What is a common practice when applying biosolids to meet nutrient recommendations?

Applying potash for potassium needs is a common practice when applying biosolids to meet nutrient recommendations because biosolids often vary in nutrient content. While they can provide substantial amounts of nitrogen and phosphorus, they may not provide adequate potassium levels, which is essential for plant growth and development.

In agricultural practices, ensuring a balanced nutrition profile is critical. Therefore, when biosolids are utilized, it's important to assess the specific nutrient requirements of the crops. If potassium is lacking, adding potash can help fulfill the plant's nutrient needs, promoting optimal growth and yield. This practice not only enhances the nutrient profile of the soil but also ensures that crops receive the necessary elements for healthy development.

The other options imply an incomplete or ineffective approach to nutrient management. Focusing only on nitrogen neglects the importance of other nutrients, while relying solely on natural fertilizers does not necessarily provide a well-rounded nutrient supply, especially if the natural sources lack key elements. Ignoring soil tests completely undermines the ability to tailor nutrient applications to specific field needs, increasing the risk of deficiency or over-application of nutrients.