Thanksgiving and Gratitude
For 20.5 years I’ve been writing news columns and sharing them each Sunday night under the name JenREESources. It was a play on my name and Deanna Peshek, the Clay County Office manager at the time, helped me develop the creative branding.
Several have asked what I’m going to do with my name with my recent marriage. My email and blog will come from Jenny Brhel and the branding as JenResources (but my website url will remain the same). I’m truly honored and humbled with all the information available that there are people who choose to read what I write!
Gratitude: With Thanksgiving this week, I just find myself extra grateful for the blessings God has given me in life. Some of those blessings are my new husband Brian, our families, and all the people who have spoken into our lives and walked alongside of us. We all go through brokenness of some type at some point in our lives. I’m grateful to God for all He brought me from, through, and to where I am today, for the healing, for the flourishing.
Those of you who’ve read my column for awhile know that Thanksgiving is my favorite holiday, yet I’ve seen the importance and seek to live with gratitude, albeit imperfectly. I wasn’t too grateful for a difficult situation this past year and had to dig deep to find some gratitude in it, but there is always something if we allow ourselves to choose a different mindset. As I talk with and walk alongside of people, it seems like there’s increasing fear, anxiety, stress. For encouragement, Fear and Anxiety can’t succeed in the midst of Gratitude. Gratitude produces Joy! Taking time to write or say aloud something you’re thankful for in the midst of fear or anxiety is a great way to change one’s mindset! So, this Thanksgiving, no matter how difficult the circumstances, may we seek to find Gratitude in the many ways we are blessed. May we then seek to live with gratitude and joy in our lives no matter the difficulties we each face!
Thanksgiving Food Safety: Interesting fact, the day after Thanksgiving is the biggest food borne-illness day of the year. Nebraska Extension continues to do their part to help our clientele remain heathy and have good food safety practices. The following are from Extension Educator Cindy Brison and our Food Safety Team. We also have this information available in Spanish.
One of the most frequently asked questions around Thanksgiving is “How do I thaw a frozen turkey?”…including on Thanksgiving morning! The answer to this question is an important step in meal prep for food safety. Unsafe handling and undercooking the turkey can cause foodborne illness. For information on thawing your turkey and more: https://food.unl.edu/how-thaw-turkey
Do not wash or rinse your raw turkey! Avoid washing or rinsing a turkey (or any eggs, meat or poultry products for that matter) before cooking. Juices can transfer bacteria onto kitchen surfaces, other foods and utensils. If you must wash or rinse your turkey because of brining or other marinating processes, be sure to thoroughly clean and then sanitize all kitchen surfaces to eliminate the risk of cross-contamination. For more safety tips: https://go.unl.edu/washingturkey
Reminder: Cash Lease Workshop in York from 10:30 a.m.-2 p.m. (no charge and meal included thanks to Farmer’s National) on Dec. 3 at the 4-H Bldg. in York. RSVP: 402-362-5508.
Also Dr. Kohl is at the Bruning Opera House at 1 p.m. on Dec. 3 (no charge).
Sharing as one of my favorite songs-Have a blessed Thanksgiving!
JenREES 11/10/24
York Co. Corn Grower Plot Results: Special Thank You to Doug, Jason, and Karah Perdue for hosting the York Co. Corn Grower Plot this year! The results are located at: https://jenreesources.com/2024/11/08/2024-york-co-corn-grower-plot/ or can be obtained from the York Co. Extension Office. Congratulations to Dekalb with DKC 114-42 winning the plot at 289.4 bu/ac!
Out of the Office: I’m excited to take some time off, including for my wedding! I won’t be answering questions till I return November 18. You are still welcome to please reach out to your local Extension office with questions and the office staff will direct you to a colleague who can help.
Dr. Kohl at Farmers/Ranchers College Dec. 3: This year Farmers & Ranchers College will kick off December 3rd featuring Dr. David Kohl. Registration will start at 12:45 p.m. and the program will start at 1:00 p.m. at the Opera House in Bruning, NE. The program is titled, “Economic Realities in the Agricultural Industry: The Pulse.” What economic realities can we expect to see in the global and domestic agricultural industry? Dr. Kohl keeps a pulse on trends and factors to be mindful of during the economic downturn. Some of these topics are land and machinery values, interest rates, concentration of agriculture, importance of cash flows, non-financial factors and much more.
Many to the area are very familiar with Dr. Kohl, but if you are not, here are some details about him. Dr. Dave Kohl is an academic Hall of Famer in the College of Agriculture at Virginia Tech, Blacksburg, VA. Dr. Kohl has keen insight into the agriculture industry gained through extensive travel, research, and involvement in ag businesses. He has traveled nearly 10 million miles; conducted more than 6,500 presentations; and published more than 2,250 articles in his career. Dr. Kohl’s wisdom and engagement with all levels of the industry provide a unique perspective into future trends. Don’t miss this high energy session in preparation for 2025!
Big Questions and Innovative Solutions in Land Management is a series of workshops being presented throughout the State for farm and ranch landowners, landlords, and tenants who want to learn more about current trends in farm or ranch real estate, and best practices for managing or leasing land.
Topics include evaluating current trends in land values and cash rents, lease provisions and legal considerations, proper communication strategies and considerations for successful land transitions. Workshop participants will also be able to find answers to common farmland leasing and land ownership questions. The program is free to attend but registration is required by calling the phone number at the location you desire to attend.
Nov. 19 in Kearney: 9 a.m.-noon CT at the office of Nebraska Extension in Buffalo County, 1400 E. 34th St. Register by Nov. 18 at 308-236-1235.
Dec. 3 in York: 10:30 a.m.-2 p.m. CT at the York County 4-H Building, 2345 Nebraska Ave. Lunch provided by Farmers National Company. Register by Dec. 2 at 402-362-5508.
Dec. 10 in Mead: 10:30 a.m.-2 p.m. CT at the office of Nebraska Extension in Saunders County, 1071 County Road G, Ithaca. Lunch provided by Farmers National Company. Register by Dec. 9 at 402-624-8030.
Dec. 12 in Wilber: 1-4 p.m. CT at the office of Nebraska Extension in Saline County, 306 W. 3rd. Refreshments provided by Farmers National Company. Register by Dec. 11 at 402-821-2151.
2024 York Co. Corn Grower Plot
Thank you to Doug, Jason, and Karah Perdue for hosting the 2024 York Co. Corn Grower Plot! Thank you to Fontanelle for providing the tester and Congratulations to Dekalb for the winner! Thank you to all the companies who support the Corn Grower Plot for the scholarships and ag literacy events we provide for youth!
Fall Nitrogen Challenge
It’s such a blessing to receive some moisture! With November here, sharing this week on nitrogen applications.
While the November 1 date that allows for fall fertilizer application to fields has arrived, we also recommend waiting to apply fall nitrogen till soil temperatures are below 50F. At that temperature, soil microbes are less active and less likely to convert ammonium to nitrate. Soil temperatures can be viewed at: https://cropwatch.unl.edu/soiltemperature. As I write this, the daily average 4” soil temperature is currently 55F with the weekly average at 53F.
Nearly a year ago, I shared my Nitrogen Challenge with you. I’m grateful for all the producers who gave that a try! Some who wanted to try it had applied too large a base rate before I had released the article, so sharing a reminder now.
My Challenge: The challenge is to everyone with irrigated ground who applies fall anhydrous or spring pre-plant fertilizer:
- Leave 1 piece of ground with a base rate of 70-100 lb N/ac.
- Apply the rest of the N in season as needed using a tool like Sentinel Fertigation that senses plant needs.
- Asking each grower to consider this for 1 field. Are you willing to join me in this?
I genuinely believe this is the primary way to change the nitrogen story both now and for future generations. Why? We can’t impact the legacy nitrate from previous generations that is impacting groundwater nitrate levels now, but we can impact the nitrate that remains in the soil after current nitrogen practices now.
