Soil Resource Assessment To guide production practices

1. Soil Resource Assessment To guide production practices Newell Kitchen USDA-ARS Cropping Systems and Water Quality Research Unit Columbia, MO Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, 10-11 October 2012, Columbia, MO

2. 1803 Louisiana Purchase and in 1804 a treaty between U.S. Government and Indian tribes (ignored by many Indians for several decades) • 1820-30s Land purchase and settlement exploded with most of the public land purchased within these decades. • 1850-1880 Railroads accelerated growth and commercialization

3. With early homesteading, timber was an essential resource used for homes and sheds, tools, cooking, and heating. Thus, most homes were near streams. • The broad flat grassland was viewed less valuable and was mainly used for free-roam grazing for many decades. • Early in the 1900s the face of the Midwest rural landscape • Farms increased in size • People migrated to cities • Agricultural mechanization improved

4. Extensive flat grasslands were plowed and put into grain production for the first time, typically corn, oats, wheat and a new crop, soybean. • During World War I, corn grain prices soared, and so did corn acreage. • This major shift in land use and intensity in the early 1900’s had an immediate impact on the rivers and streams

5. With the exception of two years, multiple and damaging large flood events caused severe soil erosion and property damage between 1926-1936. Grain crop yields for many fields actually declined when compared to the previous century (Bennett, 1939). • Since, billions of dollars have been spent on soil and water conservation projects. But with some soils, the damage has been catastrophic and irreparable.

6. Where in the Midwest was the negative impact of modern agriculture the greatest? The first erosion plot research in the U.S. was established on the campus of University of Missouri-Columbia, on May 1, 1917.

7. Cascading Soil Degradation Poor Land Management Decisions on Sensitive Soil Landscapes Degraded structure & aggregation Compaction & crusting Water erosion Reduced plant growth Poor soil biology Decreased yield Reduced Sustainability

8. 1. Lost Topsoil. In less than 150 years, claypan soils have greatly lost topsoil, and consequently other important qualities (e.g.,microbial diversity, structure). • Average 13 cm (5 in) of soil loss over the whole field. That averages ~7.5 tons/A/yr. • Areas of extreme have lost 40 cm (16 in).

9. 2. Historical topsoil loss from erosion has greatly impaired claypansoil field productivity, creating “marginal areas ” under some cropping.

10. 3. Soil quality and ecosystem function for claypan soils will not likely improve much under grain cropping practices.

11. 4.Claypan soils are especially good candidate fields for in-season variable-rate N management, because of the high propensity for denitrification losses.

12. 5. No-till corn-soybean on claypan soils often ends in failure and a return to tillage, because erosion persists. Adding cover crops with no-till is more successful.

13. 6. Depth to the claypan and slope are key soil properties for identifying marginal vulnerable areas within claypan soil fields.

14. 7. No-till cropping increases losses of runoff and soil active herbicides on claypan soils.

15. 8.Claypan soil fields exhibit strong spatial patterns of variability for soil properties and crop growth. Important factors include topsoil depth and past practices. Topsoil Depth Potassium Phosphorus pH

16. 9. The claypan drives surface hydrology and the environmental problems found on these fields. They behave as if they have much greater slope.

17. 10. Depth of topsoil over the claypan is a strong measure of soil erosion and serves as a useful basis for future crop management planning.