Planting Considerations: This email newsletter reaches a wide area of the State, so soil temps vary quite a bit and some of you may be in better planting conditions than others. We still recommend planting into soil temps as close to 50°F as possible, check weather conditions for next 48 hours to hopefully maintain temps 50°F or higher, and avoid saturated soil conditions. If planting a few degrees less than 50°F, make sure to check with seed dealers on more cold-tolerant seed. This is most likely common sense, but I still feel worth mentioning. Everything we do at planting sets the stage for the rest of the year. We’re blessed to have equipment that can allow for many acres to be planted in a short amount of time. And…we also have the ability to mess up a lot of acres in a short amount of time.
Planting depth is also key. Aim to get corn and soybean in the ground 1.5-2” deep. This is critical for correct root establishment in corn to avoid rootless corn syndrome. Rootless corn syndrome is when the nodal (crown) roots don’t get well established and successive brace roots can’t establish either. This allows the seedling to whip around in the wind, potentially being dislodged, become weak or die. With center-fill planters, when adjusting down-pressure on the go, sometimes the planter ends may not always be seeding as deep as the center. Too often I’ve seen that resulting in seed 1” or less and the field pattern can be observed the entire growing season with potential yield impacts. So don’t just rely on the monitor. Take the time to dig up seed behind the planter and at spots along the whole planter length to ensure the proper seeding depth. And do this with every field, particularly with different tillage/residue situations. I realize this takes time, but you’ll be glad you did to catch any issues before too many acres are planted incorrectly.
With cold temps or higher soil moisture conditions, it’s still important to get that seed at least 1.5-2” in the ground. Planting 1.5-2” deep helps both corn and soybean to have that seed in even soil temperature and moisture conditions. You may be surprised on that recommendation for soybean, but I think it’s even more critical with planting early. In fact, UNL research near Mead compared planting depths of 1.0, 1.25, 1.5, 1.75, 2.0, 2.25, and 2.5 inches in 2011 and an additional planting depth of 2.75 inches was added in 2012 and 2013. The study found lowest yields when soybean was planted 1.25” or less or 2.25” or greater with the highest yield at 1.75” deep. One of that study’s hypotheses was that planting deeper would buffer soil temperature and moisture and protect newly emerged seedlings from frost and freeze damage, particularly when planting early in the season.
Hopefully planting soybean early is still something you’re considering for this year! We wrote a CropWatch article this week at http://cropwatch.unl.edu to provide some updated research on amplifying the effects of planting early. There’s so much research regarding how early soybean planting increases yield that we wanted to share new research regarding maturity groups, etc. Essentially, what it appears from the research thus far, is that it’s more important to choose a consistent, high-yielding soybean for your area, regardless of specific maturity group. We’d like to get more specific data and have on-farm research protocols available to compare MG2.4-2.5 vs. MG3.0-3.5 and Dr. Jim Specht would also like to collaborate with us on documenting various factors. Please let me know if you’re interested in this! There’s also a protocol for comparing early vs. late planting of soybean.
Soil moisture conditions didn’t improve this week at the six sites I’m monitoring in Webster, Nuckolls, Thayer, and Clay counties. You can find the chart comparisons on my blog at http://jenreesources.com. Last weekend’s bizzard didn’t provide significant moisture in this area. With pastures slow with growth and drought increasing in Kansas, discussions with farmers have included cover crop termination, grazing rye that’s had anhydrous ammonia applied to it (with the original intention of termination and planting to corn), and grazing wheat. Most of these topics are included in this week’s UNL CropWatch at http://cropwatch.unl.edu. The articles are too long with too many considerations for me to add them in this news column, so please do check them out if you’re interested in these topics. Another topic I’ve had several questions about is regarding how temperature and rain affect burndown herbicide applications. Dr. Amit Jhala, Extension Weed Specialist, addresses that in this week’s CropWatch as well, so please check that out. Here’s wishing everyone a safe planting season with conditions to get #plant18 and #grow18 started off well!
