No-till Tobacco with Cover Crops improve Soil Health and Increase Farmer's Profits
Tobacco is not normally thought of as a crop that improves soil health. By the time George Washington returned to Mount Vernon in the 1780s, tobacco was a predominant cash crop in the colonies and had been since 1611. Like his father before him, Washington grew tobacco. He noticed the land had lost its fertility. George Washinton replaced tobacco with wheat and began a crop rotation system to bring life back into the soil. Many years after, we are still trying crop rotations that will improve our soil health. Traditionally, tobacco is plowed and followed by at least two other secondary tillage methods to smooth the field prior to transplanting. Even though tobacco is normally rotated, a typical tobacco field can suffer from soil erosion during the years in tobacco. When you examine a traditionally plowed tobacco field, one normally does not see many soil health indicators improving.
That what makes this Profile of Soil Health Hero unique. Corby Brown grows no-till tobacco and is improving soil health. Corby is our 24th Profile of Soil Health Hero. He farms in Macon and Clay Counties, Tennessee, as well in Monroe, Barren, and Metcalf Counties, Kentucky. Corby grows personally approximately 250 acres of Burly tobacco. He works with his son, Christopher, and nephew, Elliot. Their combined acres total approximately 1,000 acres of Burly tobacco. There are also others in his family involved. Corby is the specialist for setting tobacco where Christopher focuses on fertility, and Elliot on weed management. They all have their personal farms but work together as far as advising and assisting one another. Corby also grows corn, soybeans, and some cereal rye. He also grows some sweet potatoes. His tobacco is planted in 40" rows. Corn and soybeans are planted on 20" rows. He annually soil tests. He maintains a pH of approximately 6.2 or greater. His yields in the last three years have been approximately 70 bushels of soybeans, 210 bushels of corn per acre, and 1600 - 2100 pounds of tobacco per acre.
I visited the farm on September 22, 2016 with Eric Copas, District Conservationist, and Kerry Craig, Soil Conservationist, both with NRCS for Macon and Trousdale Counties, Tennessee. Generally, Mr. brown's rotation is 3 years of Burly tobacco, one year of corn, and one year of soybeans. They have brought corn and soybeans in the rotation since 2011. With their annual soil testing and applying nutrients by soil test results, Corby also applies chicken litter periodically. He said they applied more in 2015, and much less in 2016.
I asked Mr. Brown about his tillage practices since he has been farming. He has always believed in no-tilling when possible. He has always practiced strip tillage or no-tillage with his grain crops. I asked him what led him to transition to no-till tobacco. He said they started strip tilling tobacco over 10 years ago. He used a 4-shank strip-till with ripper and off set disk coulter. He noted that the disturbance in the rows were approximately 14". With the soil disturbed, and erosion and soil health not improving, he wanted to transition to no-till. He said the biggest reason was that most fields tilled washes and ends up in the road. He did not like to see bare ground. He saw too many gullies. He said he did not feel pressured due to environmental laws or rules. He wanted to no-till because it was the right thing to do and it made sense on a business sense and environmental sense. He said technology and chemicals improving have made it possible to no-till his tobacco.
Corby began working with Checci and Magli, an Italian company on designing a 4-row no-till tobacco setter. The company sent to planters over, and his endeavor began in no-till tobacco four years ago. Corby has been working with the company on needed adjustments. After numerous modifications, he has an excellent transplanter. The current planter is working well. It has row cleaners, a fluted coulter, and ripper. He had been using a cover crop in his tobacco for over 15 years. He is presently planting 2 bushels of wheat per acre on his crop land. Some acres receive cereal rye as cover. He has been using the heavier rate since 2011. Up to this year he has broadcast his cover crops and used a light disking to cover the seed. He said they normally disk down to 2". This year, 2016, he is drilling 100% of his acres with no tillage. In their soils on bottom lands, they disk some to repair ruts. They are hoping to be able to no-till drill the bottoms too. Typically, they begin terminating cover in early in April through late April. He plants 14 days after terminating cover. He staggers his tobacco planting from May 1 through June 15 to make it easier for harvest crews. They want to pursue aerial seeding in corn and soybean fields to plant covers earlier. They plan to begin planting earlier on earlier tobacco harvested fields. They expected all tobacco fields to be drilled in the next few days.
During our day together, we dug holes in some of his fields. The first one was a one-year no-till tobacco field. The field had fairly thick platy structure from past years' tillage including disking for cover crops. Roots were penetrating plates. I also dug up some grass in a fence row to show our goal which is to have crumbly and sub-angular blocky structure. This takes time with no disturbances from tillage and continuous root growth. We saw some positive signs in a field that had been in no-till tobacco for two years. We expect this year of drilling cover crops and now some years of two to three years of no-till will show soil health improvements. The field that had been in two years of no-till had a much stronger earthy aroma. The year of first year no-till had an odorless smell. We saw much more biology signs in the two years of no-till compared to one year no-till. We saw similar findings in two soybean fields. The second soybean field had less disturbances and was much further along in soil health improvements compared to the first soybean filed that had more disking previously for cover crops. Corby and his partners were taking all of this in like sponges. They asked questions on how to further the improvements they were seeing.
We discussed continuing to reduce disturbances from tillage. They have committed to do continuous no-till. They are already using some rye on some fields. we talked about expanding cereal rye for better pig weed control. we discussed bringing in some legumes as well as brassicas such as tillage radishes and purple top turnips. They are considering some diversifying cover crops. As we look over their farm and dug many holes, we observed and discussed some of their benefits from no-till tobacco and use of cover crops. Compared to nearby tobacco fields that were tilled, erosion was not present. They have noticed some better yields, especially with tobacco being drowned out in some fields last two years and extreme drought this September that browned up many leaves. Their fields held more moisture. The cover which is still present at harvest reduced soil temperatures and reduced evapotranspiration. They noticed better infiltration during intense rainfall events. Eric Copas said that there are about 400 acres of no-till tobacco in Macon County. He notices less drowning out of tobacco.
The Browns are making significant changes in their tobacco operation. I noticed several earth worms in tobacco fields. That is normally not the case in tobacco fields. Just like George Washington found over 200 years ago, that rotations to wheat and use of manure and other soil amendments would bring his fields back to life, Corby Brown is using no-till tobacco, corn, and soybeans with chicken litter, and cover crops to improve his soils and to improve his profits. Better soils mean better crops.