Academic literature on the topic 'Wheat – Irrigation – Kansas'

Abstract. Residual soil water after harvest and prior to planting was measured to a depth of 2.4 m with neutron attenuation techniques for approximately 45 irrigated corn and 45 dryland wheat fields annually from 2010 through 2012 in the western one-third of Kansas. The sampling locations were in three-county transects in northwest, west central and southwest Kansas with generally five fields for each crop type for each county. Residual plant available soil water (PASW) in corn fields was generally much greater than in wheat fields (150%-160% greater) for any given sampling period illustrating the residual influence of irrigation. Although weather conditions varied between regions and years there was not a strong effect on PASW in irrigated corn fields but there was an effect in dryland wheat fields. Annual differences in fall irrigated corn PASW for the 21 individual fields that were available for sampling in all three years varied less than 50 mm/2.4 m soil profile implying considerable stability in an individual producer’s response (irrigation management and irrigation system capacity) to changing weather conditions as evidenced by the similar year-to-year PASW values. Drought conditions existed for much of the total period (fall 2010 through fall 2012) in southwest Kansas, yet the irrigated corn PASW was still relatively high (PASW value at approximately 62% of water stored at field capacity in a 2.4 m profile). So, the presence of drought may not be a good indicator of the amounts of residual soil water producers are leaving after irrigated corn harvest. Although differences in irrigated corn PASW varied greatly among producers (183% to 722% within a region), there were much smaller differences between regions and years with a variation from 8% to 22%. Irrigation system capacity (flowrate/area) had very little effect on residual fall PASW in the corn fields possibly indicating that producers with deficit capacity are pumping earlier and later into the season to help mitigate their lower irrigation capacity. Irrigated corn grain yields began to plateau when PASW reached a value of approximately 200 mm/2.4 m profile which would represent a water storage of approximately 56% of field capacity. The residual PASW in irrigated corn fields decreased about 1 mm for each 2 mm decrease in irrigation and cropping season precipitation illustrating the difficulties that can arise in managing for a target residual PASW. These results suggest that producers should be scheduling irrigation with science-based methods, rather than habits and previous experiences. Keywords: Corn, Field capacity, Soil moisture content, Soil water, Volumetric water content, Wheat.

Abstract. Selection of optimal crops and cropping systems for most efficient water use specific for local environments can improve global water security. Limited irrigation with ground water is one alternative to alleviate crops from low amount or unevenly distributed water in the growing seasons in semi-arid regions. The main objectives of this research were to quantify yield-water use relationships of three limited irrigated crops, determine effect of crop selection on profitability with limited irrigation, and identify profitable and alternative crop production systems. A field study was conducted at the Kansas State University Southwest Research-Extension Center near Tribune, Kansas, from 2012 through 2017. There were four treatments in the study, two 1-yr systems of continuous corn ( L.) (C-C) and continuous grain sorghum (L.) (GS-GS) and two 2-yr rotations of corn-grain sorghum (C-GS) and corn-winter wheat ( L.) (C-W). Overall corn yield after wheat (C-W) was about 1.4 Mg (ha)-1 greater than C-C. Corn and sorghum yields were similar grown as monoculture or in rotation with each other. Available soil water at corn planting and during the growing season were 20 to 40 mm (240 cm profile-1) less in the C-GS rotation compared with C-C and C-W rotations. Corn yield increased as water use (yield-water use) increased in C-W rotation but yield-water use relationships tended to be negative in C-C and C-GS rotations. Grain sorghum yield increased with water use in both rotations but at a greater rate in GS-GS compared with C-GS. Despite greater corn grain yield in C-W, our economic analysis showed that wheat was the least profitable of the three crops causing the C-W rotation to be least profitable. In this study, the most profitable limited irrigation crop rotation was corn-grain sorghum (C-GS). Keywords: Corn-sorghum-wheat, Crop rotation, Limited irrigation, Profitability, Supplementary irrigation, Sustainability.

