough growing season to mature before frost, and plant it early to be sure it gives a high yield. The use of a high quality seed and a seed treatment also helps. On the other hand, for silage, mature grain before frost is not necessary, so you can plant a longer season variety and higher population than for grain.


Ensiling is an excellent method of preserving a nutritious, palatable feed for dairy and feeder cattle, with little waste and easy mechanization. When moist whole corn or ear corn is chopped and packed into an air tight silo (or trench or tube), aerobic bacteria, yeasts, and fungi naturally occurring on the corn plants will begin fermenting the plant material. But in several hours they use up the oxygen they need to remain active, so anaerobic bacteria take over and continue decomposition, producing lactic and acetic acids as by-products.

After about two weeks, conditions are too acid (pH 3.5 to 4.0) for them to remain active, so all microbial activity more or less stops and the silage is preserved. But if there are leaks in the silo or when you begin feeding the silage, oxygen enters and decomposition by bacteria and fungi continues, spoiling some of the silage. Poorly packed silage will also develop pockets of spoilage.

Corn waiting for harvest

The commonly recommended stage of maturity and moisture for harvesting corn for silage is when the kernels have started to harden and glaze,* or when kernel moisture is from 30 to 35% moisture and the total chopped material is 60 to 70% moisture. Water can be added to nearly ripe corn to bring it to the proper moisture so it will pack well.

*This is true of average corn, but with the high quality corn you can raise on good soil, ensiling can be done when the grain is in the milk stage. At that stage the calcium present in the grain is in a form more readily used by animals. Also, high quality grain will have a lower moisture content than average corn at the same stage of maturity.

There are several materials that are sometimes added to silage for various purposes.

  1. Lactobacillus inoculants serve to introduce the right kind of acid-producing bacteria, to insure correct preservation. Although such bacteria are supposed to occur on the corn naturally, the use of an inoculant can be cost effective.
  2. Ammonia and urea are being added to increase the nitrogen content of the silage. It is said that ruminants can use the nitrogen to make extra protein; thus weight gain or milk production increases. This is a band-aid approach. The animals really don’t need protein as much as high energy foods (carbohydrates, oils). High quality feed will have adequate protein already, or else a high quality supplement such as soybean oil meal should. If urea or ammonia are used, they must be balanced by a high energy content feed or else liver damage can occur. Urea can be toxic in too great amounts, and should be mixed thoroughly in the silage.
  3. Gypsum (calcium sulfate) or sodium sulfate are used as a source of sulfur if urea is added; this should not be necessary if high quality feed is used.
  4. Limestone is used in combination with urea to give increased gains, to neutralize strong acid additives (covered next), or else is added to lower the nitrate content of high nitrate feed. Again, high quality feed eliminates these needs.
  5. Propionic acid or other chemical additives (sulfur dioxide, sodium metabisulfite, phosphoric acid, formic acid, sulfuric acid, hydrochloric acid) short-circuit or speed up the attaining of acid conditions, preventing spoilage at high moisture levels. But the desirable partial breakdown of proteins that would occur by bacteria is also short-circuited. Such preservatives should be unnecessary for high sugar content crops (corn, sorghum, Sudan, small grains) and especially not for high quality crops.
  6. Molasses, ground grain, and other carbohydrate sources, or whey are added to increase feed value and palatability, and at the same time to encourage growth of beneficial silage bacteria and speed up the ensiling process. Whey gives the least satisfactory results.


One serious problem that can arise when the whole corn plant is fed to animals is nitrate poisoning, which at high levels produces oxygen deficiency in the animals, evidenced by blue mucus membranes and chocolate-brown blood. Death follows. Milder sub-lethal cases include vitamin A deficiency (pink eye), thyroid disturbances (iodine deficiency), reproductive difficulties, lower milk production, reduced weight gain, and oxygen deficiency.

In a healthy corn plant, nitrates will be made into proteins and stored in the grain, but under certain conditions this does not occur normally and excess nitrates accumulate in lower leaves and especially the lower stalk. The conditions that favor high nitrates in corn stover are:

  1. High available nitrogen or potassium in the soil (from excessive nitrogen and potassium fertilization)
  2. An extreme shortage of phosphorus or potassium (reduces growth while roots continue to take in nitrate nitrogen)
  3. Drought
  4. Barren stalks (no kernels to store proteins in)
  5. Shading of leaves, either from high plant populations or cloudy weather
  6. A heavy rain after a long dry period (roots absorb much nitrate along with water)
  7. Certain herbicides, especially 2,4-D (prevent nitrates from being made into proteins).

If you are forced to use high nitrate feed, here are some points to consider:

  1. Non-ruminants (hogs and poultry) can tolerate more nitrates than ruminants (cattle, sheep). Feed the nitrate feed gradually throughout a day and increase the amount gradually. That way rumen bacteria can adjust and partly detoxify it. Adding grain, molasses, limestone, or live yeast culture to the feed reduces the effect of high nitrate (corn grain has little or no nitrate). Molasses and grain are high energy foods, giving the animals added strength.
  2. Ensiling high nitrate corn reduces nitrates considerably after a few weeks. Do not feed green-chopped fodder, and cut the stalks high (1 1/2 to 2 feet). Delay harvesting as long as possible, since nitrates decrease in time.
  3. Also check for nitrates in the animals’ drinking water. Nitrates in water are absorbed into the blood faster than from food, and they add to what is in the feed, making the problem worse.

