Laserfiche WebLink
657.5 Identification of important farmlands. <br />(a) Prime farmlands. <br />(1) General. Prime farmland is land that has the best combination of physical and chemical <br />characteristics for producing food, feed, forage, fiber, and oilseed crops and that is also <br />available for these uses (the land could be cropland, pastureland, rangeland, forest land, or <br />other land but not urban or built-up land or water areas). It has the soil quality, growing season, <br />and moisture supply needed to produce sustained high yields of crops in an economic manner <br />when treated and managed, including water, according to acceptable farming methods. In <br />general, prime farmlands have an adequate and dependable water supply from precipitation or <br />irrigation, a favorable temperature and growing season, acceptable levels of acidity or alkalinity, <br />an acceptable content of salt and sodium, and few or no rocks. They have soils that are <br />permeable to water and air. Prime farmland is not excessively erodible or saturated with water <br />for a long period of time, and it either does not flood frequently or is protected from flooding. <br />Examples of soils that qualify as prime farmland are Palouse silt loam, O to 7 percent slopes; <br />Brookston silty clay loam, drained; and Tama silty clay loam, O to 5 percent slopes. <br />(2) Specific criteria. Terms used in this section are defined in USDA publications: "Soil <br />Taxonomy, Agriculture Handbook 436;" "Soil Survey Manual, Agriculture Handbook 18;" <br />"Rainfall-Erosion Losses from Cropland, Agriculture Handbook 282;" "Wind Erosion Forces in <br />the United States and Their Use in Predicting Soil Loss, Agriculture Handbook 346;" and <br />"Saline and Alkali Soils, Agriculture Handbook 60." Prime farmlands meet all the following <br />criteria: <br />(i) The soils have: <br />(a) Aquic, udic, ustic, or xeric moisture regimes and a sufficient available water <br />capacity within a depth of 40 inches (1 meter), or in the root zone (the <br />root zone is the part of the soil that is penetrated or can be penetrated <br />by plant roots) if the root zone is less than 40 inches deep, to produce <br />the commonly grown cultivated crops (cultivated crops include, but are <br />not limited to, grain, forage, fiber, oilseed, sugar beet, sugarcane, <br />vegetable, tobacco, orchard, vineyard, and bush fruit crops) adapted to <br />the region in 7 or more years out of 10; or <br />(b) Xeric or ustic moisture regimes in which the available water capacity is <br />limited, but the area has a developed irrigation water supply that is <br />dependable (a dependable water supply is one in which enough water <br />(Revised June 2008) Attachment 2.04.9-4-2