Identification and impact of excess soil potassium on crop and livestock nutrition

Several soils have been identified in the Intermountain West which contain excessive amounts of extractable potassium (K). A "normal" ammonium acetate extractable potassium level may be from 200 to 500 parts per million (ppm), while the high potassium soils contain 1,000 to over 7,000 ppm. Initial observation of crops grown on these soils continually showed poor crop yield, general chlorosis and failure to respond to fertilizer additions. While not widely reported in the literature, these soils have been identified at sites in Idaho, Montana, Oregon, Utah and Wyoming. Their discovery suggests a need to further explore the distribution and origin of high extractable K soils. We may also be able to define steps to improve crop and livestock productivity on the sites. This paper presents what we know about excess-K soils and outlines current efforts to determine their origin, chemistry and impacts on crops and livestock

Identification and impact of excess soil potassium on crop and livestock nutrition

Several soils have been identified in the Intermountain West which contain excessive amounts of extractable potassium (K). A "normal" ammonium acetate extractable potassium level may be from 200 to 500 parts per million (ppm), while the high potassium soils contain 1,000 to over 7,000 ppm. Initial observation of crops grown on these soils continually showed poor crop yield, general chlorosis and failure to respond to fertilizer additions. While not widely reported in the literature, these soils have been identified at sites in Idaho, Montana, Oregon, Utah and Wyoming. Their discovery suggests a need to further explore the distribution and origin of high extractable K soils. We may also be able to define steps to improve crop and livestock productivity on the sites. This paper presents what we know about excess-K soils and outlines current efforts to determine their origin, chemistry and impacts on crops and livestock