Ag Conference: Thank you to everyone with the York Chamber, Holthus Convention Center, Chamber Ag Committee and Ambassadors, York Visitors Bureau, Sponsors, Vendors, Newspaper and Radio for all their work and help with the York Ag Conference last week! It takes a great team to pull off a successful event. Several individuals were very helpful to me with the pesticide certification trainings; I’m grateful to each of you for your help! Grateful for all the farmers who attended and it was great to catch up with several of you!
Crop Production Clinic Clarification: Both commercial and non-commercial applicators in the ag plant and research and demonstration categories can renew at any of the crop production clinics. The York clinic is reformatted compared to the other clinics, but recertification can be received at any CPC. You can pre-register or walk-in that day for same cost. Info: https://agronomy.unl.edu/cpc.
This week I’ll share on soybean production studies. Our on-farm research update with farmers sharing their results will be Feb. 15 at the Holthus Convention Center in York. Pre-registration at: https://go.unl.edu/3j8q. Grateful for all the cooperators who work with me via on-farm research!
Soybean Seeding Rates: A first-year cooperator from the Utica area chose a soybean seeding rate study of 100,000 vs. 130,000 vs. 160,000 seeds/ac. He planted April 18 with NK 28-T3XF strip-tilled into corn. I started emergence counts May 9 when cotyledons had pulled just above the soil surface. 68% of the 130K, 52% of the 160K, and 48% of the 100K had emerged on Day 1. By Day 9 when I took the last counts, 95% of the 160K, 93% of the 130K, and 94% of the 100K had emerged. The May 22 frost with heavy residue reduced stands in areas of the field down to 35,000 plants/ac. The farmer decided not to replant a large portion of the field including where I had taken these initial emergence counts. This field missed the June 14 hail. The data shared doesn’t include the areas of the field down to 35K. At harvest, 81% of 160K (129,000 plants/ac), 79% of the 130K (103,000 plants/ac), and 86% of the 100K (86,000 plants/ac) remained. There were no yield differences with the 100K yielding 71 bu/ac, 130K yielding 72 bu/ac, and 160K yielding 73 bu/ac. The study results follow 17 years-worth of on-farm research results showing no yield loss when reducing seeding rates of 160-180K down to 120-140K in heavier textured soils. Our Nebraska data also shows that soybean planting rates of 80,000 to 120,000 seeds/ac resulted in the highest profitability.
Soybean Maturity Studies: Seth Naeve, University of Minnesota shared that compared to lower yielding varieties, highest yielding varieties produce between 20 to 40% greater yields. Thus, variety selection is the greatest factor for impacting soybean yield. Third-party information is limited in Nebraska. If there’s interest in a soybean grower plot in the area (particularly someone willing to host this), please let me know. Some third-party resources include: F.I.R.S.T Soybean Testing Program (https://www.firstseedtests.com/), and data from Universities such as Iowa State, K-State, South Dakota State, and Missouri. Seed companies have numerous locations with data. When possible, look at how a variety performs over multiple years at multiple locations.
We now have 13 site-years worth of data from Seward and York counties comparing Group 2 and Group 3 maturity soybeans. Reasons for considering a Group 2 variety in our area include spreading out harvest, opportunity for planting cover crops for greater fall growth, and spreading risk from weather events. In 10 of the 13 site-years, there were no yield differences between high-yielding Group 2 and 3 varieties when planted mid-April to early May. In the other three site-years, the Group 3 varieties had higher yields than the Group 2 varieties. One reason was late season rains benefited Group 3 soybeans in non-irrigated environments in two site-years. In the gravity irrigated ridge-till environment, harvesting the Group 2 variety sooner may have helped reduce plants from lodging down into furrows that are difficult to pick up at harvest.
