Low Heat Units Protection Help Guide
Low Heat Units Protection provides coverage against a lack of heat during a growing season that can reduce yield and/or lead to high moisture content at harvest. The coverage pays based on the accumulated heat units between the planting date (or other date specified) and the end date of the coverage or the first killing freeze. The total number of accumulated heat units is then compared to number of heat units needed and if there is a shortfall, the payout will be made incrementally based on the size of the shortfall.
Location
To begin quoting, enter your location details into the “Location" text box and click the “Locate” button. You can enter city, city and state, county, county and state, zip code, or latitude and longitude to find your location. Next, click on the marker ( ) for the location you want to quote. This populates the “Selected Location” text with the weather station name, city and state you selected (the map will also center on your selected location). To select a different station, move click and drag the map to your desired location and click a new marker.
Dates
Start Date
Enter the date from which you want to begin calculating the total number of heat units.
Freeze Temperature
This is the temperature for a killing freeze that will stop crop maturation. Once a daily minimum temperature at your location is recorded that is equal to or below this value, no further heat units on or after that day are accumulated. The most common value chosen for this input is 28 degrees Fahrenheit.
End Date
The date on which heat units will stop accumulating (unless the freeze temperature specified has occurred prior to this date). This also determines the date on which the coverage will settle, meaning that payment will be made shortly after this date, but not before.
Heat Units
Select a Crop
Your crop selection is used to set the temperature thresholds for calculating heat units. If you don't find the crop you need in the list, select "Other" and adjust the Heat Unit Range as needed.
Heat Unit Range
These temperature values are used to calculate heat units. If you need to adjust these numbers, click the edit link and enter the values that should be used to calculate heat units.
Total Heat Units Needed
The number of heat units needed between the Start Accumulation Date and your crop reaching maturity. If the Start Accumulation Date is your planting date, then this is the total number of heat units needed from planting to maturity.
Coverage
Maximum Coverage per acre ($):
The amount that will be paid if the final number of heat units is below the Max Coverage Heat Unit Level.
Maximum Coverage Level (heat units):
The number of heat units below which your coverage will pay the Max Coverage per acre. This should be the level of heat units that will result in significant yield loss or drying costs.
Number of Acres:
The total acreage you would like to protect. By entering a total number of acres your quote will include a total premium and total coverage amount in addition to a per acre premium and per acre coverage amount. If no value is entered, one acre is used as a default.
Common Questions
How does Low Heat Units Protection work?
Low Heat Units Protection pays out for a shortage of warm weather over the growing season. Payout is based on the number of heat units (also known as GDDs or GDUs) from the beginning of the season to the first killing freeze (or the End Date, whichever comes first).
How does the number of days needed for maturity (for corn) relate to heat units?
For corn, the number of days needed to reach maturity can be roughly estimated using the following table:
This table is an estimation; it is recommended that you adjust to your specific seed type accordingly.
Do I need to submit any acreage reports?
No. There is no need to submit any paperwork for the number of acres planted. The coverage payout is determined by weather conditions. At the end of the coverage period payment is made automatically with no need for additional adjustment or paperwork.
How will you know if my crop actually reached maturity?
Because the coverage is based on the heat units accumulated at your specified location, there is no verification of maturity by an adjuster and no claims process. Based on the temperatures during the coverage period, the coverage determines how many heat units accumulated and calculates your payout accordingly.
What is the Heat Unit Range? How are my heat units calculated?
Heat Units are often commonly referred to as GDUs (Growing Degree Units) or GDDs (Growing Degree Days). For the purpose of this coverage, these are all the same. Heat Units for a given day are calculated by adding the maximum temperature for the day and the minimum temperature for the day, dividing by 2 and subtracting the Heat Unit Base Temperature. Also, the daily minimum and maximum temperature cannot be less than the Heat Unit Range Minimum Temperature or greater than the Heat Unit Range Maximum Temperature. If the daily temperature does exceed the Heat Unit Range, then that daily temperature value is replaced by the Heat Unit Range Temperature.
For example, for corn the Heat Unit Range Minimum Temperature (and also the Heat Unit Base Temperature) is 50 degrees F and the Heat Unit Range Maximum Temperature is 86 degrees F. So if the daily maximum temperature is 90 degrees, 86 is used in the calculation. If the daily minimum temperature is 47 degrees, 50 is used in the calculation. The following scenarios demonstrate how the heat unit calculation works:
1.) If the daily maximum temperature was 75 degrees F and the minimum temperature was 60 degrees F, then the heat unit accumulation would be ((75 + 60)/2) – 50, or 17.5 heat units.
2.) If the daily maximum temperature was 95 degrees F and the minimum temperature was 70 degrees F, then the heat unit accumulation would be ((86 + 70)/2) – 50, or 23 heat units. (shows the daily maximum temperature cap)
3.) If the daily maximum temperature was 65 degrees F and the minimum temperature was 40 degrees F, then the heat unit accumulation would be ((65 + 50)/2) – 50, or 7.5 heat units. (shows the daily minimum temperature cap)
This calculation method is the most commonly used in US agriculture for determining heat unit accumulation. It was first introduced by the National Oceanic and Atmospheric Administration as the “Modified Growing Degree Day” formula.
Examples
- Start Date: 7/21/2010
- Freeze Temperature: 28 degrees
- End Date: 10/1/2010
- Crop: Corn
- Heat Unit Range: 50 F - 86 F
- Total Heat Units Needed: 2,400 heat units
- Maximum Coverage: $100 payout per acre
- Maximum Coverage Level: 1,800 heat units
- 500 acres
Then your Total Heat Units Covered would be 2,400. If the heat units accumulated between 7/21/2010 and either the first occurrence of 28 degrees or 10/1/2010 is equal to or below 1,800, then you would receive the full payout of $100 per acre.
If at the end of your coverage period there are 2,100 heat units, then the payout would be $50 per acre (as 2,100 is half way between the Max Coverage Level and the Total Heat Units Covered).