THE GOOD farming practices that are needed for a successful cereal crop are the same whether the crop is grown for feed or seed.
The seeds of small-grained cereals can be produced on nearly all soil types that are well drained and relatively productive.
All cereals yield more seed if they are planted in a well-prepared seedbed that has 2 or 3 inches of mellow surface soil. The surface should be slightly rough to guard against soil movement by water or wind. A good seedbed will help the young plants to emerge promptly and vigorously and compete with weeds. Oats make good growth with less preparation of soil than wheat, barley, and rice.
The first step in the successful production of cereal seed is careful selection of the seeds to be planted. Unadapted seed can be expensive to the farmer.
Carelessness in selecting seeds may mean that the oat field is full of wild oats, a field of winter wheat contains much rye, red rice comes up in a cultivated rice field, or noxious weeds abound in a planting of any of the small cereals.
The production of seeds of small cereals for farmers or seed producers in other areas is not a large enterprise. It is usually a specialty of occasional growers, who are the only ones who should grow a variety not adapted to their own sections. Most growers grow seed adapted to the area in which they are grown.
In some seasons of bad weather or sudden changes in crop acreages, sizable amounts of seed are moved into areas of short supply.
Spring wheat and barley survive in the mild winter climates of the Deep South and the Pacific coast, but plantings in the fall under more rigorous climatic conditions generally end in a poor crop or none.
The hardier winter wheats and barley, if spring planted, will not head or will produce low yields. The buyer must know the variety he buys and its adaptation.
A REGULAR seed producer should plant only adapted varieties, certified to be true to variety and free of noxious weeds and disease. Because the cost of producing seed is much more than the cost of producing cereal grains for feed or food, a grower of seed must plant the best seed he can get. If he grows a crop to maturity and it then fails to meet seed standards, he may realize only the actual cost of production.
Seed should always be treated with a fungicide to guard against smut and other seedborne diseases. Where loose smut is a problem in wheat or barley, only smut-free seed should be used unless the producer has access to equipment for adequate treatment with hot water.
The most reliable source of seed is the certified, registered, or foundation seed recommended and labeled by the experiment station or crop improvement association of the grower's area.
The income per acre from cereals grown for seed is considerably higher than that of those grown for grain and will more than compensate the grower for the extra labor and the higher cost of production.
CEREALS should follow a cultivated crop whenever possible, because that helps to control weeds. Cereals planted for seed should never be planted on land containing noxious weeds. Since it is impossible to clean a field contaminated with mixture of other cereals by roguing, such crop rotation as will leave the fields free of that type of volunteer is imperative.
Little cross-pollination occurs in cereal crops, and isolation is not necessary, but there must be an alleyway between two crops wide enough to enable harvesting without mixture.
In the eastern, southeastern, and Corn Belt areas, it is quite easy to grow any one of the spring cereals immediately following a cultivated row crop. Oats are commonly planted in the Corn Belt the season following a crop of corn.
In sections where winter barley and oats are raised, either may follow cotton. If the winter cereals are to follow a cover crop of lespedeza or other legumes, the field should be plowed at least a month before seeding time for the development of a firm seedbed. Disking or other shallow cultivation is needed to complete preparation of the seed bed.
In the drier parts of the Great Plains, to produce a seed crop of winter wheat without mixtures of volunteer small grains requires planting on land on which grass or a legume crop has been grown.
If spring cereals have to be planted following a summer fallow, a satisfactory crop usually can be produced by a spring cultivation late enough to destroy volunteer grain and weed seedlings before planting.
Wherever corn or sorghum are grown and harvested for ensilage, winter wheat can be seeded without danger of serious mixtures. Summer fallowing is usual every other year in the western sections and the drylands of the Great Plains.
Seed production of cereals usually follows a row crop in the Southwestern States. Two crops of the same species of cereal should not follow one another in the production of seed, except when a certified variety is grown on a field that was used the preceding year to produce certified, registered, or foundation seed of that same variety.
Successful yields have been had in many sections by planting in rows spaced far enough apart to allow cultivation. That practice may be used if unfavorable weather makes it necessary to plant a cereal crop on land that will be quite weedy.
A GOOD METHOD of weed control is through crop rotation and cultivation. If the land is known to contain quite a lot of seeds of any weeds—as often happens following a noncultivated legume crop—cultivation shortly before planting usually destroys enough of the germinated weed seeds to allow the grain to germinate and grow fast enough to control the situation.
