As of Oct. 5, 2009, El Nino was still present across the equatorial Pacific Ocean with sea surface temperatures at least 1°C above average and expected to strengthen, lasting through the winter. This increases our probability of having a cool, wet winter. Winter El Nino episodes feature a strong jet stream and storm track across the southern part of the United States as depicted in the figure.
Those of us who planted winter pasture this September are enjoying excellent pasture conditions with stocking rates of 400-600 pounds of beef per acre. This is likely the best fall you have seen since 1994. Winter pasture will continue to grow for a little while as we move into December. Once soil temperatures fall below 55-60°F, plant growth is seriously inhibited, and what you have is about all you will see until the soil begins to warm up again in the spring. As a rule of thumb, 90 percent of fall production occurs by December. This is a great time for you to estimate reserve herd days to see if you will be under- or overstocked for the next 90 days and adjust accordingly. For fallplanted small grains, you will have approximately 150 lbs per acre-inch of forage and need to figure on leaving a 3-inch stubble height. Our Reserve Herd Day Calculator will assist you with your calculations.
If you are understocked, then animal gain will be maximized for the fall period and range between 2-2.25 lbs of gain per head per day. If you are overstocked, plan to feed a little along the way or simply expect average daily gain to be slightly below 2 pounds.
Those of you who will be grazing livestock on dry grass have already had enough moisture this fall. Any additional moisture from December-February only decreases the quality and quantity of available standing forage. It is much easier to maintain a cow's body condition during a dry winter as the grass remains more upright and is "stronger." Increased humidity during the winter also adds to the chance of an animal being out of its thermal comfort zone, which reduces its performance. Unless you are grazing on native grass in good to excellent condition, there is a high probability you will be feeding hay a little sooner than normal or expect to lose a little more condition on your cows. Even if you are grazing on standing native grass in excellent condition, you might plan to feed a supplement high in energy after Jan. 1 to help maintain body condition on your cows.