5. The soft corns have no corneous endosperm. The shrinkage in ripening is therefore uniform in all parts of the kernel. To this group belong the mummy corns of Peru and Chili.
6. The sweet corns are characterized by translucent, horny kernels and their more or less crinkled, wrinkled or shrivelled condition. These corns are extensively grown for canning, especially in the eastern parts of North America.
7. The starchy-sweet corns have the lower part of the kernel starchy, the upper part half-horny and translucent. Little is known about this group.
Agricultural value: When Columbus landed in the West Indies, he was presented with a kind of bread made from a grain which the natives called "mahiz." From this word is derived the English maize, under which name the plant is known in Europe. Columbus took corn home with him, but outside of Spain and Portugal the plant was but slowly appreciated in Europe. It is now grown there, especially in Italy, where corn porridge (polenta) is the working man's common food, in Spain, where cakes of corn meal (tortellas) are of great importance, and in the countries along the lower course of the Danube. Latterly it has been grown extensively in Europe, East India and Africa. Its cultivation in Europe, Asia or Africa, however, cannot be compared with its cultivation in America. In South and Central America and in the United States it is grown for both grain and fodder. Its importance as a forage plant increases northwards with latitude; along the northern limits of the corn belt it is grown principally for that purpose.
Fodder: Corn is commonly fed green as a supplement to pasture in the late summer and autumn. It is liked by all kinds of stock, but for soiling it is especially valuable for cattle. It is sometimes cut green and cured into dry fodder, but it is retentive of moisture and difficult to store for winter feeding
When grown for husking, the cured fodder, after the ripened grain is removed, is hard and woody. When cut short for feeding, moistened and left in a pile until fermentation starts, dry corn stover becomes more succulent, is wholesome, and is a cheap, bulky food for store cattle. It is, however, deficient in feeding value when compared with corn cut about two weeks earlier and made into ensilage with the grain.
In Canada, corn is grown as an ensilage crop almost to the exclusion of all others. Even along the northern limits of the corn belt the early dwarf flint varieties, such as the common Eight-rowed Yellow, will yield a larger food value per acre than any other forage crop. The type and variety best suited to the production of ensilage in any locality depend on the length of the growing season and the natural warmth of the soil. The maximum food value per ton is obtained from corn that has reached the glazed stage of maturity, or that stage of ripening when the kernels commence to form a hard crust over their surface. The protein or flesh-forming constituents are then of the greatest amount and highest quality, having developed from nitrogenous substances of a much lower feeding value, which were present in liquid form in the earlier stages of ripening. Ensilage made from corn that has reached only the early milk stage is commonly sour, and although valuable for its succulence, it is markedly deficient as a food for stock when compared with corn that has nearly reached maturity.
It is of first importance to have ensilage corn capable of reaching the glazed stage, even under slightly unfavourable weather conditions, in plenty of time for harvesting before danger of frost; it is of secondary importance to obtain a large yield of both stalk and grain. As a rule, the most profitable variety to grow for ensilage on average soil - the variety that will give the largest food value per acre - is one that may be depended upon to reach full maturity when grown on a warmer soil in the same locality or on a similar soil not more than forty or fifty miles south of it. Experience in ensilage-making invariably demonstrates the wisdom of increasing the acreage of early varieties rather than of depending on large yielding late sorts for the desired tonnage.
For fodder, corn is commonly planted in drills at the rate of from twelve to twenty quarts of good seed to the acre. The drills should be not less than thirty-six inches apart for the short-growing early sorts, and forty-two inches for the tall, late varieties.
When two or more varieties of corn for ensilage are to be planted it is advisable to plant them separate, especially if one of the sorts is taller and later in flowering than the other. When the smaller and earlier varieties are planted in mixture with the larger and later sorts the smaller, early corns are usually imperfectly fertilized and the yield of grain from them is reduced.
Seed: Cross-fertilization between varieties should be prevented if possible. The pollen is carried long distances by wind, and seeds of varieties grown within four hundred yards of each other are apt to be more or less impure.
Both shelled corn and corn in the ear are very retentive of moisture; unless the seed is thoroughly dried before being stored the vitality is apt to be injured or destroyed by heating or severe freezing. When fully ripe, seed corn should be cut and dried on the stalk before husking. If the weather is damp and unfavourable to drying in the shock, the seed should be dried on the ear by artificial means; it should be protected from freezing until the cob is quite dry and brittle. A dark germ with a wrinkled covering shows that the seed has been injured by frost.