Well, winter seems to be sticking around. My thoughts and prayers have been with those of you calving with the difficult conditions this year.
I provided an update regarding soil moisture status in non-irrigated fields both in this week’s UNL CropWatch at cropwatch.unl.edu and my blog at jenreesources.com. We’ll see what happens with moisture in the next few weeks and I’ll post updates to my blog.
Very few have tried planting in this part of the State that I know of. Grateful for all of you who keep me updated on what’s going on through your questions and comments! In this week’s UNL CropWatch, Dr. Roger Elmore took the lead on an article addressing corn planting. The message is to ideally wait till soil temperatures reach 50F with weather conditions allowing soil temperatures to remain at 50F or higher for the next 48 hours. We’ve observed when seed was planted and a cold snap with cold rains was received within 48 hours, some problems with seed germination and emergence. Hybrids vary in cold tolerance and seed companies are a great resource for that information as to which hybrids could be planted first in colder soils. Soil temperature information can be found at the UNL CropWatch site at: https://cropwatch.unl.edu/cropwatchsoiltemperature. We’d also recommend you take the soil temperature in the field before you plant and can do so by using a meat thermometer.
Last year I remember receiving questions from April 21-24 regarding planting corn and soybeans with an anticipated cold snap later that week. At that time, I was recommending growers switch to soybeans. The reason? Soybeans imbibe (uptake) water more quickly than corn seeds and while we hear 48 hours to be on the safe side, the critical period is more like 24 hours. Also, several years of both small plot and on-farm research in Nebraska has shown the primary way to increase soybean yields is to plant early. Dr. Jim Specht’s research showed soybeans produced a new node every 3.75 days once V1 occurs. The nodes are where pods and seed occur. Our on-farm research planting date studies also showed regardless if the spring was cold/wet or warm/dry, the early planted soybean always out-yielded the later planted with a total average across trials of 3 bu/ac. The data ranged from 1-10 bu/ac. We never planted early without using an insecticide/fungicide seed treatment to protect that seed, so we recommend you add that if you do plant early.
Our recommendation would be to plant the last week of April or as close to May 1 as conditions allow. We’ve also seen good results after April 20 in years if the soil temperatures were around 50F with good weather conditions at least 24-48 hours after planting to maintain that soil temp. It’s important to know your level of risk, though. Crop Insurance planting date for replant considerations is April 25 and there may also be replant options from your seed suppliers. We never replanted any of our studies and I have only observed frost on soybean cotyledons one year where growers planted early with soybeans coming out of it. We had the largest number of acres I’ve seen planted by April 24 last year with thankfully no issues and they were able to take advantage of a high-yielding bean year. Perhaps this is something you wish to try for yourself this year? Consider planting some passes of soybeans early and come back with some passes three weeks later. You can use this Soybean Planting Date Protocol if you’re interested in trying this for yourself. Please let me know if you’re interested in this!
Depending on the number of acres you have, some growers are now planting soybeans first. Others are planting corn and soybeans at the same time by either running two of their own planters/drills or custom hiring someone to plant soybeans for them. This also spreads risk and can help with harvest. Regarding maturities, a study conducted at UNL East Campus compared a 2.1 vs. 3.0 maturity group variety at 10 day intervals beginning April 23 through June 19. Yield was highest for early planted soybean and a yield penalty of 1/8 to 1/4 bu/ac per day of delay in planting for MG2.1 and MG3.0 varieties, respectively was found. The study also indicated that yield of the MG3.0 variety was higher relative to the MG2.1 variety in early plantings (late April and early-mid May), but the opposite (greater yield in MG2.1 versus MG3.0 variety) was found for late plantings (late-May and June). In our part of the State, we’ve observed really high yields from strong genetics in the MG2.4-2.5 varieties when planted early; so I have a hard time automatically recommending later MG varieties without more data. Thus, I would love to work with anyone interested in planting early comparing a high yielding MG2.4-2.5 vs. a high yielding MG3.0-3.5 to obtain more data. Here’s a Soybean Maturity Group Comparison with Early Planting protocol to consider and please let me know if you’re interested in this!
