This is the sixth in a series of “Profiles of Soil Health Heroes.” This profile features Tim and Tommy Colbert, Chester County, Tennessee. The brothers began farming in 1973. The farming operation is located near the Jack’s Creek and Plainview Communities of Chester County. Their soils are of the Lexington-Providence soil series made up of loess cap over Coastal Plain parent material. Soils are predominantly silt loams with some bottom lands somewhat sandier in texture.

What stands out about the Colbert brothers the minute you get out of the truck, is their can-do attitude. They shared with me and Brad Denton, NRCS District Conservationist, Madison and Chester Counties, the history of their farming and conservation practices. They constructed terraces in the 1970s and 1980s. The entire farm at their headquarters is terraced. It was laid out on the contour. They told me after the terraces were constructed that they reduced the gully and rill erosion and followed the contour for many years.

Like most West Tennessee row-crop farmers, their main enterprise was cotton, and for years they had it as the mainstay of their enterprise. They became one of the earlier adopters of no-till in Chester County. Once they adopted no-till, they stayed the course. They did not practice rotational tillage and use of different implements such as harrows or vertical tillage. Their oldest no-till field is thirty plus years, where all of the other fields have been no-tilled 20 plus years.

Their soil organic matter at 0-6” depth was approximately 1%, ten years ago. They transitioned to a diverse conservation crop rotation approximately seven years ago. They farmed cotton, corn, full season soybeans, and wheat, double cropped soybeans.

Their cropping enterprise consists of approximately 1,700 acres, 450 acres of wheat, double cropped soybeans, 400 acres corn, 825 acres of full season soybeans, and 25 acres Cereal Rye for seed. This year, 2015 is the first time in 29 years that they have not grown cotton.

Since adding diversity and higher residues to their rotations, in addition to their long-term no-till, they have experienced increases of soil organic matter (SOM) on all of their fields. I viewed some of their soil tests and jotted down the % SOM. They were 2.2, 2.7, 3.0, and 4.0%, respectively. They figure their farm average is 2.5 – 3.0 %. You can also see a progression of conservation, from terracing on the contour, to no-till, and to conservation crop rotations.

Table 1. Example of three fields tested 2012. Nitrogen is applied at 200 lbs. acre for dryland corn and 240 for irrigated.

Field number	pH	Organic Matter	P2O5 Analysis, and pounds per acre	K2O Analysis, and pounds per acre
1	6.5	3.0 %	Medium, 70	Medium, 98
2	6.3	2.7%	Medium, 70	Medium, 79
3	5.8	3.4%	Low, 112	Medium, 108

Field 3 recommended 1500 pounds lime per acre.

They have also invested in Global Positioning System (GPS), yield monitoring, and variable rate soil testing. They soil test every three years, and apply lime and nutrients by variable rates as shown in Table 1. They practice control traffic for spraying and for planting. With no-till and their desire to add cover crops on all acres, they no longer need to follow the contour of the terraces. Since they added this technology, they drive straighter rows, thus increasing yield.

They use Round-up technology. They irrigate on a few fields with center pivot. The Colberts mentioned, that due to size and shape of their fields, they only have approximately three center pivots. Tim and Tommy also mentioned that their desire was to increase organic matter in order not to depend on irrigation as much.

In many farming operations, I could end here, and say they are doing an outstanding job. This is where their can-do attitude kicks in. They attended some regional conferences on cover crops and soil health. They attend a regularly scheduled round-table of discussion on soil health at Brad Denton’s office. These conferences motivated them to want more from their farming operation. They desired to increase yields with no more inputs, infiltrate more water on the farm, thus improving their profit margin.

In 2014, they made their next step up in their well-rounded conservation program, they added annual cover crops. They had already been following some principles for improving soil health: 1. Keeping the soil covered with 20+ years of no-till and use of crop residues and crop rotations; 2. Reduced disturbances by no-till and reducing pesticides by the use of crop rotations and less monocultures; 3. They had increased diversity, especially with their added crop rotations from their earlier cotton-dominated rotations. 4. The only thing they lacked was continuous root growth. With technical assistance from NRCS and financial assistance from NRCS, Environmental Quality Incentive Program (EQIP), they embarked with 560 acres of cover crops planted in the fall of 2014.

They are very pleased so far with the results of the 560 acres of cover crops. I asked them if they had problems planting. They used a combination of planting methods. They planted the crop fields that came off earlier with a fertilizer truck using 100 pounds of potash as a carrier and broadcast the seed, about 320 acres. They planted the rest of the 240 acres aerially using an airplane. All cover crops were planted by October 1-15.

I asked them to expound on their experiences good or bad and any concerns or changes they would make. As time drew closer for termination of the cover in early April, they were concerned about the field drying out due to the cover up taking approximately 1” of water per day. This did not become a problem. They noted, after rains they could get on the fields 1-2 days earlier without compacting the fields. Where they allowed the test plot to grow three extra weeks longer, they noticed soybean plants twice as tall as the earlier terminated cover. The less cover had 87,000 plants per acre (soybean) compared to 110,000 soybean plants per acre for higher growing cover, killed three weeks later. The planters had no hair pinning problems. They planted corn 2-3 days after termination and the beans 1-2 weeks after termination.

Their general weed control is Round-up Power Max with combinations of Valor and Verdict. They use treated seed. Corn is scouted but no additional fungicides are used. Soybeans have always been sprayed with fungicides in the past. They want to continue to scout and see if covers and rotations can reduce fungicide use in soybeans.

The soils infiltrate better after long-term no-till. The Colberts remarked that the water is clear coming out of culverts near terraces. They also noted that they can enter their fields 2-3 says earlier than farmers that use tillage. They also noted that there are more uniform stands since the organic matter has increased. They do not have problems getting stands due to erosion. The stands are very uniform.

Also since increasing organic matter, they now drive their equipment straight, not following contoured terraces. With variable rate fertilizing, yield monitors, and GPS, they can drive straighter and see some yield advantage.

In summary, Tim and Tommy Colbert wanted to increase SOM and improve their yields for 2015. They were already excellent conservation farmers. They had been in a more diverse rotation for seven years, using variable rate technology, yield monitors and GPS steering system. They wanted to maximize the use of rainfall in West Tennessee, through improving infiltration. They embarked on an aggressive first year of planting 5-way cover crop, 560 acres and plan to add approximately 700 more acres in 2015. They have learned a lot in less than a year on planting and managing diverse covers. They plan to lengthen the time of growth to 2-3 weeks before termination. They plan to narrow corn width rows and experiment with closing wheels. I know one thing, “whatever it takes; they will make it happen.”