Monthly Archives: April 2023
JenREES 4/30/23
Corn and Soybean Planting Periods: The flowers/trees have been beautiful in the midst of a cool, dry, windy spring. I’ve been thinking about planting windows a lot. Appreciate all who have communicated thoughts on planting. From these conversations, I feel there’s been a shift in thinking, at least for this part of the state, with more paying attention to cold snap windows. Also been a shift to planting soybeans earlier or at the same time as corn. But to show whether that’s true or not, can you please help me with a quick one question visual survey on planting: https://app.sli.do/event/eV5gr4ioSZiSQKabEwRheB? It’s not letting me embed it, so you’ll have to click the link.
From what I’m hearing, planting progress ranges. Some are completely done, some are done with one crop or the other; many will finish this week. Others (mostly non-irrigated) are just starting this week. Some are concerned about May planting and yield loss. The rest of this info. mostly pertains to corn with encouragement that data has shown corn yields not to drop off till after mid-May planting dates. The article links provide the hard data.
Dr. Jim Specht, Professor Emeritus of UNL Agronomy and Horticulture, put together an article we will hopefully release in CropWatch this week. He was using NASS Nebraska Corn and Soybean 50% planting progress in comparison with NASS reported yields. Two key findings based on 43 years of data are:
- Delays in the Nebraska corn 50% progress date that occur within the May 2 – 12 planting period do not have an appreciable impact on resultant corn yield.
- The Nebraska soybean 50% progress date has advanced by eight days from a 43-year mean of May 22 to an expected May 14 date for the 2023 season.
Dr. Roger Elmore, also an Emeritus Professor of UNL Agronomy and Horticulture, had shared a similar sentiment in a 2019 CropWatch article where he shared about planting windows for corn using UNL research and NASS data. He shared, “A planting window exists within which (corn) yields do not vary tremendously. That window starts to close after mid-May. Many factors in addition to planting date influence final yields. There is always a chance that late-planted corn may out-yield early-planted corn.” Dr. Bob Nielsen, Emeritus professor at Purdue University shares similar key points for corn in an article, “Early planting favors higher yields, but does not guarantee higher (corn) yields. Statewide averages for planting progress and yield are not strongly related. Planting date is but one of many yield influencing factors.”
Alfalfa Weevils: I haven’t checked alfalfa fields yet, but had been watching comments down in Kansas. Alfalfa weevil larvae had hatched in southern Nebraska and also at the research station near Mead. In spite of planting, be sure to monitor alfalfa fields.
Dr. Bob Wright, Extension entomologist, and colleagues share the following in a recent CropWatch article. “The larvae of alfalfa weevils feed on first cutting alfalfa as larvae, and adults (and sometimes larvae) feed on the regrowth after the first cutting. In the Panhandle and in the northern tier of counties, there may be two flushes of weevil larvae this spring, leading to regrowth damage after the first cutting. Observations indicate the cause may be due to significant survival of both adult and larval weevils.”
It basically takes 1-2 alfalfa weevil larvae per stem to reach the economic threshold with today’s alfalfa prices. Take 10 stems from an area of the field, cut at ground level and hit them on the inside of a bucket. Count the number of weevil larvae present (also make sure to unfurl the bud leaves as some stay trapped in there). Depending on how close you are to harvest, one can choose to not treat and just harvest the alfalfa field while watching the green up for potential need to treat then, or treat prior to taking first cutting if harvest is still a ways off and economic thresholds are met. Insecticides for alfalfa weevil control include those that are pyrethroids (active ingredient ends in “thrin”) and products containing indoxacarb (e.g., Steward).
JenREES 4/16/23
The April 12, 2023 Nebraska Drought Monitor shows 98% of Nebraska in moderate to exceptional drought (D1-D4). We will keep praying rain; it will rain again one day! There’s truly concern about the dry conditions due to lack of subsoil moisture. Those planting last week shared how conditions were changing with the winds making surface soil hard. A few colleagues and I put together the following info. about planting into dry conditions in CropWatch that I will share this week.
I didn’t talk about planting deeper last week, but for those asking, Bob Nielsen, emeritus professor at Purdue said corn can be seeded 2.5-3” deep if that’s where uniform soil moisture is located in order to achieve uniform germination and emergence. We don’t recommend planting soybean deeper than 2.5”.
In general, we would only suggest watering before planting if the planter needs higher soil moisture levels to work well. So, if the soil is too hard, too powdery or cloddy, it may be worth running the pivot. Another situation to consider pre-watering is if greater than 180 lb/ac anhydrous ammonia was applied in a strip with less than two inches of moisture received since application to help reduce ammonia burn to the corn. Otherwise, our recommendation is to run the pivot after you plant if needed.
