What is in this article?:
- The availability of moisture for peanuts is critical at key times in the growing season for maximum yield and to reduce stress that can affect both yield and quality.
- Without irrigation, during the past three years many growers across the peanut-producing belt in the U.S. simply couldn’t plant peanuts because of a lack of soil moisture.
Corrin Bowers in South Carolina came back to his father’s farm armed with a degree in engineering from the University of South Carolina and valuable industry experience with precision technology. He has helped develop a highly successful system of monitoring soil and plant moisture and applying irrigation water as needed.
“We use a program called TCH20 that is a combination of two older programs,” he says.
“We put sensors at 8, 16 and 24 inches in the soil. The system has a data logger that records 24 hours a day, seven days week. I can go to the field with my computer and hook it up to the data logger or as long as I have a clear line of sight I can do it with a radio connection.
“After the crop is planted, I go in every morning and get a histogram of what the water is doing. I can tell what the plant available water and soil moisture are each day. It’s a highly evolved computer program that allows me to be a better farmer — I know more about our crop than we used to know.
“We are now watering our crops based on when the plants really need water. It takes out all the guesswork of looking at a crop and trying to determine when to irrigate and when not to irrigate,” Bowers says.
Another system of irrigating peanuts was recently developed by former USDA-National Peanut Research Laboratory Scientist Wilson Faircloth. The system developed in Georgia and Texas is called primed acclimation.
It is the intentional but regulated use of mild stress to change plant water use. Faircloth says the concept is similar to someone getting a flu shot, which actually exposes them to a mild case of the flu. When they come in contact with the same flu virus, their body is prepared for it and knows how to fight it.
“With primed acclimation, you are exposing the plant to intentional, regulated drought stress so it changes the physiology of the plant and changes its growth habits, such as causing it to have deeper rooting,” Faircloth says.
The newest version of Irrigator Pro, the expert system developed to help producers make decisions about their operations, now includes the concept of primed acclimation as an option for irrigation management, plus many other changes.
How much benefit growers get from proper use of irrigation varies significantly from one farm to another and from one year to another.
In drought years, laced with intense heat and humidity, irrigation can make a 2,000 pound per acre difference in yield. In addition to the yield increase, having water can also significantly reduce the incidence of aflatoxin and diseases that can further cut peanut profitability.
Most growers agree that in years that are within 20 year norms in heat and rainfall, irrigation consistently increases yields by 1,000 pounds per acre.
“Irrigation is the key factor in sustaining farm incomes and minimizing weather associated risks,” Lamb says. “This is true not just for peanuts, but for the crops we rotate with as well.
“We need to expand and protect irrigated acres. That’s why programs such as the Alabama Irrigation Initiative (and similar programs) are vital to our future.”
Like so many growers across the Southeast and Virginia-Carolina belts, the Bowers has to contend with herbicide-resistant weeds, particularly glyphosate-resistant Palmer amaranth (pigweed).
In the past, growers dealt with virtually every weed problem with glyphosate pre-plant and an over the top early season application of the same material, plus one or two others to control the few grasses and weeds not adequately controlled by glyphosate.