Add to ORKGIowa State University (ISU) has provided soil-test interpretations for the Bray-1, Olsen, and Mehlich-3 (M3) soil phosphorus (P) tests since 1996. These tests use a colorimetric analysis method to measure the P extracted from the soil. This method is based on the intensity of a blue color that develops after adding appropriate chemicals to the soil extract. The M3 and Bray-1 P tests measure approximately the same amount of P in acid or neutral soils. However, the Bray-1 test measures less P than it should from some high-pH (calcareous) soils and is not recommended for soils with soil pH 7.4 or higher
Research during the past few years has shown that severe deficiencies of nitrogen (N) are common in ...
The recent heavy rains have raised questions about nitrogen (N) losses. In wet field areas it is com...
The wet weather presents several challenges to accomplishing fieldwork this season. Whether it is pl...
Iowa State University (ISU) potassium (K) soil-test interpretations and fertilizer recommendations w...
This year, some producers have already started to harvest in very dry soils, and their risk of soil ...
Growers and those who advise them receive annual prompting to consider collecting soil samples from ...
Every spring presents new challenges for producers in assessing and working with field and soil cond...
Much of the primary fertilizer nitrogen (N) for corn is applied in the spring as pre-plant or sidedr...
Corn ear rot problems are often related to how long the corn stands in the field in the fall, the am...
All soils contain calcium ions (Ca2+) and magnesium (Mg2+) cations (positively charged ions) attract...
There was a considerable amount of tillage activity during fall 2001 in different parts of the state...
The Iowa State University Plant Disease Clinic offers two different nematode analyses for soil sampl...
Soybean yield loss due to the soybean cyst nematode (SCN) occurred throughout much of Iowa in 2006. ...
Soil erosion is a major environmental issue because it can lead to water pollution. But did you know...
Establishing an even distribution of crop residue while harvesting is critical in stopping soil eros...
Research during the past few years has shown that severe deficiencies of nitrogen (N) are common in ...
The recent heavy rains have raised questions about nitrogen (N) losses. In wet field areas it is com...
The wet weather presents several challenges to accomplishing fieldwork this season. Whether it is pl...
Iowa State University (ISU) potassium (K) soil-test interpretations and fertilizer recommendations w...
This year, some producers have already started to harvest in very dry soils, and their risk of soil ...
Growers and those who advise them receive annual prompting to consider collecting soil samples from ...
Every spring presents new challenges for producers in assessing and working with field and soil cond...
Much of the primary fertilizer nitrogen (N) for corn is applied in the spring as pre-plant or sidedr...
Corn ear rot problems are often related to how long the corn stands in the field in the fall, the am...
All soils contain calcium ions (Ca2+) and magnesium (Mg2+) cations (positively charged ions) attract...
There was a considerable amount of tillage activity during fall 2001 in different parts of the state...
The Iowa State University Plant Disease Clinic offers two different nematode analyses for soil sampl...
Soybean yield loss due to the soybean cyst nematode (SCN) occurred throughout much of Iowa in 2006. ...
Soil erosion is a major environmental issue because it can lead to water pollution. But did you know...
Establishing an even distribution of crop residue while harvesting is critical in stopping soil eros...
Research during the past few years has shown that severe deficiencies of nitrogen (N) are common in ...
The recent heavy rains have raised questions about nitrogen (N) losses. In wet field areas it is com...
The wet weather presents several challenges to accomplishing fieldwork this season. Whether it is pl...