Just as taking good-quality soil samples is important for making nutrient application recommendations, so is managing application rates and distribution of dry nutrients and lime. This also holds true for spring applications of urea, anhydrous ammonia applications and applications of solid and liquid manure.

Here’s what you need to know about dry fertilizer application.

Why streaks occur

Underapplication of dry fertilizer or lime that does not meet the required application rate recommendation can often negatively impact crop yields. Overapplication of nutrients can cause excessive input costs.

These misapplications can be caused by uneven nutrient distribution. Often, we notice underapplication in fields when we see “yellowish” repeating streaks in the field, usually in the spring.

Distribution issues are more evident with more widespread adoption of aerial imagery with drones. This issue is more important with nitrogen applications than with phosphorus, potassium or lime, but all are crucial for crop production. N and sulfur streaks in fields are the most noticeable. You will rarely notice symptoms of overapplication in the field.

What causes uneven distribution?

Many factors lead to uneven distribution of dry products. They include:

These factors should be addressed by the retailer for each product each year, and for major application rate changes and when product conditions change. For example, product form can change when you get to the bottom of the fertilizer pile and there is more product with a smaller size. Or, shape can change as product is constantly scooped, pushed and loaded. These instances can produce more fines that reduce the width of spread patterns.

Here are some ways retailers can improve dry fertilizer distribution:

What can farmers do?

Farmers rarely apply dry fertilizers and rely on their agricultural service providers for such applications. Communication is key to alleviating future issues. Here’s what to do.

Good fertilizer application and distribution is important to minimize yield loss in the field. Calibration and product quality evaluation help to identify where adjustments can be made to maximize return on investment for your fertilizer dollars.

Additional resources

For more information on how to improve dry fertilizer application, check out these links: