When it comes to naming the ultimate goals of no-tillers, getting the soils back to the original state Mother Nature intended would be darn near the top of the list.

And while every no-tiller thinks fertilizer is important, Jerry Mulliken of Nickerson, Neb., disagrees with the common practice of applying a uniform rate to an entire field. He says that an aerial photograph, a blank overhead transparency and a few markers, makes it possible to determine where the natural fertility areas of the fields lie. This inexpensive and relatively simple method, he says, sheds new light on effective fertilizer placement and the money that can be saved.

“The concept is that soil color is influenced by soil organic matter content, which is correlated to plant nutrient levels in the soil including nitrogen, phosphorus and zinc,” the crop consultant explains. “There is no one indicator of these nutrients, especially if fertilizer or manure has been applied. But there is quite a bit of scientific evidence indicating that organic matter is the best indicator of native fertility.”

How Do You Do It?

Actually, it’s surprisingly simple.

1. Using a blank overhead overlay or transparency and an aerial photo of the acreage you wish to assess, sketch the boundaries of the field and any distinctive features, such as waterways and terraces.
2. With the transparency over the photo, sketch in and number the management areas. The lighter color areas are likely to be lower in organic matter and the darker areas higher in organic matter…