Corn producers in parts of the state are nearing the point in time where they are thinking about fungicide applications to their fields. In a recent post on my blog I discussed tar spot and also mentioned a recent publication that shows that a single fungicide application at the VT/R1 growth stage has the greatest chance of providing the producer with a return on their investment.

Nobody knows your farm history and yields better than you do. That is why running the numbers yourself and thinking about your past experiences can help you determine how likely you are to break even or make a profit using various programs under your specific situation.

To calculate how much yield needs to be protected to break even at a given application cost (fungicide cost plus application costs) and commodity price:

yield protected (bu/A) = application cost ($/A) / corn price ($/bu).

This formula can be used to help you determine the amount of protected yield and commodity price needed to break even and see a return on your investment.

For example, to see how much yield would need to be protected by a fungicide to pay for the cost of a  $26/ A total application cost at a $4.50 per bu grain price:

yield protected = ($26.00 per A )/ ($4.50 per bu) = 5.8 bu/ A

the same situation but a program that costs $30 per A =

($30.00 per A)/($4.50 per bu) = 6.7 bu per A. 

Below is a table of the potential protected yields needed to break even at a few different commodity prices and total application costs.

Application Cost                                                   Price (BU)

                 $3.50 $4.00 $4.50 $5.00 $5.50
$20 / A 5.1 bu 5 bu 4.4 bu 4 bu 3.6 bu
$25 / A 7.1 bu 6.3 bu 5.6 bu 5 bu 4.5 bu
$30 / A 8.6 bu 7.5 bu 6.7 bu 6 bu 5.5 bu
$35 / A 10 bu 8.8 bu 7.8 bu 7 bu 6.4 bu
$40 / A 11.4 bu 10 bu 8.9 bu 8 bu 7.3 bu


Knowing your application costs for one or two trips and product, and estimating the commodity price, what sort of yield response will you need? Have you seen this sort of yield response on your field before or not? Has this response been fairly consistent? Knowing this information can be very useful in selecting fungicide programs for your specific fields