Nitrogen rate is the most consistent thing I keep seeing in nutrient recommendations and on-farm research studies that we can adjust. I’ve shared On-Farm Research results from farmers’ fields in this part of the State on heavier textured soils showing there’s no one solution with nitrification inhibitors, nitrogen application timing, biological products. The most consistent thing I see is an opportunity around reducing nitrogen rates. I’m not saying there’s one solution. My challenge is around what I feel holds the most promise right now for irrigated ag in this area.
We can’t precisely know an amount of nitrogen to recommend for application to land using pre-plant soil tests and/or any nitrogen equation. They’re good tools. But, we don’t know how much irrigation will be applied in season nor how much mineralization will occur due to weather conditions. 2022-2023 were high mineralization years and 2024 was a low one. Soil agronomy needs biology in addition to chemistry and physics. That’s why I’ve been so supportive of the in-season sensing technologies where the plant tells us what it needs based on what is occurring in the soil. Project Sense was a UNL/NRD/Corn Board/USDA research effort using ground rig applications. I think it never took off because I’m unsure any Co-op or company took the idea on as a business. Would still be applicable.
The UNL pivot-based sensing research resulted in the graduate student forming the company Sentinel Fertigation. If there’s other companies doing this, please consider them too. There’s so much in ag we have to react to. Applying N in-season is also reactive. However, we can also be proactive in showing that farmers and agronomists locally want to keep looking for solutions to the nitrate problem by trying newer tools/technologies to see any impacts. Please contact me if you are willing to join me in this challenge.
Fire Damage to Fields
Reminder of the Fall Gardening Program this Saturday, Nov. 2, from 9 a.m.-Noon at the York County Fairgrounds (4-H Building). No charge. Registration is requested but not required to 402-362-6601.
Fire Damage to Crops and Residue: With the dry conditions and the fires that have occurred, I’ve received questions regarding the nutrient value in the residue and/or soil impacts in addition to what to do with unharvested crops that were impacted. Make sure crop insurance is contacted.
For corn that wasn’t harvested, if the ears are still attached to stalks, take ears from a couple worst parts of fields and also least impacted areas of fields (if that’s possible). It usually takes me about 4 ears to get a quart-sized ziplock bag full of shelled grain. Send the grain in to a lab (ex. Ward Lab, etc.) that will perform energy and protein analysis of the grain. I’ve found the grain analysis helps in situations where, at first, the elevators/ethanol plants say they won’t take the grain. We’ve often found the fires move so quickly in the field that the starch and overall grain quality is not impacted, in spite of the grain having some charred spots. If elevators or ethanol plants won’t take it, it has also been mixed in feed rations for livestock, which the grain analysis helps there too.
For unharvested fields with downed corn, depending on how charred the corn is and how much corn is down, many have chosen to disk up the field and then plant a rye cover crop. Grazing these fields has been done very carefully by strip grazing and if you plan on doing that, I will put you in touch with Dr. Mary Drewnoski. We also share more in this article: https://go.unl.edu/8hi2.
Plan on soil testing, which is wiser to do so next spring, to determine nutrient levels prior to planting. The combination of drought + fire may result in greater nitrogen availability than what one may think.
Fire can often aid grasslands, so would say to let pastures work to recover on their own for now.
For crop residue that’s burned, most nitrogen and sulfur in the residue are lost; however, the phosphorus and potassium are retained in the ash (as long as they don’t blow away).
Short-term nutrient loss from the residue is none to minimal. Research from the University of Wisconsin looked at the need to replace nitrogen to the succeeding corn crop when soybean residue was either removed or not removed. They found no difference in nitrogen impacts to the corn crop regardless if the residue was removed, thus there’s no need to replace the nitrogen in burnt soybean residue. Research from USDA-ARS in Nebraska, when looking at corn residue removal prior to corn planting, also suggested no need to replace the nitrogen lost from the residue. They found increased mineralization due to the change in C:N ratio when residue was removed. Previous research compiled in this resource from South Dakota State shared the same sentiments: https://openprairie.sdstate.edu/cgi/viewcontent.cgi?article=1365&context=extension_extra. The SDSU resource is also helpful when walking through a dollar value of other loss considerations.
