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Encyclopedia of Global Resources part 144 provides a wide variety of perspectives on both traditional and more recent views of Earth's resources. It serves as a bridge connecting the domains of resource exploitation, environmentalism, geology, and biology, and it explains their interrelationships in terms that students and other nonspecialists can understand. The articles in this set are extremely diverse, with articles covering soil, fisheries, forests, aluminum, the Industrial Revolution, the U.S. Department of the Interior, the hydrologic cycle, glass, and placer mineral deposits. . | 1336 Wilderness Global Resources Production and Harvest Production of wheat begins with the selection of the seed. So that high yields can be obtained extreme care is taken to select only the highest-quality seed. For winter wheat the seed is planted in the fall generally at the time of the average first frost. This timing allows the crop to make a stand before winter but is not so early that it begins rank growth or starts to send up tall shoots. Spring wheat is generally planted as early as is practical in the spring which is usually early March in the areas where spring wheat is normally grown. In the United States almost all wheat is planted by drilling the seed into the soil. Drilling provides for the best germination and the least amount of winter killing. Harvest time for wheat is determined primarily by the moisture content of the grain. Most wheat in the United States is harvested with mechanical combines and the ideal seed moisture for combine harvest is 12 to 13 percent. After harvesting the grain is taken to the mill. During the milling process the grain is washed and scoured to remove fuzz and foreign material. The grain is then tempered by soaking in water to toughen the bran. After tempering the grain is crushed by a series of corrugated rollers. The bran produced primarily in the seed coat is then separated from the starch. The milled flour is often chemically bleached to improve the color and baking quality and enriched with vitamins and minerals to replace those lost by removing the bran. The average flour yield is 70 to 74 percent of the weight of the grain. D. R Gossett Further Reading Carver Brett F. Wheat Science and Trade. Ames Iowa Wiley-Blackwell 2009. Fageria N. K. V. C. Baligar and R. B. Clark. Physiology of Crop Production. New York Food Products Press 2006. Kipps M. S. Production of Field Crops A Textbook of Agronomy. 6th ed. New York McGraw-Hill 1970. Martin John H. Richard P. Waldren and David L. Stamp. Wheat. In Principles of Field .