Other methods

Green-chop fodder feeding can be an excellent source of nutritious animal feed if the crop is of high quality. In fact, high quality corn fodder can be a complete ration (if essential proteins, vitamins, minerals, and carbohydrates are present in adequate amounts). High quality corn can also be pelletized or baled like hay at the tassel stage or later. Mixing alfalfa or grass forages, straw, or grain with the corn reduces moisture and may improve feed value.

The ideal goal in growing corn for grain is for the grain to completely fill with high levels of proteins, starches, oils, minerals, and vitamins; to become physiologically mature; to grow dry; and for the plant to stay standing until harvest. Some of those terms or concepts may be new to you, so let’s explain them.

High quality corn will have its kernels packed full of nutrients, and as it matures, excess water will be “pushed out,” and it will grow dry enough to store. Physiological maturity means the kernel has reached its highest dry weight, when no more food is being stored in the grain. It is indicated by a “black layer” that forms at the tip of the kernel. The plant should remain green until maturity or beyond. Early-dying plants, dented or shriveled kernels, low test weight, and high moisture grain all indicate low quality. Something went wrong—perhaps weather stress, low soil fertility in the latter part of the growing season, weeds, pests, diseases, etc.

In case you read over it, let’s repeat: high quality corn should not dent (even “dent” varieties will dent little if at all) and should store without molding as it comes out of the field. That sounds hard to believe, I know. High quality corn may have a fairly high percent moisture (perhaps 24 or 28%), but this is “bound moisture,” which is locked into the stored food molecules. It should store without molding. If such corn is artificially dried down to 13% moisture like ordinary corn has to be, its food value will be greatly reduced. It should not be artificially dried. It will also have a high test weight, say 60 or 62 lbs. All of the above refers to truly high quality corn that has not been cut short by an early frost, not to just above average 56 lb. test weight corn, which probably will have to be dried to prevent mold. Sad to say, too much corn being grown these days is 52, 48, or 46 lb.

High moisture corn

Shelled corn or earcorn harvested early at 25–33% moisture and stored in an air-tight (sealed) silo is an excellent animal feed (if it is of high quality). If it is finely ground and firmly packed, high moisture corn can even be stored in conventional silos or trench silos. Storing high moisture corn eliminates any possible need for drying, but it also eliminates the possibility of selling the corn on the grain market. Preservation with propionic or propionic/acetic acids or sodium metabisulfite is often used to prevent mold; this should not be necessary with high quality corn.

Dry grain

For ordinary harvesting of dry earcorn or shelled corn, the kernel moisture content in the field should be from 21 to 28% for average quality corn. As we have said, high quality corn may be as dry as it will get at a higher moisture content than average corn. For storage of average quality earcorn, the kernel moisture should be below 23%, and below 14% for shelled corn. High quality corn will store without molding at higher moisture. Safe storage time is increased the colder the weather and the lower the kernel moisture content. Ear corn can be stored in cribs without the extra expense of ventilators and drying. Grain bins should be well designed and provide adequate ventilation and temperature control.

Grain drying has become a large, expensive, and seemingly necessary part of growing corn these days. But it is really necessary only for average or poor quality corn or to satisfy legal moisture requirements (which were written for poor quality corn). Drying with too high temperature literally cooks the grain, destroys its life, and greatly decreases its food value.

If you must dry your corn, then you must, but it isn’t always necessary to do it the expensive way, using precious fossil fuel. Field drying on the stalk works well as long as there is little lodging. Low temperature drying (with the air heated only several degrees above the outside temperature) takes longer but saves much fuel and doesn’t harm the grain. It is hardly practical with large amounts of corn in cool, humid climates, however. Solar driers have recently been developed and can be home-made. Plans may be available from your state university extension service.


Whether in silage, high moisture corn, or dry grain, molds are a ticking time bomb. The potential danger is immense, and a number of disasters have already occurred. Some fungi are harmless and some, like Penicillium, produce materials useful to us. But other fungi produce poisons, called mycotoxins, which can be deadly. The best known mycotoxins are the aflatoxins, produced by Aspergillus fungi, common among the molds that attack poor quality and too-moist grain. Abnormal or unhealthy crops are most often attacked: cracked kernels of stored high moisture grain or crops damaged by hail or early freeze, or suffering stress from drought and insect damage.

Symptoms of poisoning in animals include impaired liver functions, reduced blood clotting, fragile capillaries and hemorrhaging, kidney damage, impaired immunity to diseases, interference with vitamins A and D and with calcium metabolism, anemia, reduced weight gain and production of milk or eggs, and poor reproduction.

An animal’s milk, eggs, or meat can be contaminated by the toxins, and humans can also be exposed by directly eating food products made from moldy grain (cornmeal, grits, etc., also peanuts).
The common practice is to blend moldy grain with good grain to reduce toxins to “safe” levels before feeding to animals. You should be suspect of any ground feed you buy that wasn’t made from your own grain. A black light screening test to detect molds should be made on all batches of grain or feed that you buy.

To prevent molds from starting in your corn, try to grow healthy, stress-free crops and store grain under cool, dry conditions. Chemical additives for high moisture grain to kill molds may be necessary if quality is not very high.

Source: How to Grow Top Quality Corn