Category Archives: Research
On-Farm Research: Last week a team of us did a series of meetings throughout the State regarding on-farm research updates. It’s always great to have the farmers presenting their research and adding in additional details that we didn’t have when the results booklet was published! Two more meetings continue in western Nebraska this week.
Perhaps my biggest reason for strongly promoting on-farm research is because there often is no better way to obtain answers to some of the questions you all have. These types of studies are often difficult to obtain funding (or can take months to obtain funding, resulting in a lost window of opportunity) and by conducting this research on your farms, we obtain the answers for your specific situations. Sometimes challenges such as storm damage also become opportunities to answer a question via on-farm research. Growers tend to appreciate research conducted on other growers’ farms when we share this research at various meetings, field days, and in articles. A variety of topics are researched every year including nutrient management, various products, row spacing, and new technologies including multi-hybrid planters, use of drone sensors, etc.
In this week’s UNL CropWatch at http://cropwatch.unl.edu, three on-farm research cooperators are featured. One of these is Ken Herz along with sons Zach and Aaron in the Lawrence, NE area as first-time cooperators. Ken approached me with several questions the winter of 2015. As growers with a non-irrigated, no-till wheat/corn/soybean rotation and a cattle operation, his family was curious about the impacts of grazing cover crops for cattle gains and improving soil organic matter. They were also curious about the trade-offs of the cover crop vs. any soil moisture loss or impact on the successive corn yield. They also wanted this study to be something that would be applicable to what farmers in this area did and something they could all learn from together. Thus, it was decided to not plant cover crops into the corn or soybean residue as that isn’t common and this would need to be a long-term study. Dr. Mary Drewnoski and I met with the Herz family to develop a plan for this study. Also thankful for Dr. Suat Irmak for his help in providing additional soil moisture equipment and advice I needed, to the Little Blue NRD in partnering with reduced cost of soil moisture equipment and also for the partnership of Green Cover Seed.
In 2016-2017, this study evaluated four treatments on the effects of successive corn yield: 1-ungrazed wheat stubble 2-grazed wheat stubble 3-ungrazed cover crop 4-grazed cover crop. Wheat was harvested July of 2016 and a five-species cover crop mix of spring triticale, winter peas, oats, collards, and purple top turnips was planted August 14, 2016 (they wanted a mix that would winter-kill). The cover crop received moisture within a week of planting that allowed for germination. Some additional fall moisture allowed for good growth and cover crop biomass was measured (3401 lb/ac) prior to grazing 28 (1100 lb) first-calf heifers for 22 days resulting in the cover crop carrying 2.4 animal unit months (AUM)/ac. The goal was not to graze too heavy to allow for ground cover and any long-term soil improvements, thus 2177 lb/ac of biomass was present post-grazing. Soil moisture was monitored from after cover crop planting through corn harvest. The soil was so dry after wheat harvest prior to planting the cover crop that it took using a drill to install the second and third foot moisture sensors. Beginning soil health parameters were also taken to be compared long-term in this study.
Corn was planted May 15, 2017. Prior to planting the corn, the soil moisture where the grazed and ungrazed cover crop plots were located were at 35% depletion (top three feet) compared to at field capacity (full soil moisture profile) in the grazed and ungrazed wheat stubble plots. Eight inches of rain in May evened out the soil profile allowing all plots to be at a full profile (top four feet) at the beginning of the corn growing season. As the season progressed, the grazing treatments started separating out from the ungrazed treatments from July through end of the season. I don’t know how to explain that yet.
Corn was harvested the Thursday of the major wind event with a calibrated grain wagon. Yields were not statistically different and were 218 bu/ac, 211 bu/ac, and 213 bu/ac for the ungrazed wheat stubble, grazed cover crop, and ungrazed cover crop respectively. The grazed wheat stubble treatment yielded 212 bu/ac but only had two reps at the end of the growing season so was not included in the statistical analysis. Economically, grazing the cover crop was as competitive as the ungrazed wheat stubble treatment when it came to ensuing corn yields and the spring rains made all the difference in beginning soil moisture. Because of the crop rotation, there wasn’t an opportunity to add a cover crop in this field Fall 2017. The Herz’ feel they lost an opportunity as environmental conditions vary so much every year, and this year, cover crops didn’t have as much growth in area fields. Thus, they’ve chosen to dedicate three fields to this study topic in the future, allowing for one of the fields each year to have wheat/cover crop/grazing to account for environmental variation. Continuing this for the next 5-7 years will better answer their questions while benefiting all of us with what is learned. Perhaps other growers are interested in some variation of this study for your farms?
