The year 2019 marked the 350th anniversary of discovering phosphorus, an element required for all life on Earth and an essential plant nutrient in crop production. Over the years, we have fallen in and out of love with phosphorus as a necessary crop input and an unwanted water pollutant. Through improved knowledge and technologies, we […]
1. The two accepted soil phosphorus tests in the North Central Region are the Olsen and Bray-P1 methods The Olsen (bicarbonate) method is the standard soil P test in the North Central region. This method was developed to work on soils with low and high pH. The Olsen method works well in precision soil sampling, […]
1. Calcium (Ca) is abundant in soils of the upper Midwest, northern Great Plains, and Canadian Prairies; calcium deficiency in agronomic crops is rare Calcium makes up about 3.6% of the Earth’s crust, and it is relatively abundant in agricultural soils across the region. In soils with pH greater than 6.0, Ca is the dominant […]
From time to time, moderate to severe droughts hit the Great Plains. Such is life in semi-arid climates. When a drought occurs, it is normal to find higher residual soil nitrate-nitrogen after harvest. Since the widespread adoption of soil testing in the 1970s, we have seen this phenomenon in all major drought years: 1988, 2002, […]