Wheat: My colleague, Dr. Nathan Mueller in Dodge County, has taken the lead on
sharing wheat information for Eastern Nebraska. He’s put together an excellent resource on his blog at http://croptechcafe.org/winterwheat/. Every Friday he’s sharing an update called “What’s up this Wheat“. He also started an Eastern NE wheat listserv and his website explains how to subscribe to it. Grateful for his effort in this as we both have goals of increasing crop diversity in the areas we serve and there are many benefits to wheat in rotation!
Crabgrass prevention in Lawns: Just a quick note that while our Extension lawn calendars promote applying crabgrass preventer in mid-April, our horticulture experts say to wait till soil temperatures are 55F on a seven day average and we are currently far from that! Check out https://cropwatch.unl.edu/cropwatchsoiltemperature for soil temp info.
As I set here writing, we went from wearing t-shirts yesterday to receiving freezing rain and sleet today! The precipitation is much welcomed and it’s nice to see spring bulbs coming up and the grass turning green! But we’re unfortunately not out of the woods yet regarding this drought, and may not be for some time.
This Thursday, April 11, Elizabeth Killinger, UNL Extension Educator in Hall County, will be talking to us about gardening during drought. Come enjoy an evening of learning about drought-tolerant plants and ideas for your landscape! The evening begins with a light supper at 5:30 p.m. and we plan to be finished around 7:00 p.m. There will be no charge for this workshop, so please come and invite your friends and your youth who enjoy gardening as well!
Also, if you would like to bring some plants for exchange, you are welcome to do so and share with others! Please call the Clay County Extension Office at (402) 762-3644 or Jenny at firstname.lastname@example.org to let us know you’re coming so we can plan for the meal. See you then!
UNL Extension’s CropWatch newsletter has featured several wheat articles from Bob Klein, UNL Extension Cropping Systems Specialist and other Extension faculty. Since they’re on several different CropWatch release dates, I decided to put all the info. in one place for you. Hope this helps!
For those who have waited to plant winter wheat, Bob Klein, UNL Extension Cropping Systems Specialist, says to increase wheat seeding rate 10-15 lbs per acre (150,000-225,000 seeds/acre) per week for every week delayed after the seeding rate for our area. Hessian fly free seeding dates range from September 25 for most of our area to September 28 in southern Nuckolls and most of Thayer Co.
For no-till, he recommends automatically increasing seeding rate an additional 50%. So if you’re a dryland no-till producer planting in October, he would recommend seeding 90 lbs to 120 lbs maximum of wheat seed. For irrigated wheat, start at at least 90 lbs/ac and increase 15-20 lbs/acre every week later than suggested seeding date but don’t exceed a maximum of 180 lbs/acre of seed.
A review of seedling rates vs. yield potential: On the average, there are 22 seeds per head and 5 heads per plant, or 110 seeds per plant. With an average seed size of 15,000 seeds per pound or 900,000 seeds per bushel, a pound of average-sized seed with 80 percent germination and emergence has a yield potential of approximately 1.5 bushels per acre. Seeding 40 lb of seed with a weight of 15,000 seed per pound has a yield potential of 60 bushels per acre.
Paul Jasa, UNL Extension Engineer says to make sure the drill is running lower in back than normal. Transfer more drill weight to the back of the drill and add extra weight to the drill. This will allow for penetration into dry, hard soil, forcing the seed into the soil and insuring seed-to-soil contact. Also, don’t seed wheat too shallow. When using disc drills, plant at a depth of 2 inches or more.
- Fertilizer Options for Dryland Wheat: Is Wait and See a Good Option?