Most studies are not this in depth and this is just one example of how growers are answering questions they have for themselves via on-farm research. It can take extra time at planting, harvest or other times of the season depending on the study. I believe most growers I’ve worked with would say the effort has been worth it to scientifically answer their questions for themselves. Truly am grateful for all of you I’ve had the opportunity to work with via on-farm research! So, if you’re thinking about a question you’d like to answer on your farm this year, consider reaching out to me or your local Extension educator and we’d be happy to talk with you now about how to set up your study. It is important to talk this through, especially if this is your first time conducting research. If you’d like to learn more about on-farm research, view some protocols, or view results from previous studies, please check out our website at http://cropwatch.unl.edu/farmresearch.
Bake and Take Month: March is Bake & Take month, a time when wheat organizations encourage others to bake a wheat good and share it with family, friends, neighbors, co-workers and shut-ins. In honor of the month, the Nebraska Wheat Board (NWB) is again sponsoring recipe cards and stickers for any 4-H groups or other organizations that wish to participate. This year’s recipes are mini dessert tacos and crockpot cherry chocolate lava cake. Those interested in participating or who have questions can contact the NWB office at (402) 471-2358 or email@example.com. There is no cost for the supplies, and no limit on the number that can be requested. Those wishing to preview the recipes before requesting materials can find them listed at http://wheat.nebraska.gov starting March 1.
York County Fair Volunteers: Gary Zoubek asked me to mention he’s looking for a few volunteers that could help with 4-H and Open Class primarily on entry and judging day in Ag Hall on July 31 and August 1st. If you’re interested, please contact Gary at 402-326-8185 or email firstname.lastname@example.org.
March 10th marks the third annual Nebraska Ag Water Management Network Conference with 2016 being the 11th year since the Network was formed! If you’re interested in learning how you can better schedule your irrigation in addition to learning about the latest in irrigation research from Nebraska Extension, consider attending this free event!
Many stalks in Nebraska are left ungrazed for various reasons. One reason I’ve heard is the potential impact of increased compaction and reduced yield of the next crop. Nebraska Extension has long-term research addressing this concern…in fact, 16 years of research conducted at the Ag Research and Development Center near Mead. There’s various components to this study and you can view the full report at: http://go.unl.edu/8mp6.
In this study, cattle were allowed to graze corn residue in the spring (February to mid-April) or the fall (November through January) and these treatments were compared to an area not grazed. Corn and soybeans were planted the spring after grazing the residue for 16 years to determine the effect of grazing on the subsequent crop yield.
In the fall grazing treatments, the corn and soybeans were planted no-till. For corn or soybeans planted into the spring grazing treatments, three tillage treatments were also implemented for nine years: no-till, ridge-till, and spring conventional till, after which all treatments were converted to no-till. This result of the tillage by spring grazing treatments for either corn or soybean yield over nine years showed no interaction and suggested the same effect on yield regardless of tillage treatment used after spring grazing.
Spring grazing across all tillage treatments did increase soybean yields statistically (58.5 bu/ac for spring grazed vs. 57.0 bu/ac for ungrazed) and had no effect on corn yields. The results were similar looking at 16 years of grazing vs. not grazing under no-till for both corn and soybeans in the spring; there was no yield effect found for corn and the soybeans showed a slight yield increase with grazing.
Looking at a 10 year period of no-till management for both spring and fall grazed corn residue and subsequent corn and soybean crops, fall grazing statistically improved soybean yields over both spring grazing and no grazing (65.5 bu/ac vs. 63.5 bu/ac and 62.1 bu/ac respectively). No grazing effects were observed on corn yields in either season. All statistics were at the 95% confidence level meaning the researchers were 95% confident any yield differences were due to the treatments themselves vs. random chance.
Regarding compaction, in the fall, the field was typically frozen and the researchers felt any mud and compaction associated with grazing cattle was minimized; highest subsequent soybean yields were achieved with fall grazing. The spring treatment was designed to look more at potential compaction and muddy conditions after spring thaw till right before planting-thus the implementation of different tillage treatments as well. They used a stocking rate consistent with UNL grazing recommendations resulting in removal of half the husks and leaves produced (8 lbs of leaf and husk per bushel of corn grain produced). Results of this study indicate that even with muddy conditions in the spring, grazing increased subsequent soybean yields compared to not grazing regardless of tillage system used and that corn yields were not different between grazing vs. not grazing and regardless of tillage system used in the spring. This study was conducted in Eastern Nebraska in a rainfed environment with yields ranging from 186-253 bu/ac with a 16 year median yield of 203 bu/ac.