It is good farming practice to control weeds in fence rows, turn rows, levees in irrigated fields, and other places where there is little or no plant competition. If an unavoidable condition lets a heavy stand of small weeds germinate and emerge at about the time the grain does, working the field with a rotary hoe or a spike-tooth harrow sometimes helps.
If cereals are planted without being used as a companion crop to legumes or grass, fields can be sprayed with 2,4-D or other chemical sprays for killing weeds. This should be done just before the crop is in the boot stage, which is just before the stems elongate and expose nodes. Because oats and rice are more susceptible to damage after the seed heads start to emerge from the boot, the time of application is extremely important.
If a field of cereals has many large weeds at maturity, spraying with 2,4-D will dry the weeds so that the crop can be combined and stored without damage from excessive moisture. Good farm practices are better than chemicals for the control of weeds.
The grower of cereals is familiar with the recommended rates, dates, and depths of seeding for his area and their modification for his use.
It is quite handy, however, to have a simple method of checking the rate of seeding of his drill: Put the drill in gear and drive a short distance on hard ground. Seeding rate for oats at one-fourth bushel per acre at spacings of 6, 7, or 8 inches will be 1.2, 1.4, and 1.6 kernels per foot, respectively. Wheat will be 2.0, 2.3, and 2.7 per foot. Barley will be 1.7, 2.0, and 2.3 per foot. For example, if 2 bushels of oats are considered a correct seeding rate in a 6-inch drill, there should be 7.2 kernels per foot, which would show a correct calibration.
When cereals are grown under irrigation, soil moisture should be sufficient at seeding time so that the growth will shade the ground by the time of the first irrigation.
SEEDING CEREALS with a grain drill is the most satisfactory method of planting for seed production. It assures a uniform seeding at the proper depth. It puts the seed in moist ground, assures uniform emergence of good stands, and gives the crop a good start in the competition with weeds.
The grower should have some equipment with which to clean a drillbox thoroughly between varieties of cereals planted for seed. A vacuum cleaner may be the easiest to use. Cleaning can be done by running the drill until the seedbox is practically empty and then blowing out the last few kernels from each cup with compressed air. That can be done with a small hand bellows.
If it is suspected that the last crop seeded by a drill contained smut-infected seed, it may be advisable to wash the drill with a solution of a seed-disinfectant chemical.
The drill most commonly used in the United States is the single disk drill with row spacings of 6, 7, or 8 inches.
A hoe-type opener with spring release is sometimes used on rocky land in place of the disk opener. When seeding cereals for seed production with this type of drill, a good practice is to close one or two of the center drill cups in order to facilitate roguing of mixtures from the field.
A GOOD CROP rotation is necessary in all areas for maximum production of seed or grain.
Excellent yields of wheat for food and feed have been produced on well-fertilized land planted to a wheat crop for 3 years. The grower of seed, however, cannot plant wheat or other cereals more than 1 year in succession.
How much fertilizer to apply on cereal crops depends on the soil and the rotation system. The producer of cereal seeds is concerned with fertilizer, as it influences the total yield and viability. Barnyard manure or commercial fertilizers usually are more profitable when they are applied to a high-income crop in a rotation.
If the cropping system involves only cereals or one cereal and fallow, barnyard manure must be applied at least one season ahead of the planting for seed production so that weed or other cereal seeds can be destroyed before the seed crop is planted.
There is little evidence that the various forms of fertilizer show significant differences in yields. The farmer therefore should buy the form that is most economical and feasible for him to use. In many instances he can apply the fertilizer with a fertilizer attachment to his grain drill and thus save the cost of a separate operation.
As the total income anticipated per acre for seed is more than that of grain for other commercial purposes, slightly higher rates of fertilizer may sometimes be justified.
Cereal crops grown in areas of high rainfall or under irrigation can profitably utilize heavy applications of commercial fertilizer.
Rates of nitrogen fertilizer as high as 120 pounds of actual nitrogen to the acre have given profitable yield increases on new soils of low fertility where ample water was available.
