Tim and Tommy Colbert
Chester County, Tennessee
Brothers Tim and Tommy Colbert began farming near Jack’s Creek and Plainview, Tennessee in 1973. They constructed terraces in the 1970s and 1980s and now their entire headquarters farm is terraced and laid out on the contour to reduce gully and rill erosion.
Like most West Tennessee row-crop farmers, their main enterprise was cotton for three decades, even after adopting no-till over thirty years ago. About seven years ago, they began farming a rotation of cotton, corn, soybeans, and wheat. Today, their cropping enterprise spans about 1,700 acres, and as of 2015, no longer includes cotton.
Since adding diversity and higher residues to their rotation and no-till system, the brothers have seen increases in soil organic matter (SOM) on all of their silt loam fields. Ten years ago, their SOM was at 1 percent on average. In 2015, their fields measured between 2.2 percent and 4 percent SOM. Their soil structure still has some weak platy structure, but roots penetrate it readily and earthworms are plentiful. They’ve invested in Global Positioning System (GPS), yield monitoring, and variable rate soil testing. They soil test every three years – applying lime and nutrients accordingly – and practice control traffic for spraying and for planting.
Because Tim and Tommy have used no-till for so long, they aren’t as hard pressed to follow the contour. By driving straighter rows, using Round-up, and irrigating with center pivots, they’ve been able to increase yield. The only thing missing from their conservation plan was continuous root growth. So in 2014, with technical and financial assistance from NRCS’ EQIP, they planted 560 acres with a 5-way cover crop mixture: 20 pounds cereal rye, 26 pounds wheat, 5 pounds crimson clover, 2 pounds turnips, and 2 pounds tillage radishes per acre. They used 100 pounds of potash as a carrier and broadcast the cover seed on about 320 acres, while the rest of the acreage was aerially seeded. All of the acres were planted between October 1- 15. In 2015, they planned to plant an additional 700 acres in cover.
As time drew closer for termination of the cover in early April 2014, they were concerned about the field drying out due to the cover up taking approximately 1” of water per day, but it never became a problem. After rains they could get on the fields 1 to 2 days earlier without compacting the fields, they said, and noticed soybean plants had grown twice as tall. They planted corn 2-3 days after termination and the beans 1-2 weeks after termination.
The brothers say the cover crops have eased mare’s tail and morning glory pressure and cooled and protected their soils.The soils infiltrate better and the water coming out of culverts near terraces is clear. They also say they have more uniform stands, since the organic matter has increased, and haven’t had problems getting stands due to erosion.
The Colberts attend some regional conferences on cover crops and soil health and regularly attend round-table discussions on soil health hosted by NRCS. These conferences motivated them to want more from their farming operation; to increase yields with fewer inputs, infiltrate more water, and improve their profit margin.