This season, many climatic and soil factors are causing problems with corn and soybean growth. Sometimes plants also exhibit nutrient deficiency symptoms. A natural questions is whether the plants are actually nutrient deficient. If they are expressing deficiency symptoms, then yes they are. However, the reason may not be due to insufficient available nutrients in the soil, but rather poor uptake due to climatic or soil factors affecting growth. This was recently discussed in an ICM News article for potassium (K) in corn and soybean. If the symptoms are clearly present, then there really is no need for plant sampling and analysis as the plant is indicating the deficiency.
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