THE NORTHERN WHEAT REGION 88. General view.—If we should take an automobile journey late in July and travel northwestward through south ern Minnesota, we should notice that in the course of the day's journey there are fewer and fewer fields of tall, tasseled corn and moreand morefields of wheat. This would mean that we were crossing one of those lines of gradual change along which climate causes crops to change. We would be leaving the Corn Belt and entering the Northern Wheat Region, where the summer is too cool and too short for We could ride on for days and days, d go several hundred miles across a wide, level, treeless plain, and every day, at almost every hour of the day, we should see scattered farm houses and fields of wheat and oats. This sec tion is called the Northern Wheat Region because here wheat is the chief thing the farmer has to sell. Wheat is as important to him as cotton is to the farmer of the Cotton Belt.
We should notice also that here the wheat was still green at a season when, a short distance away in Iowa and Nebraska, wheat was being threshed. What is the reason for this differ ence? Climate gives the answer. When is wheat sown in the Prairie Corn and Small Grain Belt? (Sec. 74.) 89. The spring wheat cli the Northern Wheat Region the winter is so cold and dry that winter wheat, which is sown in the fall (Sec. 74), does not live well there. There fore varieties called spring wheat are grown. The minfall of the Northern Wheat Region is in most years wonderfully suited to spring wheat. During the spring thaw, the soil is moist enough to be plowed easily, and there are few rains to disturb the planting, which is done in April and May; hence the name, spring wheat. Most of the rainfall of the year comes within a few months after the wheat is planted (Fig. 89) and the wheat plants grow like tall, thick grass. Wheat and all the other grain plants are just big grasses. In late summer the rains grow less at the very time when the wheat needs the sunshine and dry weather to ripen it.
90. Sur face and soil.— The best part of this Northern Wheat Re gion is the Red River Valley of the North, comprising part of Minnesota, part of North Dakota, and a large area in Manitoba. As the glacier (Fig. 53) that
once covered northern North America slowly melted away, it stood as a dam across this valley. What is now the Red River Valley was then a very large lake of muddy glacial water, which had an outlet over the divide into the Minnesota River (Fig. 54). When the glacier finally melted, the water of this lake flowed into Hudson Bay, leaving the old lake bed a plain so flat that often you can not guess which way its waters will flow. The soil is rich and as soft and fine as meal, for it is made of the mud that settled on the bottom of the lake. There are no forests on most of this land. There is no better place in the whole world to use farm machines, for there is not a stick, stone, stump, root, or hill to interfere with their work.
Northwestward from this wide, flat valley, the wheat region extends on over tens of thousands of square miles of other good land very much like that of the Prairie Corn and Small Grain Belt. The region yields large crops of wheat, oats, barley, rye, and flax seed.
91. Bounds.—Most of the boundaries of the Northern Wheat Region are made by climate. We do not know just where they are, because weather is always uncertain, and men have not been in the Northwest long enough to become fully acquainted with the climate. Men are learning more and more about raising crops in new countries, so that land once thought to be useless is now divided up into good farms. The eastern boundary of the Northern Wheat Region is the eastern edge of the plain and the beginning of a rough, rocky country. (Sec.
333.) The northern boundary is the line where the summer becomes too short for grain to ripen. In the northern part of the wheat belt the grassy plain is dotted with small ponds, lakes, and clumps of trees. As you go north, the trees increase in number, until finally the whole plain is covered with a forest that extends many hundreds of miles to the northward. The southern part of this forest may some day be cleared and turned into farms, if the climate is found to be suitable, and if more room for farms is needed. Here and there in a forest clear ing as far north as 60° N. latitude, some fur trader raises a little field of wheat.