April's Ag Advice By April Borders Spring is approaching and cool-season grass pasture will soon be greening up and should be fertilized. Grass growth is stimulated by nitrogen fertilizer just like other crops. The key to profitable fertilizing of pastures is to combine fertilizer with efficient harvest of the extra growth.
If you fertilize pasture in the spring and then let animals graze continuously on that one pasture throughout the season, most of the extra growth is wasted. They trample some of the grass, foul some of the grass, bed down on some of the grass and simply refuse to eat some of the grass. Eventually, less than one-third of the grass produced will end up in the mouth and stomach of your livestock.
To make fertilizer pay, manage grazing so more of what you grow actually gets eaten. This will happen if you subdivide pastures with some cross-fences and control when and where your animals graze. Give animals access to no more than one-fourth of your pasture at a time, and preferably less. Then graze off about one-half of the growth before moving to another subdivision.
Another step is to time fertilization to stimulate grass growth when you need it. In spring many pastures grow faster than they can be used. So why fertilize everything in early spring to grow even more grass at that time? Instead, fertilize some pastures now and then wait until mid-May to fertilize some others for extra summer growth. And if it happens to be dry, you can save your fertilizer dollars since they will do little good without rain.
Another thing that I wanted to up date producers on is the prospect for leaf rust and stripe rust on wheat. Dr. Draper, Extension plant pathologist, recently sent us an update of the wheat rusts. Leaf rust appears to be at the heaviest level in the south than it has been in many years. Leaf rust is being reported in Louisiana (heavy), Texas (locally heavy, especially in the north central and south east), Oklahoma, (heavy in the south central and south west), and Nebraska has reported an overwintering population in the south central section of their state.
Stripe rust is not present at as high as is being seen with leaf rust, but is nonetheless quite common. Louisiana reports locations where both leaf rust and stripe rust are co-existing at high severity. Okalahoma is reporting heavy stripe rust on susceptible varieties.
It is our recommendation that producers need to be scouting and should be ready to treat if the disease is imminent. Research from Kansas State University indicates that 25 percent leaf rust severity on the flag leaf at flowering can result in a 15 percent yield loss. With the current rust situation to the south, producers should pay close attention to rust development in their fields prior to flowering. Stripe rust comes on early enough that waiting to treat at heading, as we do with scab, does not provide adequate control for stripe rust.
For more information on pastures or on rusts in wheat, contact the Clay County Cooperative Extension Office or call 677-7111.