Updates on Soil Health Hero Number 1, Danny Powell, and Soil Health Hero Number 3, Matt Griggs
The Profiles of Soil Health Heroes are now up to 32. Danny Powell was our first hero and Matt Griggs was the third in Profiles of Soil Health Heroes. Their progression in use of cover crops and managing cover crops have warranted an update on each of them. I had the opportunity to visit Matt Griggs on February 7, 2017 and Danny Powell on May 15, 2017. Below are the updates from each of their operations.
Danny Powell Update
Danny Powell was our first in the series of Profiles of Soil Health Heroes. I completed the write up in November of 2014 and published it in the spring of 2015. A lot has transpired since that first article was written. Danny is in his sixth year of cover crops on one field. He has purchased other fields and now is beginning to plant crops in first year cover crops on new fields that he obtained. Danny farms 2,900 acres. He owns approximately 1,300 acres. All of his owned acres are in cover crops. His crop rotation is corn-winter cover crop mix-soybeans and winter cover crop mix. He recently purchased a 30 feet John Deere 1990 Air-seeded drill. He plants or drills 100% of his cover crops with the drill.
Danny has received financial assistance from NRCS and Tennessee Department of Agriculture to apply soil health management practices. It is significant that he is also planting cover crops on several acres without financial assistance. Danny sees the benefits to his bottom line to continue the practice of no-till and diverse mixture of cover crops. He said that overall the yields were more consistent, crops were stressed less, and variability was less even though there are still areas that are higher in fertility and productivity. He credits it anecdotally to increased soil organic matter and the more efficient use of water and nutrients.
He is now set up to plant corn on variable rate varying by soil productivity from 34,000 - 36,000 plants per acre on dry land corn in the field that has been in covers for six years. His corn variety is a 108-day corn. He produced 250 bushels last year (2016, a drought year). He plants in 30" rows. Soybeans are planted in 15" rows. He soil tests in 2.5 acres grids. Danny applies fertilizer and lime by variable rates. He has noticed less lime being required after six years of using cover crops. Phosphorus (P) is staying mostly high, but potassium (K) is called for annually by soil test results. He is applying 2 tons of chicken litter per acre on most fields annually and continues to monitor P. We looked at four fields on May 15, 2017, Danny Powell, Pam Hoskins, NRCS District Conservationist, Woodbury, Tennessee, and myself, Mike Hubbs, TACD Soil Health Specialist and author of the series on Profiles of Soil Health Heroes. We looked at "the original" field, Church field, McMahan Field, and Ponderosa field. The original field has been in cover crops the longest, so I will designated it as the original field. Danny is farming some soils with limited depth and naturally low in fertility, Dickson Silt Loam and Sango Silt Loam, 2-5% slopes. This makes what he is doing more impressive with the limitation of some of these soils.
All four previously mentioned fields are planted to the same cover crop mixture, usually planted in early September after corn and late September to early October after soybeans. The mix is a five-way mix consisting of cereal rye, bob oats, Austrian winter Peas, crimson clover, and Daikon radishes. One change in his mixture over the last six years is a slight increase in grass because of the need to increase carbon because of increased soil biology. The soil biology is now decomposing crop residue within a year. Soils are more aggregated and nutrients are cycled more readily.
The "original field" has been in six years of covers. The Church field has been in covers five years. The other two, McMahan and Ponderosa are in their first year of covers. Besides the variable rate seeding at planting cash crops, other recent change is leaving covers growing longer. When he began using covers, Danny terminated the covers at approximately knee-high (24"). He slowly progressed to waist high (48"). Now, he is letting covers grow to head high (60" plus). He says the higher cover crops have their challenges. He is willing to tackle the challenges in order to receive more benefits from the cover. Another discovery, he has made due to experiences, is planting green (planting cash crop in live cover crops) allows him to maximize height and kill after planting at boot stage in grass and early bloom for legumes. He ideally likes to plant green in standing cover and follows planting with cultipacker to roll or lay down cover crops and then apply a herbicide such as GramoxoneTM plus 15 gallons of liquid nitrogen (N). Based on scouting in corn, he applies, as needed, AtrazineTM and Armazone ProTM. When planting in standing green cover crops, sometimes the the Austrian winter peas will wrap around planter. To alleviate the wrapping, he has fabricated 42' pipe, that can be filled with water to add weight, and he drags it to lay down cover and then plants in cover and then applies herbicide on laid down cover. Danny says that laying down the cover makes managing the heavier cover easier to handle. He urges farmers who are considering leaving cover crops to 60" or higher to plant at a slower speed. He stresses the need to plant corn at 2" depth. He drives about 4.2 miles per hour when planting in heavy covers. He uses a front leading coulter, double disk openers, seed firmer, and cast iron closing wheels. He has removed his row cleaners this year. They were being wrapped with the peas. Both methods described above of planting are giving Danny good stands of corn and soybeans in 60" of height of cover crops.
