Einstein’s Theory of Relativity as it Applies to Soil Moisture

Source: Dr. Bob Nielsen, Purdue University (Edited)

 

 

While Dr. Nielsen wrote this for Indiana, it unfortunately fits Ohio this year also.

 

Suitability of the soil moisture and whether a field is “fit” for field work and planting is partially “in the eyes of the beholder”, but is also subject to the “laws of relativity” and calendar date. Use your best judgement.

The bad news is that Monday’s USDA-NASS crop progress report estimated that only 6% of Indiana’s corn (4% of Ohio’s Corn) had been planted as of May 12, which puts our farmers in the unenviable position of suffering through the slowest planting progress EVER for this point in May. Nationally, only 30% of the corn crop was estimated to be planted as of May 12, compared with the most recent 5-year average progress of 66%. With more rain moving through the state late this week, let me offer a contrarian (if not “tongue in cheek”) view about soil moisture and planting.

The superintendent of our Purdue Agronomy Farm and I commiserate every planting season when it comes to deciding when the soil is “fit” to work or plant. We scuff the surface of the fields in mid-April, dig a few spadefuls of soil, squeeze the soil into a ball like the soil scientists tell us to do, and then agree that the soil is too wet to work or plant.

Around the first of May, we scuff the surface of the fields, dig a few spadefuls of soil, squeeze the soil into a ball like the soil scientists tell us to do, and then agree that the soil is too wet to work or plant.

Again in mid-May, we scuff the surface of the fields, dig a few spadefuls of soil, squeeze the soil into a ball like the soil scientists tell us to do, and then agree that the soil is maybe just about right to work or plant, but we’ll give it a few more days.

By late May, we scuff the surface of the fields, dig a few spadefuls of soil, squeeze the soil into a ball like the soil scientists tell us to do, and then agree that the soil is just as wet as it was back in mid-April, but maybe we ought to be working ground and planting anyway.

Einstein was right…………it’s all about relativity.

The point of my sharing this annual ritual with you is that we are rapidly approaching the point in the planting season where we need to “fish or cut bait”. Yes, there are risks of working ground too wet or planting “on the wet side” (see articles below), but there are also risks of waiting so long for the soil to become “fit” to begin planting that the majority of your corn ground gets planted way too late.

Heaven forbid that I should recommend anyone to work ground or plant corn in soils that are wet enough to cause severe compaction that will haunt you later this summer. But, you know, when you decide back in mid-April to wait, you’ve got quite a bit of good planting season left to go. When you decide in mid-May to wait AND you have a lot of acres to cover, what you save by avoiding some soil compaction now may be less than what you risk by planting the bulk of your corn acres very, very late.

If you concur with these thoughts and decide to “mud in” your corn and suffer serious yield losses; then you did not hear it from me. If you “pull the trigger” now and successfully avoid planting the bulk of your corn in mid-June and win the yield jackpot; then I’ll accept all the credit.

There are no black & white answers to this situation, there are no silver bullets, and there are no certainties in farming. Use your best judgement in deciding when to head back to the fields over the coming days and/or weeks. You know your fields and soils better than anyone else.

Delayed Planting Effects on Corn Yield: A “Historical” Perspective

According to the USDA/NASS, for the week ending May 5, only 2% of Ohio’s projected corn acreage was planted – compared to 20% last year and 27% for the five-year average. Persistent rains and saturated soil conditions have delayed corn planting. The weather forecast this week indicates the likelihood of more rain, so it is probable that many soggy fields may not dry out soon.

Long-term research by universities and seed companies across the Corn Belt gives us a pretty good idea of planting date effects on relative yield potential. The recommended time for planting corn in northern Ohio is April 15 to May 10 and in southern Ohio, April 10 to May 10. In the central Corn Belt, estimated yield loss per day with delayed planting varies from about 0.3% per day early in May to about 1% per day by the end of May (Nielsen, 2019). These yield losses can be attributed to a number of factors including a shorter growing season, greater disease and insect pressure and higher risk of hot, dry conditions during pollination.

Continue reading

Corn Management Practices for Later Planting Dates – Changes to Consider

Source: Peter Thomison, Steve Culman

As prospects for a timely start to spring planting diminish, growers need to reassess their planting strategies and consider adjustments. Since delayed planting reduces the yield potential of corn, the foremost attention should be given to management practices that will expedite crop establishment. The following are some suggestions and guidelines to consider in dealing with a late planting season.