The usual recommendation is not to run a pivot when temperatures are below 40 degrees. Last year, several pivots were operated below 40 degrees without problem, but keep in mind with low dewpoints the pivot can ice up when the actual air temperature is well above 32. So, if you do choose to run in these conditions, keep a close eye out for ice buildup, which can collapse the pivot.
Bare, powdery soils will seal over very easily from rain or irrigation, so keep an eye out for runoff problems even with fairly low application amounts. And make sure if you do irrigate that you put on enough to get water down to the moist soil below. This is particularly a problem with tillage or where fertilizer knives have been used and dried the soil out.
It’s important that herbicides are activated with 0.5- to 0.75-inch of rainfall or irrigation, preferentially within five to seven days after herbicide application. If moisture received is less than this amount, some herbicide products have the potential to remain on the soil for up to 14 days without being fully activated. We will have to see how the high winds blowing soil and removing soil particles containing herbicide impact future weed control.
For those who applied dry or liquid urea on the soil surface, particularly without the use of an inhibitor, irrigation of 0.5-inch can help with incorporating the urea into the soil and minimize urea loss. If irrigation is not available, an inhibitor was not used and no rainfall has been received within seven days, monitor the corn crop to determine if nitrogen deficiency occurs due to nitrogen loss.
John Mick, Pioneer agronomist, shared last year that water from irrigation wells in the southern part of the state often is around 50-53°F, with it slightly less in temperature as one moves north in the state. These temperatures are not a problem to be concerned with regarding any negative impacts to seeds imbibing water.
Lawns: For those struggling with lawn winterkill, Kelly Feehan shares, “Some lawns may come out of winter with dead areas in need of reseeding. While early September is the ideal time to seed Kentucky bluegrass and tall fescue, spring seeding success can be improved by seeding as soon as possible so seedlings establish roots before summers’ heat. Improve seed to soil contact by aerifying, power raking, and/or hand raking right before seeding. After seeding, a light raking will further mix the seed and soil. Water lightly and often to keep the seedbed moist. Mulch will help conserve water, but use lightly so at least 30 to 40% of soil is still visible through the mulch. Use low rates of fertilizer, about one-half to three-fourths pounds per 1000 square feet, applied every four to six weeks until mid-June; and keep the area well-watered all summer while avoiding overwatering which can lead to poor rooting and disease.” Also avoid crabgrass preventer to newly seeded areas.
Evaluating Wheat Stands handout by Nathan Mueller: https://croptechcafe.org/wp-content/uploads/2020/04/Evaluating-Winter-Wheat-Stands.pdf
JenREES 4/9/23
Each year is another opportunity to learn. The forecasted warmer temps for the coming week have many excited to be in the field. It feels so early for planting, yet I can appreciate the general warming trend for several days. My concern is when the low temps get back into the 30’s again. Seeking advice from multiple sources can be wise. It’s important to know your level of risk, crop insurance and replant options. It’s important to make wise decisions with the factors we can control during planting season as planting sets the stage for the rest of the year. So, some considerations:
1-Make sure your soil conditions are fit for planting. This can include the soil not being too wet to create sidewall compaction and getting the seed vee closed. I think the greater thing some will deal with is making sure there’s moisture where the seed is placed.
2-Along with the soil being fit is ensuring we’re getting the proper planting depth. With some moisture this winter, it appears we got more freeze/thaw action than last winter and the soil is more mellow. But that may not be true for all areas/fields. I recommend putting corn and soybeans in the ground at 2”. That may seem deep for beans but our UNL research found 1.75” seeding depth provided the highest yield for soybean. Proper seeding depth for corn is important for nodal root establishment. Proper seeding depth for soybean helps keep that seed in buffered soil moisture and temperature when planted early. It also aids that seedling from emerging too early. And, when planting, no matter what monitors say for seeding depth, I still recommend getting out and digging to make sure.
3-Another consideration is soil temp. Agronomically we’ve come a long way with genetics and seed treatments. Because of this, some don’t worry about soil temps. Yet every year I think most agronomists would say we can trace various problems back to a specific planting date(s) or planting window. So, I still feel they’re an important consideration.
I prefer removing one more stress off corn by putting it in the ground when soil temps will stay over 50F for 5-7 days, but realize that’s not always doable. And while we do share that early planting dates are the best way to increase soybean yield beyond genetics, our UNL and on-farm research for early vs. late planted soybeans was conducted with April planting dates of April 22 and later.