Perhaps the greatest losses to consider are organic matter, soil loss, and soil moisture. Regarding organic matter, the soil holds the greatest portion of this. One year of residue is minimal, attributed with the potential of increasing organic matter 0.03-0.06%, depending on tillage type, crop, etc. Soil erosion due to wind/water can result in organic matter loss and loss of more productive soil. This is hard to quantify. Perhaps the more important factor is the soil moisture losses in no-till, non-irrigated fields, particularly in a dry year such as this. Paul Hay, Extension Educator emeritus, years ago shared with me several documented situations where yield losses due to moisture loss were estimated. Corn planted into burned no-till, non-irrigated soybean stubble ranged from 15-28 bu/ac yield loss in two situations. There was 0-3 bu/ac yield loss associated with soybean planted into burned, no-till, non-irrigated corn residue in two situations. Use of soil moisture probes can give an indication of soil moisture differences between burned and non-burned areas of fields or between fields. Direct yield comparisons between fields are difficult to make due to planting dates, hybrids/varieties, agronomic practices, etc., but important to still collect and assess.
We’ve observed in the past is that the ash on the soil is fairly hydrophobic after a fire event. Thus, even when rain occurred, it took several rains before the ash on the soil was disturbed enough for any rain to soak in. Because of this and to reduce soil loss overall, we recommend to get a rye cover crop drilled into the field. We found that the farmers who drilled in the cover and had enough moisture to eventually get it germinated and established in the spring were able to better grow crops in those areas the following year (these were non-irrigated fields). The fields and areas of fields where rye didn’t get established had poor crops the successive year, which was also a drought year.
Resources:
Fire Damage FAQ: https://go.unl.edu/8hi2
Fire Damage and Crop Residue Impacts: https://go.unl.edu/0wgq
Upcoming November 2024 Events
Sharing this week on upcoming November events. Please be safe with the remainder of harvest and we’ll keep praying for rain!
Fall Gardening Program: The Upper Big Blue Natural Resources District, USDA-NRCS, and Nebraska Extension are joining forces to present a fall garden workshop on Saturday, November 2, from 9 a.m.-12 p.m. at the York County Fairgrounds (4-H Building). This event is free to attend. Registration is requested but not required to 402-362-6601.
The workshop will include time to visit booths, speak with presenters, and enjoy refreshments from 9 to 9:30 a.m. Presentations will be from 9:30 to 11:30 a.m. From 11:30-noon, there will be time for Q&A with both presenters, gathering materials, and viewing demonstrations at presenter booths. A representative from the Nebraska Forest Service will also be on hand to answer your tree care questions. Ordering for the NRD’s Conservation Tree Program will kick off in November.
This event will feature Extension Educator Sarah Browning, who has presented at our gardening workshops recently, including one on vegetable gardening and another on fruit tree care. Browning will present a Solution Gardening session that focuses on “right plant, right place.” Which plants are best for shade/sun? How about sandy or wet soil? What if you have a wildlife problem? If something didn’t work as planned this past growing season, Browning may be able to shed light on why and help you create a new game plan for next year.
Learn about opportunities for small-scale and urban agriculture producers with Brach Johnson, USDA Nebraska State Urban and Small-Scale Agriculture Conservationist. The Natural Resources Conservation Service (NRCS) has technical and financial resources for urban dwellers to enhance their production system and protect our natural resources. Urban agriculture includes the cultivation, processing, and distribution of agricultural products in urban and suburban areas. Community gardens, rooftop farms, hydroponic, aeroponic and aquaponic facilities, and vertical production, are all examples of urban agriculture. Tribal communities and small towns may also be included.
