The Bray P-1 extractant was developed before the Mehlich-1 extractant and was widely used by the Southeastern states. Even though it works well on acid soils, it is only useful for extracting phosphorus. Therefore, an additional extractant must be us ed for determining other plant nutrients such as potassium, calcium and magnesium. As the demand for soil testing increased and laboratory instrumentation improved, it became desirable to have an extractant that could be used for a wide range of plant nu trients, including the micronutrients. When the Mehlich-1 extractant was developed, many of the Southeastern states switched to the Mehlich-1 since it could be used as a single extractant for many plant nutrients of interest and not just for phosphorus l ike the Bray P-1. The only time the Bray P-1 is used on Southeastern soils is when the soil samples are analyzed by a private laboratory which also services farms from the Central region of the U.S. where the Bray P-1 soil extractant is still commonly us ed. The Southeastern Land Grant Universities have no current information for interpreting soil phosphorus levels using the Bray P-1 extractant so it is recommended that this extractant not be used.
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