“There’s quite a good correlation with DD60s on peanuts – you just have to make a few modifications. It’s very accurate and a very good correction factor for the profile board. It’s not a stand-alone method to predict maturity, but maybe with some other features built in, it very well could be.”

With peanuts, the cotton DD60 becomes a DD56, he says. The DD56 is a threshold, assuming that below 56 degrees F, a peanut plant is not engaged in high growth such as putting on flowers and pods

A DD56 would be calculated by adding the maximum and minimum temperature, divided by two, minus 56. You add up DD56s to determine the heat unit for a given period of time.

“The important part of this is that you have to add in the water. It doesn’t take just heat to mature a peanut – it also takes water, and you must have both together. It’s a pretty good tool for determining peanut maturity.”

This method was evaluated last year, and every variety tested peaked at 2,500 growing degree days, plus or minus eight to 10 growing degree days, depending on the variety, says Faircloth.

In July or August, when daytime temperatures are in excess of 95 degrees F and low temperatures at night are in the 70s, a peanut plant can accumulate about 15 growing degree days per day.

“We’ve got a lot more research to do with this, but it’s a great correction factor when you’re using the hull-scrape method. You can look at the distribution on your board, and then look at the heat accumulation and make a good determination.”