Cover Crop Grazing Conference is being held Nov. 6th with registration and trade show from 8:30-9:30 a.m. and program from 9:30 a.m.-3 p.m. at the West Central Research and Extension Center in North Platte. This year’s theme is “Getting the Most Out of Every Acre”. This conference is designed for producers looking to enhance profitability and sustainability through innovative grazing systems. Topics and speakers include: Winter Grazing Opportunities with Annual Forages and Latest Findings on Using Cover Crops for Forage, by Dr. Bart Lardner, University of Saskatchewan; My Journey to Integrate Cattle on Crop Ground by Logan Pribbeno, Wind Glass Ranch; and Filling the Forage Gaps Using Cover Crops by Dr. Mary Drewnoski. Breakout session topics include: Tips for Selecting and Using Temporary Fencing and What You Need to Know About Planting Dates and Forage Production. There is a charge of $40 to attend. Registration is at: https://go.unl.edu/ccgc24.
Central NE Regenerative Ag Conference will be held Nov. 19th in Holdrege at the Phelps Ag Center. Program is from 8:45-4:30 p.m. (Reg. 8 a.m.). Featured speaker will be Rodney Saunders with NRCS in addition to farmer panels. More info. and registration at: https://www.cccneb.edu/agconference
Yield & Soil Impacts from Grazing Corn Residue
With pastures short on grass due to drought, it’s a blessing for producers to get cattle out on cornstalks. Sharing an update on long-term research showing no negative impacts to the subsequent yield or soil from cattle grazing corn residue.
Mary Drewnoski, et. al share on yield impacts, “Two studies were conducted to evaluate the effects of corn residue harvest on subsequent crop yields. In a long-term study (16 years), cattle grazing corn residue in the spring (February to the middle of April) or the fall (November through January) slightly improved subsequent soybean yields and had no effect on corn yields in an irrigated field maintained in an annual corn-soybean rotation at Mead, Neb. In a five-year study, fall grazing (December through January) or baling of corn residue had no effect on subsequent corn grain yields in a field maintained in continuous corn production at Brule, Neb. These data suggest that the grazing of corn residue in the fall or spring at or below UNL recommended stocking rates will have slightly positive or no impacts on subsequent soybean or corn yields.
The stocking rates utilized were consistent with UNL grazing recommendations, which result in removal of half the husks and leaves produced (8 lb of leaf and husk per bushel of corn grain produced). The corn yields ranged from a low of 186 bu/ac in 2004 to a high of 253 bu/ac in 2009, with a median over the 16 years of 203 bu/ac. Recommended stocking rates would have ranged from 2.1 to 2.9 AUM/ac with a median of 2.3 AUM/ ac.”
Dr. Mary Drewnoski wrote an updated Beefwatch article about soil compaction and grazing. “One of the most common concerns about grazing corn residue is that cattle will cause soil compaction. A long term grazing data (16 years) conducted at the UNL has shown no compaction when grazing in the fall or the early spring. In this long-term study, grazing did not impact soil nutrient content. This fits well with expected impacts given that cows in mid-pregnancy retain very little nitrogen, phosphorus or potassium. Thus, they excrete in manure and urine most of what they consume resulting in very little nutrients being removed from the land. With long term grazing there was an improvement in subsequent soybean and corn yields. This could have been due to the nutrient cycling being sped up as there is an increase in microbial biomass in the soil in the grazed areas.
More recently, a study was designed to test an extreme scenario for spring grazing. The thought was that if grazing was to cause compaction, it was most likely to happen when the soil is wet and thawed and when a high stocking density was used. The field was grazed at the recommended rate by starting in mid-February with 3 hd/ac for 45 days (normal stocking) or starting in early March with 9 hd/ac for 15 days (high stocking). Turn out of the higher stocking density groups was delayed until it rained to have the worst-case scenario. All groups were removed mid-March. There were some minor increases in bulk density (measure of compaction). The penetration resistance was also higher, and thus more down pressure had to be applied to get the soybeans planted. Down pressure applied at planting was 265 lbs in the non-grazed and 290 lbs in the grazed treatments. Much of the increase in penetration resistance is due to the soil having less cover and thus less surface soil moisture. The planting speed was also reduced due to the surface roughness. However, the subsequent soybean yields were still improved by grazing. While it is not recommended to graze late into the spring as this does have some downsides when it comes to planting, if cattle happen to be left out when a warm-wet spell occurs, there is no long-term damage to the land.
