Agronomy and Horticulture Department
Influence of burning and grazing management practices on subirrigated Sandhill meadow hay production
First Advisor
Mitchell Stephenson
Second Advisor
Jerry Volesky
Date of this Version
12-2020
Abstract
Subirrigated meadows are a valuable forage resource to Sandhills ranching operations being used for hay production, grazing, or a combination of both. Practices that sustain meadow productivity should be encouraged to ensure a consistent feed supply for cattle. The potential influence of prescribed burning or pre-freeze and post-freeze grazing on forage production and quality are not well understood on these meadows. In grasslands, including meadows, excess dead plant material can accumulate, causing a potential reduction in forage yield and quality. Results of our three-year field study suggest that burning meadows in the spring is a suitable management option to remove dead plant material without negatively affecting future hay production. Additionally, when burning was followed by either grazing exclusion or grazing from early-May to early-June, grazing had a greater influence on end of season biomass, with no interacting effect of burning and grazing. Quality of warm-season grasses was increased slightly following burning, but most improvements in quality were minimal and were a result of spring grazing. Study two evaluates a common practice of grazing meadows in the fall (pre-freeze) and winter (post-freeze) months. In our study, grazing in the fall when vegetation was still green was detrimental to future graminoid production. Relative to pre-freeze grazing, postponing grazing until plant dormancy (post-freeze) returned higher yields of graminoids and total live plant biomass. Deterring meadows from grazing in the fall and winter (control) produced graminoid and total live biomass that was similar to post-freeze treatments. Relative to pre-freeze treatments, summer biomass of ungrazed controls were generally higher in graminoid biomass, while similar in total live biomass. Quality of subsequent year’s forage in pre-freeze treatments was significantly higher than the control or post-freeze treatments and met the total digestible nutrient requirement of lactating cows. Our studies show that tradeoffs in quantity and quality are common under any practice. Therefore individual management objectives should be considered when deciding if a practice is right for them.
Advisors: Mitchell Stephenson and Jerry Volesky
Included in
Agricultural Science Commons, Agriculture Commons, Agronomy and Crop Sciences Commons, Botany Commons, Horticulture Commons, Other Plant Sciences Commons, Plant Biology Commons
Comments
A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Agronomy, Under the Supervision of Professor Mitchell Stephenson And Professor Jerry Volesky. Lincoln, Nebraska: December, 2020
Copyright © 2020 Tara Harms