The consideration is for soil temps in the mid-40’s on a warming trend with no chance of a cold snap (cold rain/snow) within 8-24 hours for soybean and 48 hours for corn. The time-frame is due to the imbibition (critical water uptake) time-frame for corn and soybean. Soybean seed uptakes water more rapidly than corn and once the imbibition phase is complete, the soybean going through the osmotic phase can tolerate 35-40F soil temps as long as soil is not saturated. Soil temps for your field can be monitored by using a thermometer or checking out CropWatch soil temps at: https://cropwatch.unl.edu/soiltemperature.
4-For corn seeding rates, it’s best to check with your local seed dealer as all our research shows that optimal corn population varies by hybrid. However for soybean, our recommendation after 16 years of on-farm research studies (2006-2022) in heavier textured soils and 30″ rows continues to be: plant 120,000 seeds/acre, aim for a final plant stand of 100,000 plants/acre and you’ll save money without reducing yields. If that’s too scary, try reducing your rate to 140,000 seeds/acre or try testing it for yourself via on-farm research!
One final thought, make sure you’re keeping yourself and those in your operation safe by wearing proper PPE when handling treated seed. Seed tag labels will list PPE required for the seed treatments in case you weren’t aware of this. Here’s wishing you all the best whenever the planting season begins for your farm!
Hope you had a Blessed Easter!
Thoughts for 2023 Season
A week ago I was out east visiting family. Sunshiny daffodils were blooming in medians and we saw cherry blossoms and magnolias blooming at the National Arboretum in D.C. As I look in my backyard today, green leaves of tulips and daffodils are poking through. Rye, wheat, and lawns are greening up-the green this time of year is so stark in contrast to the brown. I’m so grateful to live in a place with seasons to see creation on display throughout the year!
March flew by and April is here. Another growing season will soon be upon us. I wasn’t mentally ready for another growing season. I’ve thought a lot about this and have heard this from others as well.
I knew I needed time in March to get my mind back into facing another one. I think of so many of you and there’s not been much break. Every spare moment of a ‘decent’ weather day this winter has been spent repairing/replacing pivots, buildings, bins, homes, or dealing with livestock.
I encourage us all to take some time to reflect on the blessings we’ve been given to work in agriculture, to be stewards of this land, and provide food for our families and the world. Reflecting on my purpose, “my why” for my Extension career and how blessed I am to get to serve many in this role, has reinvigorated my excitement for a new year. Perhaps reflect on “your why”? We have, we are, and will continue to face challenges as we aren’t in control of so much, especially the weather. But producers and those in ag careers are some of the most optimistic and resilient people I know. My hope is that we can all find some renewed joy and excitement for a new growing season!
Cover Crop Termination: For those who did plant small grains, the question of termination timing always comes up. The following are some thoughts to consider for planning. The temperature and year will determine how quickly a small grain will die.
- Termination timing considerations: https://jenreesources.com/2021/03/28/jenrees-3-28-21/.
- Photo gallery: https://jenreesources.com/2022/04/03/cover-crop-termination-including-planting-green/
- Can use only 20-22 oz/ac of Roundup Powermax (even when headed). Vetch + small grain: vetch will survive the Roundup application allowing it to produce more nitrogen. Can kill with post-app containing a Group 27 herbicide (like Callisto) later.
- Clethodim vs. glyphosate: clethodim provides a slower kill allowing the rye/wheat to stay greener longer for weed/erosion control. Benefit for farmers who need to terminate prior to corn or seed corn planting. Clethodim rates: most use 10-12 oz/ac. For corn, clethodim needs to be applied to the small grain to kill it at least 7 days prior to planting corn. For soybeans, can apply anytime after planting/emergence.
- When the small grain is greater than 12”, increase gallonage to 15-20 gal/ac for better coverage.
- When planting corn green into a small grain on subsurface drip irrigation (SDI), need the ability for higher capacity well to get moisture up to the seedbed. Potential yield loss otherwise.
- When planting soybeans green, the goal is often to off-set the PRE herbicide cost with the cover crop seed and application cost. A residual is necessary at some point either at time of termination or up to a week after termination when planting soybean green. Plan on 0.5-0.75″ irrigation/rainfall to get residual to the ground, especially on small grains taller than 12”.
- For those rolling small grains, roll twice if needed. And, plan on using a variety instead of VNS in future to help with evenness of maturity.
My key points for planting green include: plan on some form of nitrogen at planting if planting corn green into a small grain, have the pivot ready to go if need moisture for the seedbed, don’t use a PRE in soybean if can’t get seed vee closed, plan to water residual application as soon as label allows to get residual to ground, and if non-irrigated, consider seedbed moisture for termination timing. Have a Plan A, B, C.
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