Growing high-yielding, quality peanuts is an environmentally sound venture, but it isn’t easy. To remain sustainable, new and better ways to cultivate peanut production must be developed and embraced to handle U.S. peanut production’s many challenges.
This is the third article of the of Southeast Farm Press series “Peanut: It’s Sustainable” series sponsored by AMVAC/Thimet. In this article, we’ll touch briefly on a few sustainability measurements in which peanut growers score well at but maybe can do better, and we’ll also show part of the structure that keeps peanut production sustainable on the farm.
One important indicator used to measure a crop’s sustainability is irrigation water use and quality.
A recent study by the United Nations Educational, Scientific, and Cultural Organization looked at the water ‘footprint’ of U.S.-grown nuts, and it separates the water footprint of a crop into Blue Water (surface and groundwater irrigation) and Grey Water (water needed to disperse pollutants, most notably nitrogen).
Peanut’s Blue and Grey water footprint is 4.7 gallons per ounce of shelled U.S. peanut, according to the study, and that divides out to 2.7 gallons per ounce of Blue Water and 2 gallons per ounce of Gray Water. This is much less water per ounce than any other nut, which is a big feather to show off in peanut’s sustainability cap. (The same data show it takes 80.4 gallons of Blue and Gray Water to produce one ounce of shelled almonds.)
The ability of U.S. peanut farmers to produce high yields per acre plays a major part in the efficient use of water compared to other sources of nut protein, said Marshall Lamb, research director at the USDA National Peanut Laboratory. Practices which improve yields also can improve water efficiency, but that coin has a flip side: things that lower yields can lower water-use efficiency.
An example of this is the effect crop rotation can have on peanut production. Peanut farmers have long known the benefits of a strict crop rotation. But if a grower chooses to shorten a peanut rotation, he won’t be able to irrigate himself out of the yield-dropping consequences of doing so, Lamb said.
Irrigation improves yields. Studies going back to 2001 at the peanut lab provide 16 years of irrigated versus nonirrigated replicated yields over six crop rotation sequences. The studies use Irigator Pro to schedule amount and timing of irrigation.
According to information presented by Lamb, in short, an irrigated three-year-out rotation yields about 6,000 pounds per acre. A rotation just one year out of peanut drops irrigated yield to about 4,200 pounds per acre. Continuous peanuts, drops irrigated yield expectation to 3,340 pounds per acre.
Applying the peanut lab data to the parameters of the UNESCO study, a continuous peanut-behind-peanut scenario takes 5.8 gallons of Blue and Grey Water to make one ounce of shelled U.S. peanuts. In a three-year-out rotation, one ounce of peanuts requires only 3.7 gallons of irrigation water and pollutant-dispersing water.
The University of Georgia Peanut Production guide says peanut requires in total about 23 inches of water for optimal production. In 2016 at Wes Porter’s research plots near Camilla, Ga, the weather station reported 25.80 inches of rain from May 11 until October 15, which means the peanut-heavy region received enough rainfall without irrigation, or supplemental water, to make high-yielding, quality peanuts – theoretically, that is.
Yields in 2016 for the region were no record-breakers and far from record in some case. Heat and drought affected production.
“It comes down to hitting the supplemental water at the right time and the right amount for the conditions you are seeing in that field each year, and that is why yields in 2016 were down,” said Porter, a UGA Extension irrigation specialist and agricultural engineer, adding that over-irrigating during wet or dry years can adversely affect profitability as well as irrigating at the wrong time during dry years.
There are many irrigation scheduling systems peanut growers can choose, from workable free systems to more advanced, sensor-based precise systems, he said.
“It is strongly suggested that producers implement some sort of irrigation scheduling strategy beyond a checkbook, or historical evapotranspiration replacement method. There are free methods such as PeanutFARM and IrrigatorPro that perform very well and do a great job at estimating irrigation timing and requirements. There can be additional benefits from employing more advanced methods that include sensors, in both wet and dry years,” Porter says in the production guide, and based on three years of data.