Although the penalty for late planting is important, care should be taken to avoid tillage and planting operations when soil is wet. Yield reductions resulting from “mudding the seed in” are usually much greater than those resulting from a slight planting delay. Yields may be reduced somewhat this year due to delayed planting,  but effects of soil compaction can reduce yield for several years to come. Keep in mind that we typically do not see significant yield reductions due to late planting until mid-May or even later in some years. In 2017, favorable growing conditions allowed many growers to achieve exceptionally grain high yields in corn planted as late as early June.

If you originally planned to apply nitrogen pre-plant, consider alternatives so that planting is not further delayed when favorable planting conditions occur. Although application of anhydrous N is usually recommended prior to April 15 in order to minimize potential injury to emerging corn, anhydrous N may be applied as close as a week before planting (unless hot, dry weather is predicted). In late planting seasons associated with wet cool soil conditions, growers should consider side-dressing anhydrous N (or UAN liquid solutions) and applying a minimum of 30 lb/N broadcast or banded to stimulate early seedling growth. These approaches will allow greater time for planting. Continue reading

Yield Response of Corn to Plant Population in Indiana

Source: RL (Bob) Nielsen, Jim Camberato, & Jason Lee Purdue University (Edited)

Summary:

Results from 97 field scale trials around Indiana since 2008 suggest that maximum yield response to plant populations for 30-inch row corn grown under minimal to moderate stress conditions occurs at about 32,150 plants per acre (ppa), equal to seeding rates of about 33,840 SEEDS per acre (spa). Economic optimum populations are several thousand lower than the agronomic optimum. Corn grown under extremely challenging conditions (e.g., severe drought stress) may perform best at plant populations no higher than 22,800 ppa and perhaps as low as 21,000 ppa under truly severe growing conditions (e.g., actual drought, non-irrigated center pivot corners, non-irrigated sandy fields with minimal rainfall).

The cost of seed corn is the largest single variable input cost for most Indiana corn growers(Dobbins et al., 2019). Minimizing that cost involves a combination of shrewd purchasing skills and wise selection of seeding rates. This summary focuses on our recent research evaluating the yield responses of corn to plant populations in field scale trials conducted around the state of Indiana since 2008.

Reported corn plant populations have increased steadily in Indiana (and Ohio) for the past several decades, at an annual increase of approximately 315 plants per acre (ppa) per year, based on historical data summarized by the USDA National Agricultural Statistics Service. In 2018, the average reported plant population for Indiana (and Ohio) was approximately 30,400 PLANTS per acre (USDA-NASS, 2019). Considering stand establishment success typically ranges from 90% to 95%, the average reported population suggests that the average seeding rate statewide is 32,000 to 33,800 seeds per acre (spa). Among the agronomic factors that support the steady annual increase in plant populations has been the genetic improvement in overall stress tolerance that has resulted in a) ear size and kernel weight becoming less sensitive to the stress of thicker stands of corn and b) improved late-season stalk health.

Click here to read the entire study

 

SPRING ROLLER COASTER RIDE COMING

Source:  Jim Noel (Edited)

It is spring and with it often comes wild swings. This is what we expect for the rest of April 2019.

A parade of storms will begin later this Thursday (4/11) into Friday (4/12) and follow every 3-5 days. This will cause 2-3 inches of rain on average for Ohio the next two weeks as shown in the attached graphic. Normal rainfall is now almost 1 inch per week. Hence, slightly above normal rainfall is expected. The one exception could be northern and northwest Ohio where it is possible to see less rainfall depending on the exact storm tracks.

We are also fast approaching our end of the freeze season typically in mid April up to around the 20th for much of the state. Some places in the north it can be late April. Right now, everything looks like a normal end to the freeze season. We do see the possibility of another freeze this weekend on Sunday AM especially north of I-70. A few more could happen into the next week or two before coming to an end.

Temperatures are expected to overall be slightly above normal for the rest the rest of April but with wild swings. This should help bring 2-4 inch soil temperatures into the normal range, possibly a degree or so above normal. The exception would be northern Ohio where above normal ice levels this past winter on the Great Lakes will keep water temperatures on the Lakes lagging and may keep air temperatures closer to normal there.

With all the storms lined up, we do expect a windy April as well. Winds of 30-40 mph with gust to 50 mph can not be ruled out Thursday (4/11) or Friday (4/12) this week with storm number one. 30-40 mph winds will also be possible with the storm later Sunday into next Monday and can not be ruled out with the third storm later next week.

After a wetter April indications are for a warmer and not as wet May with the possibility of normal or even a bit below normal rainfall.

Early indications for the summer growing season are normal or slightly above normal temperatures and possibly a bit wetter than normal though June could be a bit drier.

