If you want to fertilize a tree with 4 lbs of actual nitrogen using 16-4-8 fertilizer, how many pounds of fertilizer are needed annually?

To determine how many pounds of fertilizer are needed to provide 4 lbs of actual nitrogen using a 16-4-8 fertilizer, first, it's important to understand what the numbers in the fertilizer designation mean. The first number, 16, indicates that the fertilizer contains 16% nitrogen.

To calculate the amount of fertilizer required to achieve the desired nitrogen application, you can use the following formula:

1. Start by dividing the amount of nitrogen needed (4 lbs) by the percentage of nitrogen in the fertilizer (16% or 0.16). This calculation gives you:

[

\text{Amount of Fertilizer} = \frac{\text{Desired Nitrogen}}{\text{Nitrogen Percentage}} = \frac{4, \text{lbs}}{0.16} = 25, \text{lbs}

]

This means that you would need to apply 25 pounds of the 16-4-8 fertilizer to deliver the required 4 pounds of actual nitrogen to the tree.

Understanding how to interpret fertilizer labels and perform these calculations is key for proper tree care and ensuring that the trees receive the necessary nutrients for healthy growth. The selected answer correctly reflects that 25 lbs of the fertilizer will