Soil & Water Management

Agriculture today is not what it was a decade ago. We are at an interesting pace of agricultural technological innovation and development in sensors, controls, robotics and technology, including irrigation scheduling applications. The declining quantity and quality of freshwater resources in many parts of the world, including the United States, imposes significant challenges for producers, managers, advisors and decision-makers to produce more yield with less water. It is necessary to promote sound management strategies to improve irrigation efficiency and conserve water resources. By using irrigation scheduling applications, producers can make more informed decisions that can lead to higher yields with fewer irrigation inputs. Nebraska is one of the top states that produces maize under different irrigation methods, in third place after Iowa and Illinois. The total irrigated area in Nebraska reaches about 9.3 million acres. More than 85% of the total irrigation areas use the center pivot irrigation system, while about 15% is covered by furrow irrigation and less than 1% is managed by subsurface drip irrigation systems (see fig. 1). A new irrigation scheduling application is being developed to improve irrigation scheduling that can have a substantial impact in using limited water supplies more effectively and increase yield per unit applied of irrigation water and sustain agricultural productivity. At the request of Irriga Global, Lutry, Switzerland, a field test was initiated for the 2022 growing season on maize fields to evaluate the irrigation scheduling application in one of the Irrigation Today.

During the Soil Health School, presenters will cover many aspects of the science related to soil health, including foundational soil health principles, the evaluation of soil health management practices, and get to experience many hands-on soil health investigations and demonstrations. As a bit of a sneak preview, this article highlights what Leslie Johnson, Nebraska Extension Statewide Manure Educator will be sharing that day. Of course, she’ll be talking about how manure can impact soil health, but the role she’s the most excited about because it will be the most hands-on, is getting to show different ways of determining root growth.

Weekly Weather Update: June 8, 2023

This year’s 4Rs Field Day will focus on up-to-date research information and demonstrations on all three major crop nutrients: nitrogen, phosphorus and potassium.

The Soil Health Nexus is excited to debut two new resources on the Soil Health Toolbox! Two Soil Health Nexus members, Francisco Arriaga, Associate Professor and Extension Specialist at the University of Wisconsin-Madison, and Anna Cates, Assistant Professor and State Soil Health Specialist at the University of Minnesota, recently published a long-awaited whitepaper exploring the connection between soil health and water quality.

This UNL research study provides insights on the rotation of annual crops with alfalfa as a highly effective means of reducing nitrate-nitrogen contamination in groundwater.

For producers planning corn-on-corn this growing season, there may be a substantial opportunity to reduce nitrogen fertilizer applications, as drought and reduced yields likely left higher-than-normal residual N in many fields.

The nearly 70 on-farm research studies conducted by Nebraska farmers in 2022 addressed fertility and soil management, cover crops, crop protection, equipment and non-traditional products, including biologicals.

Results from 2022 variety trial research conducted on numerous cover crop species at five UNL research stations across Nebraska.

A new Nebraska Extension NebGuide clarifies the concept of consumptive use of water with regard to irrigated crop production and provides guidelines for determining the efficiency of new irrigation technology.

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.

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.

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.

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.

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.

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.

With silage harvest coming up quickly, manure application will soon follow. Because silage is often the first crop to come off the field, it allows for earlier manure application and thus an earlier cleanout of pens before winter. As that manure application plan develops, include best stewardship practices for optimum rates and preferred application methods in final decisions.

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.