Additional Grazing Study
A five year fall grazing study (December through January) was conducted in an irrigated continuous no-till corn field at Brule, NE to determine the effect of corn residue removal via baling corn residue or fall grazing on subsequent corn yields. That environment receives limited rainfall and residue is deemed important for reducing evaporation of soil moisture in addition for catching/keeping snow on fields. Farmers were questioning the effects of any residue removal on subsequent corn yields and the study was implemented.
Treatments were 1) fall grazing at 1 animal unit month/acre (AUM), 2) fall grazing 2 AUM/ac, 3) baled, or 4) ungrazed. The researchers found that residue removal did not affect corn grain yields from 2009-2013 in the continuous corn rotation. There were no statistical yield differences with 5 year average yields of: 152 bu/ac, 155 bu/ac, 147 bu/ac and 148 bu/ac respectively for the above-mentioned treatments.
Grazing corn residue provides many benefits to both livestock and grain farmers, yet many corn stalks in our area are not grazed for various reasons. With as much hail as we’ve had this fall, grazing is also an option to remove ears and kernels that were lost, preventing volunteer corn next season. Normally there is less than a bushel of ear drop per acre, but we most likely have more than that in some of our fields this year. Two kernels per square foot or one ¾ pound ear in 1/100 of an acre is the equivalent of 1 bu/ac yield loss. In 30” rows, 1/100 of an acre is 174’ long if you count in one row or 87’ if you count in two rows.
What may also be of interest to you is a recent finding between corn grain loss pre-and during harvest and sudden death syndrome (SDS) of soybean. Many asked me this this year, “Why did I see SDS this year when we’ve never had it in this field before?” It’s a great question and I often responded by saying we need to sample the areas affected with SDS for soybean cyst nematode (SCN) as the two diseases are synergistic. Sampling for SCN still remains free through your Nebraska Soybean Board Checkoff dollars and you can stop by the Extension Office for free sampling bags. Crop consultants should contact the UNL Plant and Pest Diagnostic lab directly at (402) 472-2559 if you are requesting 10 or more sampling bags.
Anything that moves soil can transport the fungal soil-borne pathogens causing these diseases. But recent research from Iowa State University also suggests that the fungal pathogen causing SDS (Fusarium virguliforme) survives on grain lost during the harvest process in fields and that SDS management in soybean actually needs to begin at corn harvest.
Studies were conducted for two years in greenhouse and in field plots with nine treatments to determine the survivability of Fusarium virguliforme (Fv) on corn and soybean residue. The treatments were: 1-Corn kernels + Fv; 2-Corn roots + Fv; 3-Corn stem/leaves/husk + Fv; 4-No residue + Fv; 5-Soybean seeds + Fv; 6-Soybean stem/leaves/pods + Fv; 7-Soybean roots +Fv; 8-Corn stalk on soil surface + Fv; 9-Corn kernels and stalk on soil surface + Fv. The researchers consistently found in both the greenhouse and field experiments that Treatment 1 of corn kernels at average harvest loss resulted in the most SDS. Treatment 2 consistently resulted in the second most SDS.
This helps to explain why some farmers are finding SDS in fields that have been continuous corn for a period of years, are finding SDS in corn and soybean rotation when little or no SDS was previously observed, and why SDS has increased in seed corn fields that may have higher harvest losses. They did not experiment with tillage systems and their recommendation is to reduce harvest losses to reduce the risk of SDS.
Grazing residues can reduce your risk from these harvest losses and for those losses which were incurred with the hail/wind storms we’ve experienced since Labor Day. When grazing corn residue, cattle are selective. They will eat the grain first followed by the husk and leaf followed by the cob and stalk.
It’s also important to be aware of grazing restrictions from herbicides applied to row crops; you can read more about that in this post.
Corn is approaching or at V7-V8 growth stage. A few weeks ago, we published research results in our UNL CropWatch website. That information can be found in the links below the video. If you are interested in trying this in your field this year, please see the Nebraska On-Farm Research protocals also shown below.