2010-02-18_REVISION - C1981008 (3)

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produce sustained high yields of crops in an economic manner when treated and mans ed, includin • water, according to acceptable farming methods. In g g general, pnme farmlands have an adequate and dependable. water supply from precipitation or irrigation, a favorable temperature and growing season, acceptable levels of acidity or alkalinity, an acceptable content of salt and sodium, and few or no rocks. They have soils that are permeable to water and air.. Prime farmland is not excessively erodible or saturated with water for a long period of time, and it either does not flood frequently or is rotect flooding. Examples of soils that qualify as prime farmland are Palouse silt loam, O to 7 percent s opes• Brookston silty day loam, drained; and Tama silty clay loam, O to 5 percent slopes. (2) Specific. criteria. 'Soil Survey Manual, Agriculture Handbook 18;" "Rainfall-Erosion from Cropland, Agriculture Handbook 282;" "Wind Erosion Forces in the United States and Their Use in Predicting Soil Loss, Agriculture Handbook 346;" and "Saline and Alkali Soils, Agriculture Ha 60:" Prime farmlands meet all the following criteria: Handbook - (i" The-soils. (a) Aquic, udic, ustic, or xeric moisture regimes and a sufficient available water capacity within a depth of 40 inches 0 meter), or in the root zone (the root zone is the part of the soil that is penetrated or can be penetrated by plant roots) if the root zone is less than 40 inches deep, top ro duce the co • grown cultivated crops (cultivated crops include, but are not limit mmonly ed to, grain, forage, fiber, oilseed, sugar beet,, sugarcane, vegetable; tobacco, orchard, vineyard, and bush fruit crops)-adapted to the region i 7 or more years out of 10; or in (b) Xeric or ustic moisture regimes in which the available water capacity is limited, but the area developed irrigation water supply that is dependable has a • for the crops commonly grown} and of adequate quality; or, _ 5???O ,? (c) Addic or tonic moisture regimes, and the area has a developed irrigation water s I that :f dependable and of adequate quality. y s 007he soils have atemperature regime that is frigid, mesic, thermic, orhyperthermic er elic and regimes are excluded). These soils have, at a depth of 20 inches (SO cm), a mean annual tem erattuu is higher than 32o F (Oo C). In addition, the mean summer temperature at this depth in soils with an ,O horizorr.is higher than. 47o F (8o C); it is higher than 59o F (15o C) in soils that have no O horizo (m) The soils have n the root zone` if the root zone is less than 40 inches deep. (1 meter) or in (iv) The soils either have no water table or have a water table that is maintained at a sufficient de th during the cropping season to allow cultivated crops common to the area to be grown. P (Revised June 2008) Attachment 2.04.9-3-45