Cereal crops planted following sorghum require considerably higher rates of fertilizer than when they follow corn. Grass seed fields leave an unusually heavy root crown residue and require exceptionally high applications of nitrogen to aid the decay of the residue and leave enough nitrogen for a crop. If the preceding crop is a broad-leaved plant and has been heavily fertilized, high yields of cereals can be produced with the fertilizer carryover.
Wheat will utilize more nitrogen fertilizer than barley, oats, and rice. When cool weather follows planting of small cereals, 20 to 30 pounds of actual nitrogen plus phosphate are recommended to carry through a period when plant nutrients are not readily available.
Accurate dates and rates of application are available from experiment stations and extension services.
THE FIRST TIME a seedgrower starts a roguing crew in the field he will become aware of the value of leaving a walkway in the field from which they can operate.
Seldom are single-tillered plants produced in seed production. The primary tiller invariably heads earlier and grows taller than secondary tillers. A roguing crew should be trained to examine carefully and remove the complete plant, because the later tillers will not grow tall enough to be easily observed.
There are three periods when mixtures can be observed more readily than at others: When the head or panicle is just emerging from the boot (mixtures of earlier maturing grains are easily recognized); when plants are just headed and before lodging is likely (offtypes, particularly bearded cereals, are easily recognized); and when a field is mature (mixtures of differences in color or head position, such as curved neck, can be spotted and taken out if lodging is not serious).
Many seedgrowers find it advisable to have the roguers just ahead of the harvesting equipment where mixtures can be observed readily and are easy to get at.
Walking through a ripe grainfield, even though walkways or alleys have been provided, is difficult and destroys a considerable amount of grain by shattering.
Practically never is it possible to grow a cereal crop for seed without roguing the mixtures of offtypes or other cereal contaminants. When the cereal has been planted in rows of 12 inches or more apart, roguing often can be done without walkways.
HARVESTING the seeds is as important as raising the crop.
Improper methods and poor adjustment and operation of harvesting equipment can result in contamination of the seed, excessive losses, and low germination.
Only a small acreage of grain now is harvested with a binder and threshed with a stationary threshing machine. The combine has taken their place.
Collected samples of cereals for storage experiments show practically all seeds to have a quite high count of organisms on the surface. When grain is stored with a moisture content above 12 percent, the air is often humid enough in a sizable pile of grain to start most organisms to grow. This growth will tend to create a considerable rise in temperature and, if the bin is not carefully checked, may mean serious damage to the germination of the stored seed crop. If a careful check shows a rise in temperature, it may be well to remove the grain from the bin and run it through a cleaning mill before putting it back.
Unless adequate drying equipment is available, seed grain should not be threshed until it can be stored safely at a moisture content near 12 percent.
If grain is combined directly from the field and a device for testing moisture is not at hand, moisture can be estimated in the following way: Barley should be ripe and dry enough that kernels bitten with the teeth will snap and appear chalky inside. Oats are ready to combine 7 days after they first appear to be dry and ripe. Wheat can be tested by grasping the base of the head between the finger and thumb of one hand, placing the point of the head against the palm of the other hand, bending it slightly, and rotating it rapidly. At least three-fourths of the heads tested should shell out.
The moisture content of standing rice usually is tested by devices to determine when to begin harvesting milling rice. The same practice should be followed for harvesting fields of rice seed.
Considerable experimental evidence indicates that when rice and small grains are cut or threshed at contents of moisture of seed greater than 20 percent, there is a reduction in the percentage of seed that will germinate.
Men at the Texas Agricultural Experiment Station recommend that seed rice be harvested when the moisture content is 18 percent or less.
WHEAT SHOULD NOT be harvested above a kernel moisture of 20 percent in order to maintain a high germination. This is a recommendation of William H. Johnson, of the Ohio Agricultural Experiment Station, after 3 years of experiments on the combine harvesting of wheat. The same recommendation applies to the harvesting of barley and oats for seed.
When it is necessary to dry a seed crop artificially, the temperature of the drying air should not be greater than 110° F. The independent relation between relative humidity of the drying air and the reduction in germination in small grains has not been established. It is known, however, that the loss of germination tends to increase as air of lower humidity is used to dry the grain.
THE POSSIBILITY of contamination of the harvested seed with other crop and weed seeds can be greatly reduced by thoroughly cleaning all seeding, harvesting, and seed-handling equipment before seeding or harvesting operations are started.
A portable source of compressed air is helpful in cleaning seeding equipment, combine harvesters, stationary threshers, grain elevators, binders, and windrowers.