Danny said that he has not significantly reduced inputs over the entire farm. He does not use fungicides on a regular basis for corn. He scouts and uses fungicides as needed in soybeans, so there are savings most years. He expects less disease pressures with use of diverse plants in cover crop mix. Also there is no soil splash on plants. However, he is in the third year working with Coffee County Soil Conservation District to try some cutting back on N in some plots following the Haney test. He set up some plots to follow the Haney test recommendations. In year 1 with soybeans, the Haney test recommended zero inputs. He followed the recommendation with no yield loss compared to the rest of his soybeans. In year 2, the Haney soil test recommended 75 units of N for corn. He normally applies 210 units of N. He followed the 75 units of N in the test plot and yielded only 14 bushels per acre less than his regular corn fields. Even though the Coffee County study will end this year, Danny wants to continue the testing on his own using the Haney test and expanding the test plot area to double the size of the current plot, and continue working with reducing inputs. He is seeing less weed pressures and also less lime being called for by soil test. Danny sees in his yields the better use of water infiltration, water holding capacity, and more fertility from decomposing carbon inputs from cover crops.
Danny credits the six years of covers to taking stress off crops during short-term droughts. His yields were very good in 2016 in spite of the drought, 250 bushels per acre for corn and 70 bushels per acre for soybeans. He stressed that farmers should start in small acres when trying cover crops. He also stated that farmers should kill covers at knee high when beginning covers. He said that he saw differences in water infiltration the first year using covers. The soil biology changes are more evident approximately three to four years after applying cover crops.
As we dug in Danny's fields, it was evident that soil carbon was increasing. The soil had a darker surface, and the shovel easily penetrated the top 6" with little resistance. As I pulled back the covers in the field that had been in covers for six years, I noticed the crop residues from last season were being decomposed readily by the soil biology. There were evidences of earthworm casts. We found five to six earthworms in approximately 1/3 of shovel full. The soil biology is increasing after six years of cover crops. Soil structure was granular at surface and sub-angular blocky below the surface. Soil smell had a strong sweet earthy smell. I have seen enough fields without covers and fields with covers to see that this field was really improving in its soil health.
Danny's progression shows that he had seen the need to increase the biomass by delaying on killing covers and planting green. This will allow more biomass of covers when planting cash crops and as a result received more benefits from cover crops. Many times farmers do a great job obtaining good stands in the fall of cover crops only to kill them too early in the spring missing or delaying some of the benefits. He also has progressed by purchasing equipment to plant by variable rate and apply nutrients and lime by variable rates which results in better yields and profits. He also has begun to roll cover crops instead of planting in standing cover since he has gone from waist high covers to head high covers. Danny was doinfg a great job in improving his soil health when I did the intial article on him. He has progressed in the last two years with consistency in using cover crops resulting in more improved soil health and soil productivity.
Matt Griggs Update
When I visited Matt in February of 2017, I was with Brad Denton, NRCS District Conservationist, Jackson, Tennessee, and Dustin Graham, District Conservationist, Bolivar, Tennessee. Matt Griggs is now in his fourth year of cover crops. Matt has switched agronomists for soil testing. The original agronomist switched methodologies, sampling different depths from 6 inches to 4 inches without Matt's permission. The different depths made it seem like fertility as well as soil organic matter were increasing more than what was reality. With these changes in soil sampling, it is impossible to show credible progress from soil tests from his change in management the last four years. Matt continues to apply chicken litter at 1.5 tons per acre which he has done for five years. With all of the changes in soil testing, he recently sampled his soil organic matter. His average is approximately 2.5%. His beginning levels were approximately 1.2-1.5%. With his sampling methods stable on 2.5 acres grids, he now has a good baseline to detect changes in the future.
Currently, Matt's cover crop mix before cotton and soybeans is 30 lbs. cereal rye, 2 lbs. annual rye grass, 8 lbs. of crimson clover, 8 lbs. Austrian winter peas, 4 lbs. hairy vetch, 4 lbs. of daikon radishes, and 4 lbs. of buckwheat per acre. His cover crop mix before corn is slightly adjusted to lower carbon to nitrogen ratio. The mix is 10 lbs. of cereal rye, 10 lbs. oats, 2 lbs. of annual rye grass, 4 lbs. of buckwheat, 10 lbs. of crimson clover, 10 lbs. of Austrian winter peas, and 6 lbs. of hairy vetch. Note, grass is reduced and the legumes in the mix are increased up to 2 lbs. per acre from the previously mentioned mix prior to soybeans and cotton. Matt has been consistent with this mix and likes what he is seeing in his fields.