Overall, when managed correctly, grazing corn residue can be a win-win for both the crop and cattle producer. Want to see the data for yourself? Check out these Nebraska Beef Reports:”
Effect of Corn Residue Removal on Subsequent Crop Yields
Effect of long-Term Corn Residue Grazing on Soil Properties
Effect of Corn residue grazing or Baling on Subsequent Crop Yield and Nutrient Removal
Impact of Spring Corn Residue Grazing on Soil Physical Properties and Crop Yield
Dry September 2024
Dry Conditions: With the dry conditions, harvest has been rapidly progressing. Two weeks ago, soybeans had green stems with seeds that were drier than people thought. Last week, many were harvesting soybeans in the 7-8% range. For corn I’ve been hearing a lot of 13-15% moisture and a couple reports down to 11%, but still with good kernel depth and quality. There’s unfortunately nothing we can do about this other than prioritize which fields to harvest. We’re in a race against time and the low moisture is due to weather conditions and hybrid specificity.
I’ve never seen it so dry in September. Eric Hunt, Extension Meteorologist, showed that September 2024 was the driest September in Nebraska on record (132 years). He also shared there’s no relief in site moisture-wise with above-average temps till at least the latter half of the month.
The lack of relative humidity and precipitation, intense sunshine, higher temperatures, and wind have all led to the grain moisture loss we’re seeing (which can be as much as 0.8-1.0 percentage points/day). Dr. Bob Nielsen, Extension Emeritus Corn Specialist from Perdue shared, “It is not uncommon for grain moisture to decline more than one percentage point per day over a period of days when conditions are warm, sunny, windy and dry.” Research that he and others conducted back in the 90’s showed that when corn matures also impacts drydown rate. Corn that matured in late August had a daily average drydown rate of 0.8 percentage points per day while corn that matured in late September averaged 0.4 percentage points per day. The corn borer pressure on non-gmo hybrids and late season disease pressure on all hybrids also led to plants dying/maturing early.
Corn hybrid characteristics can also impact kernel moisture. Hybrids that have thinner or permeable pericarp layers (outermost layer of the corn kernel), are more subject to moisture loss and faster drying rates in the field. I’m unsure how one knows this characteristic though.
You can look for these other characteristics resulting in quicker drydown: lower husk leaf number and thinner husk leaf, how soon the husk leaf tissue turns brown, how well the husk covers the ear (less coverage allows for faster drying), how tight the husk is (as looser husks will increase moisture loss), and how fast the ear turns down vs. remaining upright.
Fire Conditions: With the dry conditions and low humidity, we have a high risk of fire potential. I’m grateful to Nebraska DOT for posting the fire danger on signs throughout the state as a reminder to those traveling. Hopefully that will help reduce cigarette fires. Please keep thinking safety including fire safety with harvest. Days like Saturday are days to take a break from the field. Have fire extinguishers with you and charged, disks at fields, blow out combines regularly. Roads are so dangerous with the dust; turn lights on when traveling in the daylight. Please be safe! Safety resources: Educational Resources | College of Public Health | University of Nebraska Medical Center (unmc.edu)
Cover Crops and Small Grains: With the dry conditions, I’ve heard of several semi loads of wheat returned and not planted in the southern counties I serve. It’s hard to know what to do, but if a small grain is part of one’s rotation (which I feel there’s many benefits of), I’d recommend to stay the course with planting the current rotation and evaluate the situation next spring. It’s something to also discuss with crop insurance. Regarding irrigated ground, I have been recommending to put on 0.5”, potentially with two shots if needed, for cover crops. This may seem like a waste of water, so my explanation. The covers are an investment for soil erosion loss, uptaking excess nitrogen, aiding with weed control next year, and/or for grazing. With no soil moisture, the low amounts of irrigation are to get seeds growing or keep seedlings alive for the time being.