Freeze Events: With last week’s cold spell, it’s hard to know exactly how it will impact flowering trees, shrubs, and fruit trees. It really depends on the bud/flowering stage at the time of the freezing temperatures. I’ve also received a number of questions regarding wheat and how bad it looks due to frost right now. In some cases, the injury may look worse due to leaf burn from fertilizer and/or fertilizer + herbicide applications shortly before the freeze events. We need to be patient and allow time with anticipated warmer temps to watch recovery. Ultimately, wheat in the tillering stage is quite tolerant of frost with minimal yield impact expected down to 12F for 2 hours. Once the wheat begins jointing (growing point moves above ground), temperatures like what we experienced of 24F for 2 hours can moderately to significantly impact yield. While upper leaves may be burned off from frost, there’s actually a micro-climate effect within the wheat canopy which is warmer closer to the ground (depending on the wheat stand). If the soil had quite a bit of moisture prior to freeze events, it also helps buffer the soil temperatures, reducing freeze injury. What I look at: is the wheat in tillering or jointing stage? Do you notice any splitting of tillers at the base of the plants? If the wheat is jointing, split the stem to look at the growing point (I use a box cutter for wheat this small). Is the growing point white and healthy or yellow/brown and mushy? Wheat can tolerate much, but I can also appreciate how many of you are trying to make decisions. You can also check out the freeze to wheat article in CropWatch and more localized to our area, Nathan Mueller’s blog: http://croptechcafe.org/multiple-spring-freeze-events-impact-winter-wheat/.
Regarding alfalfa, it’s another ‘wait and see’ situation. Please see this week’s CropWatch
at cropwatch.unl.edu for more info. The more growth actually results in potential for increased damage and it also depends on the air temperature and duration of freeze. New seedlings can be pretty resilient due to being close to warm soil, protected by companion crops like oats, or due to natural seedling tolerance. Damage can range from upper stems and leaves wilting and turning brown to a hard freeze causing plants to completely wilt down and fall over. What I watch for are new buds…buds that are within the canopy that weren’t exposed to frost, new axillary buds that develop from upper stems that have frozen off, and new crown buds. In 2007, some chose to remove the dead plant material from the plants to stimulate growth. Dr. Bruce Anderson found the plants reacted to the killed tops from frost the same as they would from a normal cutting. Thus, we’d recommend observing how the alfalfa responds and ultimately doing nothing for the time being. Cutting alfalfa for hay with only 6” of growth in most fields wouldn’t be practical and can weaken plants. Anticipate first cutting to be delayed as a result of these multiple freeze events.
Planting: While you might not share this sentiment, I was grateful last week was so clearly not the right conditions to plant for this area of the State! It seems extra tempting when there’s a couple of really nice days prior to a cold snap. Outside of ‘is it ok to plant’ or ‘should I plant corn or beans’, my main planting question is regarding soybean seeding rates. We now have 13 years of on-farm research from this part of the State in 15” (planted not drilled) and 30” rows in silt loam/clay loam soils showing no yield benefit to planting greater than 120,000 seeds/acre. These studies included a seed treatment when soybean was planted in late April/early May. Otherwise, no yield differences were achieved from 120K to 180K regardless if seed treatment was used. We share more in this week’s CropWatch. With sudden death syndrome being bad in 2019, I’ve also received questions on seed treatments such as Ilevo® or Saltro® for it. I will share the research next week. Bottom line: economically I would only consider this if you have a history of SDS. Even so, environmental conditions don’t always favor SDS. You could consider using SDS treated seed along areas with a creek or intermittent stream running through the field or lower areas of the field where water ponds and using non-SDS treated seed in the rest of the field. Early planting doesn’t automatically favor SDS. Water during flowering and levels of soybean cyst nematode can favor it. Will share the data next week. And, a reminder to check your seed tag regarding proper PPE to wear when handling any treated seed. Here’s wishing you a safe planting season!
Reducing Soybean Seeding Rates: Can I reduce soybean seeding rates and still maintain yield? It’s a common question from soybean growers, especially those seeking to reduce input costs. Every year during winter meetings I share what our growers have found. We now have 11 years of On-Farm Research proven data.