Porter estimates some sort of advanced scheduling system is used on a quarter of the irrigated peanut acres in Georgia. Plans are in the works to update the UGA Extension irrigation survey this year, Porter said, to get a better idea on the irrigation practices farmers are using. The last survey was conducted in 2008.
An important variable in sustainable, profitable crop production is the availability of real-time field information, or data collection. In this regard, one important tool has thus far eluded peanut production: a workable yield monitor, the initial device in which to build better-defined field maps to more precisely manage a field’s variability.
Porter is also a precision ag specialist and is working in conjunction with peers at other land-grant institutions and private industry to develop and fine-tune a yield monitoring system for peanuts. Testing for one system showed promise in limited on-farm trials last year, and plans are to expand the testing to more farms this fall. A peanut yield map maybe on the horizon sooner rather than later, he said.
How well a cultivated crop can improve or sustain soil health is highly considered when measuring the sustainability, or environmental footprint, of the crop. Soil conservation practices score high points. Peanut producers have embraced minimal tillage or no-till, conservation tillage, however, the yield-drag believed to go along with the practices seem too much to some growers. But full-on conservation tillage has short and certainly long-term positive impacts on profits and soil health in peanut fields, said Kris Balkcom, agronomist with the Alabama Cooperative Extension Service.
“Conservation tillage brings on a little different thought process, a few different planters, equipment and guidelines you need to follow to make it a success. To do that is really like a marriage. You have to be dedicated for a marriage to work. You have to put in the time and effort and that’s a lot like conservation tillage. You have to get your cover crop planted timely, get the right tools that we have now available to us to help us utilize conservation tillage to be affective and profitable,” he said.
Peanut growers, public peanut scientists, agricultural agents, consultants and agribusiness retailers and agronomist do work together for the common interest of keeping peanuts a sustainable venture. One example of this partnership is Peanut Rx, a disease index that evolved from what once was the tomato spotted wilt virus index. By considering crop inputs, varieties and cultural practices, growers can gauge and manage the risk they have to the many disease that can prevent the sustainable production of high-quality, edible peanuts and improve the efficiency and profitability of peanut production in field-by-field scenarios by using specific inputs wisely or using less or the right crop protectants.
Agribusiness retailers supporting something that might lead to peanut farmers using less of a crop protectant seems counterintuitive, but major product companies who provide the products do support it, said Bob Kemerait, UGA Extension plant pathologist.
As the Peanut Rx was developed, “I don’t know of any other example where companies stood back from only recommending aggressive programs and were willing to work with us (in Florida, Georgia and Alabama) to recommend the appropriate program based on risk … because they saw as do we that the growers have to be successful and sustainable as well. Now growers have to recognize, too, that the cheapest program or product on the market may not be what keeps him sustainable,” Kemerait said.
To the Tables
Peanut farmers can be the most sustainable producers in the world, but if consumers don’t want to eat peanuts, it doesn’t matter. They’re opinions and buying habits impact the sustainability of peanuts on the farm, too.
“It’s important for us to communicate with consumers so they will understand how peanuts standout in sustainability among other choices that they have. Consumers are very interested where their food comes from today, especially millennials. They want to know how it was produced, who produced it and how sustainable it is and how that production affects the environment. We try to communicate that with peanuts because we know we have such a great story to tell and hopefully with that information, consumers will want to eat more peanuts and that will help make peanuts even more economically sustainable to produce,” said Bob Parker, president and CEO of the National Peanut Board.
The peanut reach through the U.S. and global food chain is considerable, but its acreage footprint is rather small and its farmers fewer when compared to other commodities that comprise the U.S. agriculture landscape. This can be seen as a liability, and maybe it is on some fronts. But that perceivably small status has proven to be an asset in many ways, too.
The peanut research and educational structure makes for tight, but competitive, partnerships between land-grant and federal institutions across the peanut belt, dedicated industry product development, representative groups and farmers. The choices each of these entities make and the directions they take, along with peanut’s image to consumers, will have a profound and direct impact on how sustainable and economical peanut production on the farm can remain now and in the future.