Trees and Lawns: We also need to be deeply watering trees in landscapes. Push a screwdriver in the ground to determine wetting depth. Kentucky bluegrass is shallower-rooted and doesn’t take heat as well as fescue. However, bluegrass will go dormant without dying, whereas fescue, even though it’s deeper rooted and more drought-tolerant, doesn’t go dormant from drought-stress, so it can die. After bluegrass has reached three weeks of dormancy and fescue has changed color, it’s recommended to water 0.5”/week to keep both grass species from dying.
Soybean Seed Size-Yield Impacts
Soybean Seed Size and Yield: It’s been awhile since we’ve seen full pods throughout plants (instead of flat pods with shrunken seed) and I’ve also noticed more 4-bean pods on upper nodes of plants this year. It has been deceiving in that soybeans with greener stems and some leaves were right at that point of being ready to harvest in the 13-14.5% range. Now I’m hearing a lot of dry beans are coming out again.
For the most part, soybeans have been of good seed size and quality. There are areas where “bb’s” are being observed again. I’ve heard reports of this from producers in the non-irrigated portions of southern Seward county and Saline counties. In those situations, plants often held onto leaves and just died due to lack of moisture; however, the seed number is still allowing for decent yields. This made me think of information I shared last year from Dr. Jim Specht, Emeritus UNL Soybean Physiologist, so resharing.
During soybean reproductive development, three stages — R1-R2 (flowering), R3-R4 (podding), and R5-R6 (seed-filling) — occur successively during July and August in the growing season. Soybean yield is ultimately a function of two components: the harvested seed number (in terms of unit land area), and the seed mass (weight of the average harvested seed). Seed number is set during the R1 to R4 stages of flowering and podding, though abortion of pods or seeds in those pods can occur in the later R stages. Seed mass (i.e., size) is set during the R5 to R6 stages of seed-filling, as the seeds undergo enlargement until the R6 stage ends at the onset of the R7 (physiological maturity) stage.
Jim and colleagues conducted a 3-year study in the 1980’s looking at the drought-stress sensitivity of seed number and seed size during different R stages. It involved 14 Group 0-Group 4 soybean varieties using seven treatments — each consisting of a single irrigation application, but each treatment differed with respect to the R stage coinciding with the single irrigation event.
When the single irrigation was applied during flowering, they saw a substantial increase in seed number, yet also a lower seed mass compared to the control rainfed treatment. This indicated that when water stress is mitigated during flowering (but not thereafter), soybean plants will set more seeds, but also end up making those seeds smaller when water is not adequate thereafter. We normally don’t recommend irrigation during flowering to avoid disease onset. This year we had some rains with cloudy conditions during a portion of the flowering period. However, rains shut off for the most part after that. I think that’s why we’re seeing the smaller seed size with lots of beans in some of the extremely dry areas.
In contrast, when a single irrigation is applied during seed-fill (R5-R6), fewer seeds are set (and/or retained) due to prior water stress, but the mass of those fewer seeds is optimized due to the late-applied single irrigations that mitigate any coincident water stress.
They also found a response pattern coinciding with an irrigation event occurring at R3.5 and R4.5 (podding) that showed plants in that stage are conditioned to enhance seed mass while still increasing seed number to some degree. Irrigating at this stage resulted in the highest yields among treatments. Thus, why we typically encourage first irrigation of soybeans at R3 in our silt-loam soils. Additional research in the early 2000’s verified this.
The research also showed a full-season multiple irrigation treatment that resulted in maximized seed number, but seed mass was not increased beyond the increase achieved with single irrigation at R3.5. Thus, by irrigating all season (or in a season where rainfall provides no water stress), seed number (which is set before seed mass) is prioritized by stress-free plants relative to optimization. While the weather is outside our control, I hope this is helpful in thinking through this past year. For risk mitigation going forward, I think it shows the importance of planting varying maturity groups to help spread risk with variations in weather conditions each year.
The full articles can be found at UNL CropWatch: One contains a quick method to determine yields using seed size just prior to harvest. The other is about water stress timing.
