If you grew up farming and paying attention to soils in much of Indiana, you knew a lot of the lower, darker, naturally poorly drained spots as Brookston soils. These were the soils that would have done the best this year. They're always productive if you can establish a crop without ponding or drowning out because they are very high in organic matter, and hold water to a fault. They are not good for building houses on because they don't offer a suitable place for installing a septic system.
Today there are far fewer acres of Brookston soil than there were a couple decades ago, according to soil scientists. A soil judging contest was recently held on the same farm where a contest was held eight years ago. A hole in the same part of the field then was called a Brookston soil. This year it was called a Treaty soil. The properties were essentially the same, but the name was different.
"What's happening is that soil scientists continue to more accurately define and separate one type of soil from another," says Gary Steinhardt, Purdue university Extension soil scientist. The soil hasn't changed –
soil scientists are just fine-tuning how they describe soils so they can more accurately group subsets of various soils together. Often the difference may be as narrow as how much silt a soil contains vs. another very similar soil.
The difference is likely more meaningful to soil scientists making recommendations on where to build houses, or what kind of septic system is needed, than it is to farmers. However, farmers who stay up on soils are making the distinction. Soils that they called Brookston soils a few years ago, now may be further subdivided into Treaty soils.
What the change does is help you know just a little bit better what kind of soil you can expect if someone says you have Treaty or Brookston soil, for example.
"There aren't that many acres of true Brookston soil left because soil scientists have split it into other classifications," Steinhardt concludes.