Why might a soil test not identify a nutrient deficiency in a plant?

A soil test may not identify a nutrient deficiency in a plant primarily because the nutrient content can change after collection. Once a soil sample is taken, various environmental factors such as temperature, moisture, and microbial activity can influence the availability of nutrients. For instance, nutrients may become more or less soluble in the soil solution, making them unavailable to the plants at the time of testing. Furthermore, if the sample is not handled properly or if it is stored for an extended period before testing, the results may not accurately reflect the current nutrient availability in the soil, leading to potential misinterpretation regarding the plant's nutrient status. This dynamic nature of soil nutrient levels underscores the importance of not only soil testing but also considering the timing and conditions under which the sample was collected.