For Alex Harrell from Georgia with the record breaking yield of 218 bu/ac in 2024, he mentioned aiming for large seed size. Based on this chart, assuming around 450 seeds per square foot, he’d be achieving around a 1500 seeds/pound seed size.
In 2023, Alex Harrell reported a record soybean yield of 206.8 bushels/acre in 2023, and he suggested that the harvested seed in field likely had a seed mass of around 1,675 seeds/pound. Thus, a large seed size with (doing the math) around 477 seeds per square foot on a plant population of 77,000 plants/ac.
JenREES 9/22/24
Harvest is here and it’s been wonderful to see some good yields thus far! I was not expecting what we’re seeing for non-irrigated corn yields with how dry it’s been. And, it’s wonderful to finally see good soybean yields again! So far, non-irrigated, depending on area, is going 50-70 bu/ac and irrigated is going 70-high 80’s. The beans are also beautiful in size and quality so far this year!
Harvest Safety: For all of us as we’re on the roads, please be alert and slow down. It’s also important to talk about safety with teens who drive. Key things for us all: don’t pass in any designated “no passing zones”. Also don’t pass within 100 feet of an intersection, bridge, or railroad crossing. Don’t assume a tractor is going to turn right (another reason not to pass within 100 feet of an intersection). I always appreciated how dad pulled off into the right-hand side of the intersection when on highways or paved roads if he wanted to make a left-hand turn in a tractor because one never knows what vehicles behind you will do.
It’s so dry and hard to see on gravel roads when there’s traffic. Please be safe, slow down/stop at intersections and railroad crossings, headlights on, and be watchful/slow down as you come up on slow moving vehicles. For our farm families, we know things happen so quickly so please think safety with machinery, watch for people and objects around you, watch for power lines, and take your time on machinery and bin steps. Brandy VanDeWalle, Extension Educator, shares additional info. on her blog: http://vandewalleviews.com/2024/09/13/harvest-safety-12/. Here’s wishing everyone safety and good yields this harvest season!
Tar Spot vs. Southern Rust: With corn leaves drying down, people are wondering about the black spots they’re seeing on leaves. Right now, the majority of what is seen is either southern rust teliospores or saprophytic fungi feeding on dead/decaying material. Both of those can make for a dusty harvest. I have photos on my blog showing differences again between southern rust teliospores and tar spot. Tar spot just has a totally different look and color of black compared to what southern rust looks like. Hopefully the photos help ease people’s minds as most of what is out there is southern rust.
UNL Beef Extension online learning opportunities: Nebraska Beef Extension has planned several online learning opportunities that cover a variety of topics (listed below). For more information and registration please visit https://beef.unl.edu.
- Increasing Feed Value of Grazed Corn Residue: Sept. 24, 10 a.m. – 3 p.m. (CDT)
- 2025 Beef Heifer Replacement Price Forecast: Sept. 26, Noon (CDT)
- UNL Heifer Development Center First Year Wrap-up: Oct. 2, 10 a.m. – 3 p.m.
- Cornstalk Grazing Fundamentals, Leases and Agronomic Impacts Webinar Series 7 p.m.:
- Oct. 8, Corn Residue Grazing Fundamentals
- Oct. 10: Grazing Leases, Prices and Finding and Renting Residue
- Oct. 15, Agronomic Impacts for Grazing Corn Residue
- Oct. 17: Producer Panel-Challenges and Opportunities
- Knowing, Growing and Grazing Grass: Oct. 14, 17, 21, 24, 28 & 31, 7:30 – 8:45 p.m. (CDT)
- Pasture, Rangeland, Forage Insurance for Livestock Producers: Oct. 24, Noon (CDT)
- Leveraging Genetics to Improve Profitability: Nov. 4 & Nov. 6, 6:30 – 7:45 p.m. (CDT)
- Cattle Cost of Production, part of the Ag Smart Money Week series: Nov. 4
- Fundamentals of Feeding the Cow: Nov. 11, 14, 18 & 21, 7:30 pm – 8:45 pm
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