The Karlen Family Partnership ranch located ten miles north of Reliance, South Dakota. Their pasture is three quarters of a section with a small triangle added to the northwest corner of the pasture. It is divided by solid hot wires which run North to South, dividing the pasture into two 160 acre and two 80 acre areas (without the small triangle).

The tests would reveal the quality of forage by measuring crude protein, digestible organic matter, fecal nitrogen and fecal phosphorus. These numbers are combined with information concerning weather conditions, herd conditions, and herd characteristics in a computer program called Nut Bal. This program gives the pounds of dry matter a cow and calf would eat in a day. Multiply that number by the herd size to calculate an average total pounds of dry matter the herd consumes in a day.

The concept behind this is the more the forage quality falls the less the herd will consume. The intern took twelve fecal samples throughout the summer; however, more or less can be taken. This method is very accurate but time consuming. Most producers can accurately predict or use a standard percent of body weight that their herd will consume.

To determine how much forage was produced in each day's area the intern would use a clipping method. This year's forage production in a 0.96 square foot circle that is a fair representation of the area is clipped and weighed in grams after drying the grass out.

By using a 0.96 square foot circle, one can multiply the weight in grams by a hundred to arrive at a number in dry matter in pounds per acre. For example, a clipped area of grass that weighs 21 g is 2100 lbs. per acre of dry matter. Thus we know how many pounds per acre of dry matter are standing in that day's area.

Now that we are aware of how much production there is in an area and how much forage the herd will eat for that area in a day, the producer must decide how much of that forage he can allow the cattle to consume or that is available. We take one third of the pounds per acre production level to decide how much forage is available.

To continue the example, one third of 2100 lbs. per acre is 700 lbs. per acre. The herd has 700 lbs. in every acre to consume in one day in that area.

Let's say the herd is eating 7000 lbs. of dry matter in a day (which is slightly higher than the summer average). By dividing 7000 lbs. a day by 700 lbs. per acre, we arrive at 10 acres for that day. The cows need ten acres to graze one third of the standing forage in one day.

The producer measured acres by spacing posts sixty-six feet apart on the three evenly spaced cross-fences of a section. By doing this, each space between two posts represents two acres. If we count off five posts then there is ten acres, and on the fifth post we stretch the polywire for that day, thus setting the size of the paddock in acres for that day.