Matt's crop rotation currently consists of corn-cover crop mix-soybeans-cover crop mix, and cotton-wheat-double cropped soybeans. One major change, since I wrote the Profiles of Heroes (see Matt Griggs, Soil Health Hero number 3) is he now uses a crimper/roller prior to planting his cash crops where applicable. Matt rolls his covers because he is trying to maximize height of covers at time of killing them to maximize benefits of cover crops. Matt also sees benefits from weed suppression to leave longer which is why he is now planting green. In other changes in his operation, he now plants his cash crops into green cover crops instead of planting later after killing cover crops. He plants corn at approximately knee-high to thigh-high cover crops (usually mid-April). One needs either boot stage in grass and early bloom in legumes for cover to stay on ground when rolling, see roller/crimper fact sheet at tnacd.org, under newsroom. He terminates cover crops up to waist high for full-season soybeans (April 20-25). He plants cotton in 6-7' cover crops (May 5-10).
Matt then applies his burn down herbicides. His recipe of herbicides at burn down after planting green is for corn, 1 quart of ParaquatTM when a follow-up of 1 quart of Round-upTM 2 weeks after planting. Corn is planted in green cover at about knee-high height. Initial burn down herbicide is applied same day to a couple of days later. At V-5 growth stage, an additional application of Sequence (glyphosate plus DualTM) at 40 ounces per acre.
For soybeans, he uses the same burn down with soybeans. Matt says he then scouts and 50% of the time he applies 40 ounces of SequenceTM and 50% no additional residual herbicides. For cotton he uses same burn down. He follows up with 40 ounces of Sequence at 2 weeks after planting then additional 40 ounces of SequenceTM at 4 weeks after planting. Matt grows group 4.7 soybeans for his full-season beans and group 4.9-5.1 for double cropped beans after wheat.
Another step of progress since Matt attended the Dave Brandt farm (see A Day with Dave in newsroom, tnacd.org), he worked with NRCS to set up some test plots on six acres. The treatments are no-till without cover crops, no-till with winter cover crops, and no-till, summer cover crops planted in 2015 and again in 2018, and annual winter cover crops.
Matt said that he has made and added custom row cleaners to his planter to get better stands of cotton. This innovation has helped Matt obtain excellent stands of cotton in heavy residues. He has adjusted his nitrogen (N) application at planting in corn because of higher carbon to nitrogen ratio was tying up some of the N during the first three years. There also have been infiltration tests on the plots. The long-term no-till without covers are showing 1-2 inches of water per hour. The cover crop plots are showing approximately 12" per hour on second inch of water. First inch has shown as high as 62 inches per hour. We have noticed that infiltration will change the first or second year as soil structure changes from platy to granular and sub-angular blocky structure. We noticed that soil surface was showing previous crop residue was rotting much quicker due to increase soil biology. Earthworms are especially more numerous since he began using cover crops. Earthworms are a general soil biology indicator that leads speculation that other biology such as more diverse species are also present. We normally see this the third and fourth year after using cover crops. Matt says his stands are getting better each year when planting winter cover crops. The soil is softer and more mellow and stands of covers and crops are much easier to get good stands. There is better weed suppression. Matt says he is using half the amount of residual herbicides on cotton, $25.00 per acre savings. He is also saving on less fungicide applications, $12.00-14.00 per acre. He knows that future soil tests will show progress eventually as he now stabilizing his soil test sampling methods.
Recently (May, 2017), University of Tennessee at Martin sampled his cover crops biomass. They sampled six plots with treatments of winter cover crops and found the following: (1) 31,033 average lbs. of wet biomass from cover crops, (2) 6,243 lbs. of dry biomass, (3) 3.1 tons of average dry biomass; (4) 2% of average N in dry biomass; (5) 127 lbs./acre of N in dry biomass; and (6) 43.4 lbs. of estimated plant available N per acre. Experience and research show that as there are more biomass produced and less losses from tillage and erosion then soil carbon or soil organic matter will increase. Many soil functions improved as soil organic matter increases. Matt sees this in anecdotal evidences.
Farmers that are no-tilling into covers need to see these results. Matt is now rolling and crimping his covers on the surface with a roller/crimper where he can. This provides more soil cover. Soil biology can more readily breakdown carbon to release nutrients and to continue to aggregate the soil. The covers being laid down also aids in weed suppression (blocks sun light to weed seeds and allelopathy). It also aids in planting in heavy residues. Matt is recognizing in early transition to make sure enough N is applied as carbon is increased, especially after summer cover crops with high amounts of grass. He has adjusted his coulters and row cleaners for cotton to make sure he has a good stand in heavy residues. The UT results above shows N is being produced from covers which eventually will lead to savings in N as the system adjusts to increased biology. Carbon is increasing because all of the short-term indicators such as increased earthworms, soil structure improvements, and much better water infiltration. With all of the verified additional carbon being added, there is no way for soil organic matter to go but up. As Matt's has now stabilized his methods of soil testing, we will be able to monitor soil change in time through soil test results. However, visiting his farm now, one can see major changes in the last four years.