Sampling Philosophy

We  pull soil samples by management zones.  Zones can be determined a number of ways or a combination of ways.  Soil types can be a good place to start.  We like to use landscape position as a criteria.  Yield zones can sometimes show variability well.  Yields from several years that are normalized work best.  We like zones as apposed to grid sampling because a grid sample too small of an area, even if it represents only 2.5 acres.  In order for grid sampling to work, grids would need to be smaller than one acre.  That would be cost prohibitive.  Pulling plenty of cores per sample improves the representative nature of the sample. 
There are lots of ideas about how often to soil sample a field. Some say every four years is often enough. Some say every crop cycle. In other words, in a corn soybean rotation, every 2 years. Our service provides annual sampling. Why is that needed? It allows us to track your fertility every year. It allows us to monitor your field every year for other soil health issues that we may see. It also takes the guesswork out of how much fertilizer you need. You don't have to worry about how much last year's crop took off, or how much fertility is left. By having the data you know where your fertility levels are. Also, the more familiar we are with your fields the better we can advise you.