ABSTRACT
A comparison was conducted between Strong Bray, Mehlich 3 and Olsen's P extractants on a Norwood silt loam (Fine silty, mixed, calcareous, thermic Typic Udifluent) to determine which extractant was most correct in recommending fertilizer P. Soil test P levels varied greatly across the years tested. Strong Bray correctly recommended P fertilizer two of three years tested. Olsen's correctly recommended P fertilizer one of three years. Mehlich 3 incorrectly recommended P fertilizer all three years. However, the Mehlich 3 incorrect recommendations may be the result of recommending P fertilizers as a small maintenance amount. In all cases of incorrect recommendations, the methods recommended fertilizer where no yield response occurred. In no case did any method under-recommend P fertilizer.
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