What Kind of ‘Corn’ Is That?
If you look closely you can easily identify the stubby upright ears of wheat, the long- bearded ears of barley, the shorter-bearded ears of rye and the dainty heads of oats.
Cereals, which are cultivated grasses, provide the staple food in nearly every part of the world, from the steamy tropics to temperate zones, and even inside the Arctic Circle. Their great importance stems from their ease of cultivation and consequent low price.
A little under half the arable land in the British Isles carries cereals in any one year — a total of about nine million acres. Production is highly mechanised and the crops are grown in vast, open fields to facilitate the use of today’s huge combine harvesters. The cereals are sown in autumn or spring; as they grow they form green carpets over the land. Each seed gives rise to several shoots, and each shoot grows up to produce an ear of grain; as the shoots ripen, they turn golden yellow.
Barley is our second most important cereal and about four million acres are devoted to it at the present time. The ears are surrounded by long bristles called awns. This feature distinguishes barley from most types of wheat (although there are some awned varieties of wheat known as bearded wheats). There are three spikelets at each joint of the ear, although only one may contain grain. When the ears ripen they hang downwards on their relatively soft stems. Wheat straw is tougher, and the ears are usually more or less upright.
Barley ripens more quickly than other cereals and is less susceptible to cold and drought than wheat. It thrives well in the cooler climate and drier soils of eastern England. Barley flour contains little gluten, the substance that makes bread dough elastic, and so it cannot be used for ordinary bread. Most of the crop is used for feeding livestock or to make malt, an essential ingredient in brewing beer.
Barley was once sown mainly in spring, but about half our barley crop is now sown in autumn. Wild oats and other weeds can be a problem with autumn-sown barley, but modern selective weedkillers deal with them quite easily. Autumn-sown barley is harvested earlier than spring-sown crops and has better malting qualities. The crop is fairly resistant to disease, but the loose smut fungus sometimes attacks the developing grain, causing it to burst open and release masses of black sooty spores. Wind is probably the greatest problem, especially when combined with rain, for it flattens the crop and prevents proper drying. The flattened stalks are also more difficult to harvest.
In terms of annual production, wheat is the world’s most important cereal, and about five million acres are sown annually in the British Isles. All cereals require plenty of moisture and sunshine, but wheat needs rather more of both than barley and is mainly grown on the heavier soils of southern and central England.
Three main species of wheat are grown in the world today. The commonest, bread wheat, is almost the only one grown in the British Isles. Only a small amount of our wheat, however, is used for bread-making (combined with gluten-rich Canadian wheat). The rest goes for animal feed and for industrial uses, such as the manufacture of starch and alcohol.
Wheat is sown in late autumn or early spring and harvested in early or late summer respectively. The ears are rather stout and knobbly; and as wheat has a tougher stalk than barley it suffers less from wind damage. Otherwise the crop faces the same problems as barley — weeds, fungal diseases, and soil pests such as cockchafer grubs and leather-jackets. In summer both crops are also attacked by aphids and by hordes of thrips — minute black or brown insects that feed on the developing ears and then leave in vast swarms as the ears ripen. They are often called thunder flies because they tend to fly in thundery weather.
Rye and Oats
Rye and oats were developed more recently than wheat and barley. They were probably weeds in the other cereal crops, but as agriculture spread to cooler regions they were cultivated in their own right because they survive well in cold climates and poor soils. Rye ears have long awns and resemble barley, but they do not droop when ripe. Most of our rye is grown in the far north and on. The sandy soils of East Anglia. Its flour can be made into bread, but it is dark and strongly flavoured. Some rye is used in crisp-bread, but most British rye goes for animal feed.
Oats are easy to recognise for their loosely branched flower heads. Like rye, they can grow anywhere, but are usually confined to the harsher climate of the north. Oat grains are nutritious, but the flour lacks gluten and the bulk of the crop is used for feed.