Introduction

In 1989, we initiated an ongoing grazing-intensity research project at Central Grasslands Research Extension Center, northwest of Streeter, North Dakota. The objectives of the project are to determine the effect of grazing intensity on cattle performance, profitability, and the sustainability of forage production. Five treatments are included in the study: no grazing, light, moderate, heavy, and extreme grazing. Each treatment is replicated three times in pastures of about 30 acres each except the no-grazing treatment, which consists of six 0.3-acre exclosures placed on both loamy and loamy overflow ecological sites. Livestock are not rotated between pastures and each pasture receives the same treatment each year. Our goal is to stock the pastures each year so when the cattle are removed in the fall, 65, 50, 35, and 20 percent of the forage produced in an average year remains on the light, moderate, heavy, and extreme treatments, respectively. For these pastures, that means 2129, 1698, 974, and 501 lbs./acre of forage remains on the light, moderate, heavy, and extreme pastures, respectively. Table 1 presents the stocking history of the study and Figure 1 shows how much forage remained at the end of the grazing season each year.

To attain the desired grazing intensities, adjustments in stocking pressure are made each year based on information from previous years. Changes in the vegetation are determined by monitoring permanent plots located on loamy and loamy overflow ecological sites in each pasture and the six exclosures. Table 2 lists the average production on these ecological sites during each year of the study and the total precipitation for the year.

Table of Contents

• Introduction
• Stocking Rate
• Livestock Response
• Effect of Grazing Intensity on Forage Production and Utilization, Soil Water and Forage Quality
• Plant Community Dynamics
• Recommendations