- Grasshopper Management Considerations in Emergent Winter Wheat
- Use of Seed Treatment Fungicides to Improve Wheat
- Guides to Winter Wheat Variety Selection
- How Wheat Seeding Date Affects Yields
- Assessing Winter Wheat Stands and Estimating Yield Potential
Increasing input costs are forcing producers to evaluate every decision they make. With soybean seed costs on the rise, producers in the Greater Quad County On-Farm Research group wondered if they could reduce their soybean populations while maintaining yield and saving money. On-farm research conducted in field scale, randomized, and replicated farmer plots and at the South Central Agricultural Laboratory near Clay Center from 2006-2008 proved producers could.
Since 2006, planting rates of 90,000, 120,000, 150,000, and 180,000 seeds per acre have been planted in 12 irrigated soybean fields on 30-inch rows. Prior to this research, most of these producers usually planted 160,000-180,000 seeds/acre. The 90,000 low rate was determined based on UNL research recommending not to replant a hailed soybean stand if at least 90,000 plants/acre remained in the field.
In 2008, cooperating producers used these same rates to plant soybeans at five sites with 20 replications. Planting dates ranged from April 29 to June 3. In the end, there was little difference in percentage stand and yield among the four planting rates (see Table 1). The 120,000, 150,000, and 180,000 yields were statistically the same (only a 0.3-bushel difference between the 120,000 and 150,000 rates) and were significantly better than the 90,000 seed-per-acre plots; however, note that the 90,000 plot yielded only 1.7 bu/ac less than 150,000 plot. All data was statistically analyzed to determine the yield differences due to the various treatments.
The findings are similar to the 2006 and 2007 studies. In 2006, yield results ranged from 65.5 bu/ac at 90,000 to 67.4 bu/ac at 180,000. In 2007 yield results were 59.4, 59.6, 59.4, and 60.2 bu/ac for 90,000, 120,000, 150,000, and 150,000 respectively with no statistical difference.
Most likely, these results are indicative of soybean’s ability to compensate for reduced populations. Figure 1 shows increased plant branching at lower populations compared to less branching at higher populations. This was observed in all fields regardless of variety. Also observed in 2008, were two additional nodes/plant at the 90,000 population compared to the 180,000 population. Nodes are important as flowers, pods, and ultimately yield are produced from them.
A dryland field in Nuckolls County also showed interesting results. This field was hailed at the cotyledon stage, so planted populations of 100K, 130K, and 160K became average actual stands of 74,417; 89,417; and 97,917 plants per acre. August rains in 2006 helped deliver yields of 38.6, 40.6 and 42.7 bu/ac, respectively.
Figure 1a. Lower planted populations of 120,000 compensated for reduced plants by increased branching, flowering, and pod set, regardless of typical variety architecture.
Figure 1b. Fields with planted populations of 150,000 were observed having a more erect architecture with reduced branching compared to fields planted at rates of 120,000.
Rates for Drilled Soybean:
In 2006, one drilled field in irrigated conditions in Fillmore County yielded 68.4 bu/ac, 66.6 bu/ac, and 67.2 bu/ac for planting rates of 150,000, 175,000, and 190,000 seeds per acre respectively. Another study in 2006 conducted by the Soybean Feed Grains and Profitability Project in a rain-fed field in Lancaster County showed a slight but significant yield advantage to drilling soybean at a rate of 152,500 seeds per acre compared to 115,000 seeds per acre. Yield for the higher seeding rate was 56.8 bu/ac compared to 56.0 bu/ac with the lower seeding rate. When using grain drills and reducing soybean populations, variable seed spacing and seed depth within a drilled row can be an issue for soybean emergence. This is why a population increase for drilled beans is often recommended.
Recommendation: Plant Soybeans at 120,000 Seeds/Acre
Based on three years of consistent research results, UNL specialists recommend reducing planting populations from an average of 160,000 seeds/acre to 120,000 seeds/acre in 30-inch rows. This reduction of 40,000 seeds per acre results in a savings of $10.66 to $18.57 per acre based on seed costs of $40-65 a bag. For three years producers were able to achieve a 90% stand and have not seen a statistical yield variance from 150,000 or even 180,000 seeds/acre. With soybean seed costs increasing, reducing soybean planting populations is another way producers can survive high input costs of crop production.