From Farming Dust to Improving Soil Health
Neil Delk is a Soil Conservation District Supervisor for the Maury County Soil Conservation District. Neil is 20th in our series of State Profiles of Soil Health. He is from Maury County and farms in Kettle Mills area near Williamsport, Tennessee. Neil grew up farming, but took a break from farming during the time he was drafted into the United States Air force in 1969. He worked some time with the Department of Revenue part-time, and then returned to farming. He supplemented his farming by select timber cutting for 20 years. He retired from timber cutting approximately 8 years ago. In his farm operation he formerly raised cattle and hogs. He grew corn for hogs. Neil transitioned over the years to full-time grain crops.
He shared with Natural Resources Conservation Service (NRCS), District Conservationist, Jeff Bowie and myself that they previously "scarred the land." He went on to say, that "we worked the ground like we thought we had to do. We worked it like dust." Neil also said that "we have not tilled in 20 years. It hurts me to till."
Mr. Delk applies his initial nitrogen in the fall because of height of covers in spring. He grid samples every year. The Maury County Farmers" Cooperative handles his soil testing. He strives to maintain a minimum pH 6.2. Neil said that farmers must learn to no-till, quit disturbing the soil with tillage. He said that when he first grew wheat that he would bale the straw. The results of removing the residue was that the ground was hard. He now grows cover crops and leaves covers on soil surface. No straw is removed, and all grain residues are returned to surface of soil.
Neil credits the chemistry of Round UpTM for the reason he started to no-till. He has attended several soil health conferences. He and other conservationists also visited the farm of well-known soil health farmer and advocate, Dave, Brandt in Ohio. This visit inspired him to really focus on increasing soil organic matter and to improve soil health. Jeff Bowie and Nathan Hicklin, NRCS worked with him to add cover crops to his farming operation. This was approximately six years ago.
Neil farms 500 acres of corn-soybean rotation. Neil would like an alternative to soybeans. He began using wheat as a cover crop. Neil then tried wheat and or cereal rye with crimson clover. He did not understand the nuances of carbon to nitrogen ratio when he started such as wheat cover prior to corn crop. Now, he is fine tuning his carbon to nitrogen ratio using multi species cover crops. He is currently planting four species of cover crops, consisting of 2 pounds of tillage radishes, 15-20 pounds of Austrian Winter Peas, 5 pounds of Crimson Clover, and 30 pounds of Cereal Rye. He is considering purple turnips or rape as a fifth species in 2016. According to recent findings, farmers in Tennessee recently had some difficulties controlling canola and rape this past spring. Some canola and rape did not die when covers were desiccated. We are currently recommending farmers not to use canola or rape until we can gather more research and experiences. He plants cover crops on most of his 500 acres. He runs a one-man operation, and some seasons, he misses a few acres.
Neil aerial seeds or drills all of his multi species cover crops. He plants at harvest. Neil said "that cover crops are not a magic pill; it takes time for soil to change." He has learned if he plants cover crops later, henbit and chick weeds are compete with covers. He has learned that covers are harder on planting bearings, and can wrap around the planter. He no longer uses row cleaners.
I asked him about compaction issues. He has learned that roots are the solution to hard soil. He said steel does not build soil; covers do. He is a believer of the four principles of improving soil health: 1. reducing disturbances (no-till and reduced pesticides, as needed), 2. keeping the soil covered (crop residue management and multi species cover crops); keeping roots growing continuously (crop rotations and multi species cover crops); and increasing diversity (added multi species cover crops).
Neil has learned that cover crops can remove some of his former hindrances from his farming operation. He plants radishes in wet spots. Other benefits that he has noticed are: major reductions in sheet, rill, and gully erosion, more earthworms, soil is more mellow, infiltration rates are higher, soil organic matter in increasing, available water is more apparent with less stress from droughts, soil biology has increased and is thriving, and weed suppression. He said the river ground that he farms would be like concrete if he worked it up. The field now is crumbly and looser.
Weed suppression is very obvious. Neil said the cereal rye is providing allelopathy and is also choking out many young weed seedlings. He also planning to experiment with grazing cover crops by partnering with a neighbor. The neighbor provides cattle, and Neil provides grazing. The grazing brings in manure and also controlled grazing stimulates fall growth of covers. The cattle is provided with high digestible forages.
I asked Neil how his long-term no-till and use of covers for six-seven years have reduced his inputs. He says he saves $30.00 per acre on broad leaf weed control. He uses one application of VerdictTM and CanopyTM for soybeans, and Lead offTM, DicambaTM, a low rate of AtrazineTM, and Round UpTM for corn. He has been experimenting with using GramoxoneTM instead of Round UpTM for corn to get a quicker jump for the corn by killing covers a little faster in spring. He still uses Round UpTM to terminate covers for soybeans. He has quit using fungicides in corn, amounting to $20.00 per acre savings. He uses lower rates of fungicides for soybeans. As the soil biology matures in his fields, he is considering discontinued use of fungicides in soybeans too. He has changed soybean varieties to reduce frog eye.
In his 240-250 acres of corn, he is using Haney soil tests. He is reducing a total of 70 pounds per acre of nitrogen, 30 at planting and 40 at side dress. This is an addition of $20 - $30.00 per acre savings. He uses Urea and 32% liquid nitrogen. He maintains his P and K according to soil test results. Neil has learned a lot about the ecology of cover crops. He still calls himself a novice. He also said that "the more that I learn that I realize how little I know." It is that humility that keeps him improving his operation and his soil health.
His soil is medium quality from limestone. Slopes are flat to gently rolling. He averages around 175 bushels per acre on corn, and 50-55 bushels of soybeans per acre. He has some test plots of no-till corn without cover. We dug into those soils and found basically no structure, massive. Some no-till without cover had platy structure. That is stratified plates. He also had some 100 % crimson clover plots. The plots had been in multi species the year before. Examining the structure we found platy structure. All areas with multi species cover crops, he had excellent crumbly structure at surface with sub angular structure at about 1" depth. It is amazing that one year away from grass in cover crops reduces the aggregation as soil biology breaks down active carbon to release nitrogen. We must grow grass in our covers to produce large amounts of carbon. It is not something you can achieve and then quit. Producing carbon is essential to improving soil health. Growing covers and especially grass is needed to increase carbon and increase aggregation which improves infiltration. You will note by the picture, Neil gets all of the growth that he can with his covers. Farmers need to be patient and get their benefits from covers prior to desiccating them.
He said farmers' attitudes must change to adjust to this type of farming. They must get away from following tradition. "If daddy tilled I must till." Neil said people are comfortable with tillage. He said we must not be hard-headed and continue tilling because that is what others have always done. He said other resistance to cover crops is the perception that it is expensive on the front end. Neil spends approximately $40.00 per acre for multi species cover crops.
Neil continues to say farmers need to adopt this type of farming. Start at the bottom that is learn by using one cover crop, and no-till, and be patient. He said if you till; you must continue to till to take care of problems caused by tillage. Neil has gone from tilling to dust to building high performing aggregated soils that have abundance of soil biology. Other farmers can do the same by reducing disturbances, keeping the soil covered, keeping roots growing, and adding diversity. Better soils produce better crops.