Springville, Utah Where does soil come from? •Rocks •Minerals •Organic Matter o A E TOP SOIL B SUBSOIL C R Sagebrush-Cold Desert What are the main components of soil? • Mineral Matter • Air • Water • Organic Matter SOIL COMPONENTS idealized soil 25% AIR FILLED PORES 25 % WATER FILLED PORES 50 % SOIL SOLIDS Soil Components (volume b Note: clays are microscopic in size ! Soil separate particle diameter (mm) ____________________________ Sand . . . . . . . . . 2.0 - 0.05 Silt . . . . . . . . . . 0.05 - 0.002 Clay . . . . . . . . . . <0.002 SAND SILT CLAY Clay minerals photographed with an electron Microscope. Note: they are plate or flake like and are stacked on top of each other. They are electrically charged and act like magnets that attract and hold plant nutrients. What causes soil erosion? Water Wind No Vegetation How did the Canyon Lands of Utah form? What are the FACTORS that make SOIL? TIME 1000’S TO 10,000’S OF YEARS LAY OF THE LAND TOPOGRAPHY LIVING ORGANISMS ANIMALS AND PLANTS CLIMATE HOT/COLD, WIND/RAIN PARENT MATERIAL ROCKS AND MINERALS Physical land features What are some practices Of SOIL CONSERVATION? Terracing Strip Cropping Contour Plowing Tilling Wind Breaks Ground Covers Internet Sites • http://www.tx.nrcs.usda.gov/class/sammy.htm