Seeder or drill boxes and their seed metering units, as well as the tubes and boots, must be cleaned thoroughly to remove seeds of other crops before planting the seed field. All sieve and canvas drapers should be removed from the harvesting machinery and cleaned.
Opening inspection doors and elevator boots and running each piece of machinery empty at rated speed is helpful in removing seed lodged in and around moving parts.
The equipment can be washed with water when compressed air is not available. Attention must be given to the lubrication of bearings immediately after washing.
The seedgrower should always have a copy of the operator's manual for his make and model of combine or stationary thresher. His machinery dealer should be able to supply it. The operator must understand the operation and adjustment of the machine if he expects to harvest the maximum amount of high-quality seed.
The germinating quality of harvested seed is closely related to the amount of cracked, broken, and internally damaged seed. Cylinder speed is normally the main cause of this type of damage. The use of grain blowers to handle the harvested seed also is a factor.
THE ACCOMPANYING table lists a range of cylinder speeds and concave adjustments that will give adequate threshing, without excessive damage to the seed.
The peripheral speed of the cylinder depends on the cylinder diameter and cylinder shaft speed. The larger the cylinder, the slower the shaft needs to turn for a given peripheral speed.
When the cylinder speed is given in feet per minute, the required cylinder r.p.m. (revolutions per minute) can be computed by dividing the cylinder peripheral speed by the product of 3.14 times the cylinder diameter in feet.
THE GERMINATING quality of the harvested seed can also be seriously reduced by grain blowers. That is a result of the same type of damage that is caused by excessive cylinder speed. The impeller shaft speed of the grain blower should be checked and adjusted, if necessary, to the speed recommended by the manufacturer for the particular application.
Feeding the grain blower at considerably lower than the rated handling rates can also result in damage to the grain even when the blower is operated at the proper speed.
The speed of the cylinder and the clearance between the cylinder and concave bars (or the number of rows of teeth in the concave and the overlap between cylinder and concave teeth) should be such that an occasional seed remains in the head and there is little cracked grain in the seed when it is harvested.
The open, bar-type, concave grate should be open to allow maximum separation of seed from the straw at the concave—except when harvesting a seed crop that is difficult to thresh and the straw breaks up badly. Then part or all of the grate should be closed to reduce the amount of chaff going over the shoe as well as increase the threshing action of the cylinder.
| Crop | Cylinder speed, f.p.m. (feet per minute) | Cylinder-concave clearance (inch) | Rows of teeth in concave |
| Barley (6-row varieties) | 4,800 to 5,600 | 1/4 to 1/2 | 2 to 4 |
| Barley (2-row varieties) | 3,200 to 4,000 | 1/4 to 1/2 | 2 to 4 |
| Wheat | 4,500 to 5,500 | 3/8 to 5/8 | 2 to 4 |
| Oats | 5,000 to 6,000 | 1/4 to 5/8 | 2 to 4 |
| Rice | 3,800 to 4,800 | 1/4 to 5/8 | 3 to 6 |
INCREASING the cylinder speed or overlap between the cylinder and concave teeth, reducing the clearance between bar-type cylinders and concaves, or increasing the number of teeth in the concave will all increase the amount of threshing.
An increase in cylinder speed, however, will increase rapidly the amount of damaged seed, even if there is adequate clearance for the seeds in the cylinder.
Increasing the number of teeth in the concave or reducing the cylinder concave clearance generally will not noticeably increase the amount of seed damage until the minimum clearance is about the same as the largest dimension of the seed.
Spike-tooth cylinder teeth should be centered on the concave teeth, and worn cylinder bars or bent concaves should be replaced, so that a uniform clearance is maintained between the cylinder and concave bars.
Better bearding of varieties that have suffered from hot weather or lack of moisture during the seed-forming period can be accomplished by reducing the clean grain sieve opening and thereby returning a high percentage of the seed to the cylinder for re-threshing.
THE COST and time spent in growing and harvesting a seed crop make it quite expensive. It would be foolish to ruin it by using poor equipment to unload it into granaries.
A wind elevator operated with too much pressure can cause enough mechanical injury to make the crop worthless for seed purposes. Damage also may result if auger equipment is run at excessive speeds. The operation of such equipment should be thoroughly checked. A trial run should be made before they are used.