Big Farms and Flawless Fries Are Gulping Water in the Land of 10,000 Lakes
When Minnesota farmers cranked up their wells in a drought, they blew through state limits. Thirsty crops included corn, soybeans and perfect, fry-friendly potatoes.
THE DROUGHT THAT GRIPPED MINNESOTA in the summer of 2021 was one of the worst on record. Day after day a blazing sun shriveled leaves, dried up waterfalls and turned ponds to puddles.
In a state known for its 10,000 lakes, many people could do little except hope for rain.
But big farmers had another option. They cranked up their powerful irrigation wells, drenching their fields with so much water that they collectively pumped at least 6.1 billion gallons more groundwater than allowed under state permits. Nearly a third of the overuse happened on land affiliated with one company, R.D. Offutt Farms.
The water helped R.D. Offutt to achieve its objective of creating long, smooth potatoes that effortlessly sail through the slicers at frozen food processors so Americans could have one of their favorite foods: McDonald’s French fries.
It takes a lot of water to make a perfect fry.
By turning on the taps in the depths of drought, R.D. Offutt and other farmers in the state — where thousands of wells irrigate potatoes and other water-intensive crops like corn, soybeans and sugar beets — blew through limits designed to protect aquifers that supply drinking water to millions of people.
For some Minnesotans, it significantly worsened the drought’s effects. And it exposed how dependent much of the state has become on aquifers that are fragile and often poorly understood.
What does the Science say about Biochar and it’s effect on Irregation and Yields?
After reading the article in The New York Times The Oaktree decided to look at the top three most common crops in South Carolina, Corn, Cotton, and Soybeans
1. Corn
There have been a number of studies that have shown the benefits of biochar for improving crop yields and reducing the need for irrigation. For example, one study found that the addition of biochar to maize fields in Mexico increased yields by 15% and reduced the need for irrigation by 25%.
There are several other studies conducted around the world, and they all come to the same conclusion, Biochar reduces the need for irrigation and increases the yields.
2. Cotton
The excessive drought will bring an increased salinity to the soil, which will increase the stress on the crops, to reduce the stress, the University of Copenhagen and the Wageningen University in the Netherlands looked at the Effect of biochar addition and reduced irrigation regimes on growth, physiology and water use efficiency of cotton plants under salt stress.
The conclusion was:
We concluded from the experiment that both salt stress and reduced irrigation had an inhibitory effect on the growth and physiology of cotton plants. Salt stress increased WUEp and WUEy although it reduced gas exchange parameters, leaf area, chlorophyll content, plant water use, dry biomass, and yield of cotton plants. Meanwhile, salinity changed the source-sink relationship, causing a decrease in dry biomass allocated to the stems and an increase in dry biomass allocated to roots, bolls, and seed cotton, thus increasing the root-to-shoot ratio and harvest index. The biochar amendment effectively alleviated salt stress and improved gas exchange parameters and leaf area, resulting in lower dry biomass allocation ratio in the roots and higher dry biomass allocation ratio in the bolls, thus improving dry biomass and yield, leading to an increase in lint ginning out turn, harvest index and WUEy by 0.21%–28.69%, 5.07%–14.39% and 5.83%–32.44%, respectively.
3. Soybean
One study, published in the journal “Soil Science Society of America Journal” in 2018, found that biochar application increased the water-holding capacity of soil by 20%, which led to a 15% increase in soybean yield. The study also found that biochar application reduced the amount of water needed for irrigation by 10%.
There have been several other studies all coming to the same conclusion, Biochar reduces the need for irrigation and improves the yields.
Savings for the farmer
1. Irrigation comes with a cost and most likely it will increase in areas where the droughts become more frequent.The average irrigation cost per acre in the US on an annual basis is $200 to $600. The actual cost can vary depending on a number of factors, including the type of irrigation system used, the source of water, the crop being irrigated, and the local water rates.
Here are some of the factors that affect irrigation costs:
- Type of irrigation system: The most common types of irrigation systems in the US are sprinkler systems, drip systems, and center pivot systems. Sprinkler systems are the least expensive to install, but they are also the least efficient. Drip systems are the most efficient, but they are also the most expensive to install. Center pivot systems are a good compromise between efficiency and cost.
- Source of water: The cost of water can vary depending on the source. Groundwater is typically less expensive than surface water.
- Crop being irrigated: The amount of water needed to irrigate a crop can vary depending on the type of crop. For example, corn requires more water than wheat.
- Local water rates: The local water rates can vary depending on the municipality.
In general, a farmer can expect to apply between 1 and 10 tons of biochar per acre. However, some studies have shown that even smaller applications can be effective. For example, one study found that applying 500 pounds of biochar per acre improved the water-holding capacity of soil and increased the yield of soybeans by 10%.
This exact amount has to be determined by a soil expert after the soil has been tested.
Other savings
Besides the irrigation, the farmer will also be able to save money by reducing the need for limestone, chemical fertilizers, and other chemicals, especially if cover crops are being used. The biochar can last in soil for thousands of years. However, the benefits of biochar can diminish over time, so it may be necessary to reapply biochar every few years to maintain the desired benefits, Also this has to be determined by a soil expert.
Conclusion
Biochar will reduce the need for irrigation and has the potential to save the farmer money in several other areas, and also, depending on the soil and the crop increase the yield.
