65. Corn growing.—The full grown corn plant needs so much room that in our corn fields the rows of plants are about four feet apart. Weeds come crowding up between the rows while the corn plants are small. To keep these weeds from shading the corn and getting all its food and moisture, the farmer runs a plow or cultivator between the rows three or four times, while the corn stalks are still small. (Fig. 70.) This way of killing the weeds is much easier than pulling them out by hand as the Indians did. A farmer with two horses in level Illinois can grow fifty times as much corn as an Indian family could by hand work among the dead trees in the woods. This is one reason why we live better than the Indians did.
66. Boys' corn many parts of this country, the United States govern ment helps people to organize boys' corn clubs. Each boy who joins a corn club must grow an acre of corn as directed by the instructor of the club. The object of these clubs is to produce more corn by showing the people the best way to. grow it. The boys often succeed in raising more per acre than their fathers do. In South Carolina, a boy named Jerry Moore grew over two hundred bushels of corn on his corn club acre. How much would 200 bushels of corn cost near your school? 67. Harvesting and shipping the autumn each ear of corn must be taken out of the husks that protect it. This is usually done by hand. Next the corn is hauled to the barn. If the corn is to go to market, the ears are put into a shelling machine that twists the grains off the cob. The shelled corn takes up less space than the ears would take in the corn trains that carry the grain from the farming districts to the great corn markets at Omaha, Kan sas City, St. Louis, Chicago, and Cincin nati. (See Fig. 79.) From these cities, some of this grain goes on to the people in Europe, to whom we send many ship loads each year. The corn map shows the leading seaport cities from which most of the corn ships sail. (Fig. 79.) Take a piece of paper and measure the scale of miles on the map (Fig. 51); then measure the distance from Omaha to Chicago, and on to New York. How far is it? Much travel would be saved if corn could grow in great quantities near the At lantic coast; but the corn map (Fig. 79) shows that instead of being grown near the cities where the ships are, most of the corn is grown in the North Central States, because the land there is better for farming than it is near the Atlantic coast.
68. Smooth land or rough land.—If you should take a trip from Iowa to New England, you would know from looking at the ground why one of these regions is better than the other for growing corn. The land in Iowa is smooth, level, free from stones, and easy to plow. Most of New England is hilly, and sometimes the earth is so full of stones that it is hard to find a place to stick a plow into the ground. This difference shows you why Iowa and the other Central States are so much better for farming than the New England and Middle Atlantic States.
69. How soil is made: decaying rocks make is soil, anyhow? It is only rock, broken up into very small pieces. It seems strange to think that hard rock can become soft dirt. But you have seen many things change their form. You have seen a piece of wood so soft and rotten that you could break it up in your fingers; yet you know that it was once so hard that men drove nails into it.
The hardest of things decay, or break up into many tiny pieces. The sharp knife, or the hard steel chisel that cuts stone, will at last be soft brown rust. You can see a bright new nail or a tack begin to decay in a day or two. Wet it, and the next day it is rusty. You can scrape off the rust with a knife. That rust is a decayed part of the nail. Many boards fall off from fences because the nails which hold them have rusted in two. In just this same way rocks decay, only very slowly. The rain water takes out the part of the rock that holds the grains together. If you look at the walls of an old building, you can see that some of the stone has decayed. Some times you cannot read the letters on old gravestones, because so many particles have dropped to the ground. These par ticles of decayed stone make soil, in which the flowers, grass, grain, and trees grow.
70. Roots break thing that helps to make soil is that all rocks have little narrow cracks in them. Sometimes you can see them, like very fine lines. Into these tiny cracks plant roots push them selves and grow with such force that they widen the cracks a little, and finally break the rocks apart. Every tree has thousands of little roots that are constantly prying into every rock crevice within reach. Some times tree trunks and roots break off a big, solid chunk of stone by growing into cracks in the rock. As time goes on the rocks are thus broken into smaller and smaller pieces until soil is formed.