Soil & Water Management

A research paper by University of Nebraska–Lincoln scientists points to an innovative irrigation approach that offers promise to decrease water use while increasing producer profitability.

The main barriers to adoption of new technologies in irrigation include cost and ease of use. These scientific methods need to be cost-effective and feasible for farmers to adopt. Today, using soil water monitoring equipment provides the most effective method for farmers to make data-driven irrigation scheduling decisions to apply the minimal amount of water while achieving optimal yields. However, the costs in labor and equipment limit their use. So, research continues to focus on developing lower-cost methods to schedule irrigation that results in putting on just the right amount of water. Since producers do not have time to do detailed work with large amounts of data often generated using SIS methods, the automation of SIS methods would likely provide incentives to producers by saving their time and, simultaneously, reducing the irrigation applications and producing optimal crop yield.

The Platte River, then the North Platte River, and then the Sweetwater River were the series of water courses across Nebraska into Wyoming east of the continental divide for a pathway across the country that “followed the water.” This was the most traveled route across the continent for early trappers — the California, Mormon, Oregon, Overland and Pony Express trails. Over 400,000 people followed these trails to California, Oregon and Washington, bypassing the “Great American Desert”, not knowing that in the future — with irrigation water development — this area would be the breadbasket for the country.

When the Reclamation Act passed by Congress in 1902 and the United States Reclamation Service was created, studies were conducted to determine where water projects could be constructed. Initially, the Sweetwater River (Sweetwater Project) was considered to construct a dam at “Devils Gate” to provide irrigation water. However, insufficient flows in the river did not justify the construction of a dam. The Reclamation Service then determined that a dam would be constructed on the North Platte River in the Fremont Canyon approximately 47 miles southwest of Casper, Wyoming.

Cover crops are a proven method for increasing soil health by reducing soil erosion, increasing soil organic matter, and improving soil structure. Cover crops also have the potential to positively impact water quality by reducing nitrate leaching and nutrient runoff. While cover crops are growing in popularity in Nebraska, there are significant planting challenges. To address these challenges, interseeding has been proposed as an alternative planting method to increase cover crop success.

At the end of the season, a nitrate test can help determine whether the crop was under-, adequately or over-fertilized with nitrogen, resulting in the potential to significantly reduce input costs.

With the two consecutive dry seasons in 2021 and 2022, there is likely a considerable amount of unused nitrogen left in the soil, which could be used for the 2023 crop. With the higher fertilizer prices, such fertility adjustments for next crop can be profitable as well as environment friendly. So, it is recommended to test your soil and account for all sources of nutrients for the next crop.

Precipitation continued the trend of a general lack of moisture during the first month of fall. Our monthly statewide total came in at 27th driest and makes for the 12th driest three-month (July–September) period on record. At the start of October, nearly all of Nebraska is in a drought category, according to the U.S. Drought Monitor. Portions of the northeast and southwest are in exceptional drought (D4). Temperatures averaged above normal for September and quite a few new daily high temperature records were set, most in the triple digits. The October outlook doesn’t appear to have much relief in sight with a higher-than-average probability of the warmth and dryness to continue. Given the dryness, fire danger will be high particularly on windy days.

Some crop growers have always removed crop residue for animal feed and bedding. Crop residue removal should be done in such a way that it benefits the grower without negatively impacting the health and productivity of the soil as well as the environment.

In this two-day course, NU experts will be discussing the latest research on soil fertility, precision ag for nitrogen management, cover crop effects on soil, soil carbon sequestration and more.

According to study from Department of Natural Resources researchers, irrigation pivots stained with rust may indicate the absence of nitrate in the groundwater supplying the pivots. This information can potentially be used to help screen for areas for the potential absence of nitrate and, in an ideal world, could indicate areas at higher- or lower-risk for nitrate contamination before it becomes a problem.

Nebraska farmers and agronomists are set to present results of their 2022 on-farm research studies on cover crops, variable rate seeding, starter fertilizer, biological products, seed treatments, variable rate nitrogen management and more.