Soybean Planting – Does maturity group affect planting date?

Source: University of Illinois

Should later-maturing varieties be planted first in order to take maximum advantage of the longer time in the field? There’s no problem with doing that, although early planting moves up harvest date some, so works counter to the goal of spreading harvest time by using different maturities. In 2018 we ran a trial at Urbana, supported by a seed company, to see how varietal maturity affected response to planting date. The first planting date was April 26, the last was June 6, and varieties ranged in maturity from MG 2.3 (very early for this location) to MG 3.6, which is a little later than average for this location.

 

For all but the earliest-maturing variety in this trial, the planting date response was almost perfectly linear, with the loss of nearly 7/10ths of a bushel per day of planting delay—a total of more than 27 bushels—over the 41 days from the first to the last date (Figure 2). This loss rate accelerated a little for the latest-maturing variety between May 24 and June 6. The earliest-maturing variety lost only 17 bushels from first to last planting, but only because its yield at the earliest date was so much lower than yields of the later-maturing varieties.

The month of May 2018 was much warmer than normal, and this got the soybean plants off to a very fast start. Warm nights are conducive to early flowering, and this was especially notable in 2018. In the early-planted crop, first flowers appeared in early June, well before the longest day of the year, and unlike the interruption of flowering that often takes place under normal night temperatures for about a week before and after the longest day, flowering was early and continuous in 2018. As a result, nearly half of the Illinois soybean crop was flowering by July 1. The warm May probably affected the yield response to planting date as well; with warm temperatures, early-planted soybeans as fast as late-planted ones, and this widened the developmental gap between the different plantings.

Planted on April 26, the earliest variety reached first flower on June 9 and matured on August 28, compared to June 15 and September 17 for the latest-maturing variety. When planted on May 24, the earlier and later varieties flowered on June 15 and July 2, and matured on September 12 and September 25, respectively. So when planted late, both varieties flowered very early in their life cycles, both spent less time in reproductive stages than when they were planted early, and they ended up yielding about the same. While in this case it’s accurate to say that the later-maturing variety benefitted more from early planting, that’s only because the early-maturing one was physiologically less able to use the longer growing period allowed by early planting to produce high yield.

Knox County Soybean Seeding Rate – Trial #1

A BIG thank you to Jim & Susan Braddock for allowing me to put two of my Soybean Seeding Rate trials on their farm this year!

 

 

The results are listed in the tables below.

The 2018 report is now available in both a print and e-version. To receive a printed copy, stop by the Knox County Extension office.  The e-version can be viewed and downloaded here at go.osu.edu/eFields.

Knox County Soybean Seeding Rate – Trial #2

A BIG thank you to Jim & Susan Braddock for allowing me to put two of my Soybean Seeding Rate trials on their farm this year!

 

The results are shown in the tables below.

The 2018 report is now available in both a print and e-version. To receive a printed copy, stop by the Knox County Extension office.  The e-version can be viewed and downloaded here at go.osu.edu/eFields.

Variable Rate Corn Seeding Considerations

Source: Alexander Lindsey, Peter Thomison, Emerson Nafziger

As producers are planning their seed needs for next year, it is important to think about acreage, hybrids, and seeding rates. Finding the best corn seeding rate is important for efficient production, but the “optimum” corn seeding rate – the one that maximizes profitability – can vary within and among fields with small differences in soils and weather. While adoption of variable rate technology is increasing, there are still questions related to how this technology will impact seeding rates, profitability, and be impacted by yield level compared to using a uniform (or fixed) seeding rate with modern hybrids. In order to help estimate the profitability of variable rate corn seeding in the US Corn Belt, we used results of 93 seeding rate trials in Ohio (2012-2016) to see how variable the response to seeding rates was, and to see if factors like yield level might help us do a better job of setting plant populations.

Continue reading

Knox County Crop Conditions

Perfect time to grow corn

by: Chuck Martin, Mount Vernon News

 

The right weather at the right time, along with the right management by farmers, and the crops will respond.

That, essentially, is what has happened with the corn crop so far this year, said Knox County Ohio State University Extension Educator John Barker.

“There was a time, early, when there was a little concern about planting because it was so wet,” he said, “but most of the fields got planted and with the combination of heat and moisture, the corn just took off.”

Some fields were even tasseling out by July 4.

“That’s what we want to see,” said Barker. “The old adage of corn needing to be “knee high by the Fourth of July” is from a time when corn was often not planted as early.

“At one time many farmers didn’t think about planting until May 1, now they expect to be done by May 1.”

Click to read more …