Understanding Rest-Recovery for Native Prairie to Improve Grassland and Animal Productivity

Background

Preserving the remaining endangered native prairies in Canada is a priority for all stakeholders, though the ones who are largely tasked with this endeavor are Canadian farmers and ranchers. Land prices and feed costs continue to skyrocket, while there is financial gain in most cases for converting this native prairie to crop production or for other developments, we could do ourselves a favor by understanding how to best use these lands to graze cattle. Little is known as to how to maximize the productivity of these lands to support grazing animals and uphold the ecological goods and services they provide. If native prairie could be maximized without breaking ground, they could provide more value back to the producer in the form of animal performance.

The purpose of this study is to determine how stocking rate and grazing duration impact forage production, livestock performance and economics to identify the best rest-recovery times for native grasslands. This project builds on a previously funded Beef Cluster Project (evaluating the effects of stocking rate and grazing duration on the soil microbiome, carbon storage, soil greenhouse gas (GHG) emissions and soil-plat feedback). This will help to better understand the impacts grazing management strategies have on native grasslands as well as livestock and forage production.

Objectives

• Improve the management and productivity of native/naturalized pastures to enhance profitability and discourage land conversion.
• Better understand the impact of grazing management on plant, animal, and soil interactions and how the overall system contributes to plant and animal health and productivity.
• Identify critical extension priorities to improve grazing management practices that optimize the productivity of native plant species.

What they will do

36 spring-born, fall-weaned steers will be used for a two-year grazing study at Kernen Prairie, a native grassland NE of Saskatoon, SK.  This site has previously been grazed for 25 years with low stocking rates and season-long grazing. A 36-ha area will be divided into nine paddocks and designated as either an ungrazed control or one of three treatments: 1) short-term grazing at a low stocking rate, 2) Short-term grazing at a high stocking rate, 3) continuous grazing at a low stocking rate. Short-term is defined as grazing for 30 days, while continuous grazing will last 90 days. 36 spring-born fall-weaned yearling steers will be doing the grazing. Stocking rate and grazing duration will be monitored and adjusted if necessary, depending on precipitation and environmental conditions.

Forage Productivity: Forage composition will be assessed every spring to capture the available composition and fall to capture the residual composition. Forage yield and quality will be collected pre-grazing, post-grazing and every 30 days throughout grazing to monitor the impact grazing has on forage productivity using 1/4m quadrats. Regrowth will be measured with exclusion cages. These parameters will be used to determine the forage response to grazing and the rest recovery times.

Animal Productivity: Steer performance, estimated dry matter intake (DMI), diet selection and grazing behaviour will be determined through the course of the trial. By collecting body weight (BW), ultrasound measurement of body-fat, fecal analysis (diet composition and estimate DMI), and monitoring movement and behaviour with GPS.

Economic Analysis: Pasture carrying capacity, livestock BW gain kg beef producer per hectare, kg DM produced per hectare along with estimation of a typical operation’s land use requirements and respective land costs of each grazing strategy will be used for an economic comparison of the three grazing strategies.

Implications

The proposed project will add critical animal-level data to fully understand the impact of grazing management on both cattle and native grassland productivity. This will be one of the first ever projects to link animal level data and grazing management with their impact on the soil microbiome, plant-soil feedback, and GHG emissions.

This project will provide base knowledge regarding stocking rate, grazing duration, and rest recovery times to provide producers with timely and accurate information as they are making decisions on how to manage their native grasslands. Better understanding how to maximize animal and forage production on these landscapes will not only benefit the producer, but aid in preserving these unbroken lands. Maximize production without having to break ground/add tame species.