The findings? Reducing soybean seeding rates from 180,000 or 150,000 seeds/acre to 120,000 seeds/acre doesn’t statistically reduce yields in 30- or 15-inch rows in silty clay loam and silt loam soils in south-central and eastern Nebraska. Results of 18 studies showed for seeding rates of 180K, 150K, and 120K seeds per acre, average yields were 69.0, 68.7, and 68.4 bu/ac, respectively (Figure 1). The early studies within this dataset all had seed germination of at least 90% listed on the seed bag. In all but two situations (seeded at 180,000 and achieving 88% germination), the growers were able to achieve 90% or greater of their planted stand.
As I share this data, I’ve often heard “but I seed higher rates because of X, Y, or Z…”; however, this dataset includes a lot of those reasons without negative yield consequences! I’ve worked closely with these studies in walking the fields; taking notes and pics; counting plants, pods, and seeds; so I’m really confident of the research and the fact that soybeans truly compensate for reduced populations! Outside of this research, I’ve also observed this in many soybean hail, crusting, and PPO inhibitor seedling damage situations. This dataset includes:
- The latest soybean varieties as the research was conducted from 2006-2017.
- Erect and bushy type varieties in growth architecture.
- Higher and lower yielding situations.
- Fourteen irrigated fields and four non-irrigated.
- Hail events occurring from cotyledon stage to R2 in some of these fields.
- Crusting in some non-irrigated fields.
- Seed treated in some fields and others without (determined by grower’s planting date).
- In some years, pod and seed count data were also collected; the data showed similar numbers of seeds/acre and ultimately yield per acre.
- Observations of increased plant branching at lower seeding rates and difficulty in telling the seeding rate treatments apart as the season progressed.
Our research data for 11 years shows no statistical yield differences in seeding rates from 120,000-180,000 seeds/acre in 15- or 30-inch rows in silty clay loam or clay loam soils. Thus, reducing seeding rates is a way to consider reducing input costs for 2018 without impacting your yield. If you dropped your seeding rate from 150,000 seeds/acre to 120,000 seeds/acre, you could save $10.08/acre, assuming a yield loss of 1 bu/ac, a seed cost of $60 per 140,000 seeds, and a savings of $25.71/ac on seed.
- Thus, if you plant between 140,000-160,000 seeds/acre, consider dropping your seeding rate to 120,000 and aiming for a final plant stand of 100,000 plants/ac based on our research findings.
- If you plant at 180,000 or more seeds/acre, consider dropping your seeding rate to 140,000 seeds/acre as a step-wise increment.
Still hesitant? Consider trying this yourself for your location! Consider using either this Two Population Treatment Design or Four Population Treatment Design. You also can download the Nebraska On-farm Research app, available in Apple and Android, to help you set up your plot design to obtain scientific results. If you have questions or need help setting up your research project, please contact me or anyone involved with our Nebraska On-Farm Research Network. To view all the graphs and additional data regarding 15″ row spacing with reduced seeding rates, please check out this week’s UNL CropWatch at http://cropwatch.unl.edu.
Beginning Soil Moisture: On Good Friday, I installed soil moisture sensors down to 4′ in non-irrigated no-till fields at Bladen and Lawrence. Last week I added three more sites at Clay Center, Superior and Byron. Thus far, the 3′ and 4′ are dry in all those locations other than Clay Center (only dry at 4′). At Superior, I could only get the soil probe in the ground 6″ into actively growing rye and 1′ in cover that winter-killed. I was just curious what kind of moisture existed currently in the southern tier of counties. I realize planting plans are in place and that we often receive rains in April/May. Hopefully it provides information that can be helpful in how to use that soil moisture. If we don’t get necessary rains, you may consider switching to a different crop, growing feed if you have cattle, or not terminating actively growing rye as originally planned but perhaps using it for feed. Will share graphs next week and I appreciate the growers allowing me to install these in their fields!