About Soil Imagery and Soil Darkness Mapping
Different imagery can be used to produce soil darkness maps which can be useful management zone data as darker soil commonly relatively consistently correlates to higher yield if the area of darker soil is well-drained (not associated with a a sink [area where water ponds]). Articles that discuss darker soil corresponding to higher yield can be accessed in the Soil darkness and correlation to yield link in the Main Menu of the Articles folder. Unlike yield prediction maps, the NIR band is not necessary to produce soil darkness maps which is an advantage because high resolution imagery with just the visible bands is commonly available for free. The work involved in producing a soil darkness map includes smoothing the data to remove the effects of rows and, if necessary, the effects of structures such as electrical installations. Maps should be produced to the extent of a particular field. To produce a more useful soil darkness map it is important to find the image that better shows soil darkness patterns (crop residue and wetness can have varying effects). The Soil darkness mapping examples PDF includes a comparison of different imagery of soil darkness, resulting soil darkness maps, and correlation to yield.