Ag Equipment

Todd Taylor of John Deere spoke to us yesterday about Nutrient Management from the Ag Equipment Perspective.  He discussion was actually quite generic when it came to "Big Iron".  He did discuss the positive effects of tillage regarding seedbed preparation and nutrient cycling.  His discussion went on to talk about 4R nutrient stewardship and the equipment that might help with getting nutrients to the right place at the right time.  He also talked a little about water management.

His discussion about electrical conductivity and using the Veris machine to make zone maps for soil sampling and nutrient application.  He also talked about soil pH manager and how it does a better job of mapping for lime than grid sampling does.  Both tools really point out that the grid a sampling that has been accepted as state of the art has weaknesses when we try to use the results in precision farming.  I have previously expressed my reservations about grid sampling as well.  The thing that the Veris and the Soil pH manager help people to do is to better define where the soil boundaries might be that affect crop production.

We overcome the weakness of grid sampling by trying to base our soil zones on the five factors of soil formation.  Many people who soil sample have not had the training to apply the five soil forming factors.  That is the reason for using some of the other tools mentioned.  One of those tools has been grid sampling.  Another tool that some mention is using soil survey maps.  The soil survey maps have weaknesses that I have previously discussed as well.  Those weakness are related to the scale of the original maps, the time allocated to do the work, and the quality of base maps especially aerial photos.   Perhaps I am biased because of my training, but I think I can make a good zone map that adequately characterizes the soil for precision applications by visually using the five factors and by using GPS to define the boundaries.  With any other method, in order to get the best maps, they should be evaluated by a trained professional and not just used as they come out of the "Machine".