Four cover crops {alfalfa (Medicago sativa L. `Kansas Common'), hairy vetch (Vicia villosa Roth), Austrian winter pea [Pisum sativum subsp. arvense (L.) Poir], and winter wheat (Triticum aestivum L. `Tam 107')}, alone and in combination with feedlot beef manure at 5 t·ha–1 were evaluated for 2 years to determine whether sufficient N could be supplied solely by winter cover cropping and manure application to produce high-quality muskmelons (Cucumis melo L. `Magnum 45') in an intensive production system using plastic mulch and drip irrigation. Among the legumes, hairy vetch produced the most biomass (8.9 t·ha–1) and accumulated the most N (247 kg·ha–1). Winter wheat produced more biomass (9.8 t·ha–1) than any of the legumes but accumulated the least N (87 kg·ha–1). Melon yields produced using legume cover crops alone were similar to those receiving synthetic N fertilizer at 70 or 100 kg·ha–1. Melons produced on plots with cover crops combined with beef manure did not differ significantly in yield from those produced on plots with only cover crops. Legume cover crops alone, used with plastic mulch and drip irrigation, provided sufficient N for the production of high-quality muskmelons.

In the Fall 1999 semester, the Department of Horticulture, Forestry, and Recreation Resources at Kansas State University introduced a 3-credit-hour irrigation system principles and installation course with experiential learning as the core of the instructional format. The experiential learning component of the course is the multiweek installation of a residential irrigation system during the laboratory sections that allows students to learn the procedural skills necessary to properly install an irrigation system. To assess the influence that this experiential learning activity may have on students' confidence to perform specific irrigation installation skills, a survey was administered to 70 undergraduates enrolled in the course (HORT 550: Landscape Irrigation Systems) during the Fall 2006 and 2007 semesters before and after the completion of the irrigation system. Using a Likert scale, students responded to two questions pertaining to 10 specific irrigation skills used during the installation project: 1) whether they actually performed the particular skill during the installation (coded 0 = did not assist, 1 = did assist); and 2) how confident they were to perform that aspect of installation on their own (on a 9-point Likert scale with 1 = not at all confident to 9 = extremely confident). The correlation between whether students actually performed the particular skill during the installation and how confident they were that they could actually do it on their own was significant (r = 0.46, P < 0.0001). During the Fall 2006 semester, 44 students were asked to compare their actual experience installing the system to what they learned during lecture and by reading the textbook; participants said that installing the system greatly increased their understanding (mean = 7.84, sd = 1.41) and increased their confidence to perform particular skills (m = 7.84, sd = 1.03). As documented in the survey, students benefitted significantly from this experiential learning activity.

Highlights Irrigation is key to the productivity of Great Plains agriculture but is threatened by water scarcity. The irrigated area grew to &gt;9 million ha since 1870, mostly since 1950, but is likely to decline. Changes in climate, water availability, irrigated area, and policy will affect productivity. Adaptation and innovation, hallmarks of Great Plains populations, will ensure future success. Abstract. Motivated by the need for sustainable water management and technology for next-generation crop production, the future of irrigation on the U.S. Great Plains was examined through the lenses of past changes in water supply, historical changes in irrigated area, and innovations in irrigation technology, management, and agronomy. We analyzed the history of irrigated agriculture through the 1900s to the present day. We focused particularly on the efficiency and water productivity of irrigation systems (application efficiency, crop water productivity, and irrigation water use productivity) as a connection between water resource management and agricultural production. Technology innovations have greatly increased the efficiency of water application, the productivity of water use, and the agricultural productivity of the Great Plains. We also examined the changes in water stored in the High Plains aquifer, which is the region’s principle supply for irrigation water. Relative to other states, the aquifer has been less impacted in Nebraska, despite large increases in irrigated area. Greatly increased irrigation efficiency has played a role in this, but so have regulations and the recharge to the aquifer from the Nebraska Sand Hills and from rivers crossing the state. The outlook for irrigation is less positive in western Kansas, eastern Colorado, and the Oklahoma and Texas Panhandles. The aquifer in these regions is recharged at rates much less than current pumping, and the aquifer is declining as a result. Improvements in irrigation technology and management plus changes in crops grown have made irrigation ever more efficient and allowed irrigation to continue. There is good reason to expect that future research and development efforts by federal and state researchers, extension specialists, and industry, often in concert, will continue to improve the efficiency and productivity of irrigated agriculture. Public policy changes will also play a role in regulating consumption and motivating on-farm efficiency improvements. Water supplies, while finite, will be stretched much further than projected by some who look only at past rates of consumption. Thus, irrigation will continue to be important economically for an extended period. Sustaining irrigation is crucial to sustained productivity of the Great Plains “bread basket” because on average irrigation doubles the efficiency with which water is turned into crop yields compared with what can be attained in this region with precipitation alone. Lessons learned from the Great Plains are relevant to irrigation in semi-arid and subhumid areas worldwide. Keywords: Center pivot, Crop water productivity, History, Sprinkler irrigation, Subsurface drip irrigation, Water use efficiency.