Cell Grazing for Improved Pasture Management

Imagine the prairie covered by huge herds of grazing bison. They are constantly moving and constantly eating. Their population density is very high but they rarely graze the same ground for more than a couple of days before moving on. They efficiently utilize the plants that are available to them as they make their way across the grasslands.

It is under such conditions that most of our native grass species evolved. Those plants that thrived under such conditions are the ones that we are familiar with today. They are the species that best utilize our abundant sunlight, good soils and rainfall.

When grazing native or improved pastures, perhaps there would be wisdom in considering the historical grazing patterns under which the forages developed. One method of managing pastures that in many ways resembles the highly concentrated, ever-moving bison herds is cell grazing.

Cell grazing is a pasture management system that divides pastures into small cells that concentrate animals. The basic premise is to graze a cell intensively for a short period of time and then to move the animals to the next cell. Over the course of time, the animals would rotate through all of the paddocks (or cells) and begin the process again. Why is such a system of value?

Forage plants, such as grasses, go through various growth stages. During Stage I growth, a few tentative shoots produce leaves in order to gather the energy from sunshine so that the plant can convert carbon dioxide, water and nutrients from the soil into more plant. This is accomplished through photosynthesis. As the plant becomes better established and is producing enough energy to maintain itself, it moves into Stage II growth. During this second stage, there is slightly less nutritive value in the leaves but abundant production of new growth. This is usually the ideal stage for grazing the plant. If left uneaten, the plant will move into Stage III in which the energy is shifted away from foliage growth and into seed production.

The idea of cell grazing is centered on the growth stages of the grasses to be grazed. Proper timing of moves will enable the grass to produce at its maximum capacity (both for forage production and for energy value) for a longer period of time during the growing season. The timing of animal movement is based on the stage of the plant rather than the calendar. This means that more livestock can be grazed on the same amount of pasture.

There are critical factors that must be considered in a cell grazing system. These include water availability to the animals, the life cycles of the specific forages to be grazed, the cost and type of fencing and the time requirements for monitoring the pasture and moving the animals.

Cell grazing systems require more planning than most traditional grazing systems. Careful attention must be paid to stocking rates, fertilization, a period of rest for the plants, patterns of livestock movement, nutrient value of the forage and the impact of animal density on the particular forage varieties being managed. Mineral supplementation to offset any soil deficiencies may be necessary. It may also be necessary to invest in additional watering facilities as well as fencing. Most cell grazing systems utilize electric fencing as a low-cost and flexible method of dividing pastures.

Cell grazing provides the opportunity for better pasture quality due to the intensive management based on the forage life cycle. It also allows for better utilization of the available forage so that more pounds of beef can be produced on the same amount of land.

This is a great time to evaluate your grazing practices for the coming year. Whether a cell-grazing system is right for a particular operation is something that must be determined by each individual. Whatever the decision, the planning and evaluating process should be beneficial.

Prescribed Burning for Rangeland

Extremely low humidity, dry conditions and an abundance of grass from excellent summer rains have created conditions of high fire risk in our area. Besides the risk to property and to life, wildfires can potentially damage pastures.

Fire was one of the principal forces that formed and maintained the Great Plains grasslands. Before European settlement of the plains, fires were generally set by lightening or by Indians. Unchecked, the fires typically burned extensive acreages before encountering natural barriers such as streams or green vegetation. Such fires helped to suppress the growth of woody plants and cacti.

In the 1960’s range managers began to examine the use of fire as a tool for manipulating plant communities. They saw prescribed burning as a way to rid pastures of invasive species and as a way to rejuvenate grasslands that had become overburdened with old growth. In studying the use of fire as a management tool, it was found that the timing of the fires was critical in achieving the desired results. Burning at the wrong time of year can in fact damage beneficial species, exacerbate erosion by wind and water, and create opportunities for invasive species to enter.

Prescribed burning has gained credence as a management tool for pastureland in recent years. It has been used extensively in the Flint Hills of Kansas since the 1880’s when it was found that steer weight gains increased on burned areas. It was not until recently however that the reasons for the increased gains were understood. Removing the old-growth overburden allowed tender new shoots to become readily available to the grazing cattle. These new shoots were both higher in nutritive value and more palatable. Other benefits included increased grass yield and suppression of woody species.

In short-grass species such as blue grama, black grama, and buffalograss that are common to our area, there is typically little benefit to burning. Such grasses do not form the heavy overburden of dried stems that are common in mid-height and tall grasses. In short-grass pastures, burning can be used to control invasive weeds such as kochia and Russian thistle. Timing of such burning is critical. Due to the typical low humidity, dry soil conditions and wind, burning at the wrong time may cause heavy erosion and general degradation of the pasture.

It has been found that prescribed burns should be conducted on entire pastures rather than spot-burning. This is because the new growth in burned areas attracts cattle and is typically overgrazed while unburned areas are underutilized. The result is damage to the grasses in the burned areas and establishment of invasive species in unburned areas. This brings us back to fire damage to pastures.

Many of the grass fires during the winter months are due to careless burning of trash or from cigarettes thrown out the windows of vehicles. They typically are suppressed before burning large areas. This results in a “patchy” burn across pasture. When the new spring growth occurs, these burned areas are typically the first areas in which the new grasses are visible and available for grazing. The shoots are tender and free of dried stems from the previous season. Cattle gravitate to such areas in the pasture and not only keep the grass cropped extremely short, their hooves damage the new shoots and destroy many plants. This causes bare areas in which invasive weed species may become established.

The best way to manage such problems is to prevent them from happening. It is a good idea to keep roadside areas free of heavy growth during seasons of high fire risk. Reducing the available fuel supply can prevent wildfires from occurring because there is no fuel to sustain them. If however, you experience accidental fire damage to your pasture, consider a controlled burn in the spring to reduce the potential damage from overgrazing of the spot-burn. Burning the entire pasture can rejuvenate the grasses, reduce many unwanted species and stimulate new growth. If you have burned areas, or use prescribed burning, make certain that you hold off grazing until sufficient growth has occurred to prevent damage by the cattle.

Prescribed burning is an excellent management tool when used properly. Wildfire is not. Prevent range fires by taking steps to reduce your risk.

Fall Forage Tips from Purdue

Fall forage tips from Purdue University:

Agronomist: Stunted pastures need growth spurt before grazing

WEST LAFAYETTE, Ind. - Many Indiana pastures could use a "Keep off the grass" sign.
Pastures that were battered by an April freeze, a hot, dry summer and potato leafhopper feeding might not be ready for livestock, said Keith Johnson, a Purdue University Extension forage specialist.

"In those areas where rain has fallen after it has been extremely dry, I would suggest producers...(complete article here).

Many factors influence the value of forage in late summer and early fall. These include drought, summer grazing pressure, insects, and freeze. This article addresses many of those issues and how to make the most of your forage.