AUBURN, Ala.–Rapid technological advancement has become a staple in the field of agriculture. For decades, complex scientific discoveries have been the driving force behind ever-increasing yields. However, not all innovation stems from a chemical breakthrough. Pod blasting, a 20-year-old method to measure peanut maturity, is a simple process that requires nothing more than a pressure washer and a picker basket.
Kris Balkcom, Alabama Extension research associate and peanut specialist, recently walked through the process, offering both information and tips on the subject. For starters, pod blasting comes with some big advantages. “It’s a lot faster and easier,” Balkcom said. “You get a better idea of maturity from a higher percentage of the crop.”
The quickest way to determine if a peanut crop is mature enough for harvest is to check the color of the pods. The darker the pods are, the closer they are to maturity. Farmers must remove the exocarp, or the outer shell, in order to find the color and measure maturity.
“We used to hull-scrape with a knife,” Balkcom explained. “When you do that, you’re looking at a handful of peanuts.” Additionally, removing each exocarp by hand was a tedious process. “Now, with pod blasting, we’re looking at 200 peanut pods at a time, easily.”
A breakdown of the pod blasting process
- The farmer gathers a representative sample of peanuts from the field, including at least five or six plants.
- The farmer removes the pods by hand from the plants. Also, no pods should be left in the ground. This collection process garners about 200 pods.
- All 200 pods are poured into a picker basket, and the basket is placed in a five-gallon bucket.
- The pods are sprayed with a lightweight pressure washer at 1300-1600 PSI. The sprayer should hold the pressure washer about a meter away from the pods to avoid destroying the pods. This ensures that the exocarps are removed without damaging the fruit.
- The naked pods are measured against a maturity board. The color coded board shows the farmer how many days remain until optimum harvest time. The darker the pods, the closer they are to maturity.
The main purpose of pod blasting is to invert peanuts at the best possible time. About 140 days after planting, the farmer turns over the peanuts in the field and leaves them to dry. If done before or after optimum maturity, farmers risk losing a significant portion of their crop. Jimmy Jones, Alabama extension agent, helped to quantify the advantages of pod blasting.
“If the farmer inverts their field a week early, they’ll lose 300-500 pounds of their crop,” Jones said. “If they’re a week late, they’ll lose at least 500 pounds, and probably more.”
This has some big financial implications. Peanuts can go for about 425 dollars a ton, and the higher the quality, the higher the price. “We have a 100-point grading system based on peanut quality,” Jones said, “and with pod blasting, we can gain the farmers about 3 points on the scale. The price rises about 8 dollars a point.” Furthermore, inverting at the right time ensures that the vines retain their vigor, which helps the peanuts into the machine.
Jones is the county extension coordinator in Henry County, and holds pod blasting workshops at the Wiregrass Research and Extension Center. From 8 am to 12 pm on Tuesdays and Fridays in September and October, he pod blasts peanut samples for farmers in the region. An extension agent for 29 years, he remembers the days before producers began using pod blasting
“We were still scraping the peanuts on the tailgate with the farmers back then,” Jones said. The hull-scraping process, he explained, took all day. In the early days of pod blasting, it would take 30 minutes just to run the sample.
“Now it takes me three minutes,” he said. “We can run as many as 50 farmers in a day.”
The main thing he emphasized with pod blasting was making sure that farmers hit the optimum harvest date. “If you miss, you should miss early,” he advised. “If you miss the date completely, it starts getting pretty drastic.” Harvesting before maturity can result in losses up to 500 pounds, but harvesting late will result in even greater losses. Of course, with pod blasting, farmers can now pinpoint their optimum harvest date within three to five days.
Ensuring the best results
The first round of pod blasting should begin about 125 days after planting. This year in Alabama, that date is about a week away. “You can look at the plants and tell–– when peanuts near maturity, they go from lush green to a more bronze color,” Balkcom said. “You should always pod-blast at least ten days before harvest time to make sure you aren’t overshooting.”
Balkcom also recommended checking different spots in the field, as well as pod blasting multiple times. Not all the peanuts have to be mature at the optimum inversion time, either–– sometimes, farmers have to invert their field while some of the pods are still growing, rather than risk losing a crop of already-mature peanuts. “You play the hand you’re dealt,” Balkcom said. Fortunately, the advent of pod blasting has made the process that much easier for peanut farmers throughout the state.
There is some new technology on the horizon. Jones said that he can envision a day when peanut farmers don’t have to sample at all. Already, cotton farmers check their optimum harvest date with a smartphone app by inputting conditions and crop variety, and there’s been some experimentation with this concept for peanuts.
For the time being, pod blasting remains the best way to maximize yields. “It’s a tried and true method,” said Jones, “and that’s what we’re going to continue to do.”