Crop Watch
October 7, 2016
By Bob Streit – Columnist, Farm News
October brings its shorter days, cooler temps and a harvest that is well underway. In the state the big news last week and the week before were the big rains that fell in eastern Iowa, southern Minnesota and many points to the east.
This was at a time when moisture removal by plants is no longer a factor, thus drying of the ground is much more dependent on field tiles and ditches.
Soil health
In a related issue the Leopold Center newsletter arrived and director Mark Rasmussen wrote an interesting article how some of the National Parks – the Badlands in South Dakota, the Grand Canyon in Arizona, and Zion and Canyon Lands in Utah – were formed by soil erosion. He said that people love to look at natural disaster and the results.
While the erosive scenery and immenseness can be spectacular it can also cause the downfall of civilizations and countries when they do not value and take care of their productive top soils. We listened to Dr. Jerry Hatfield about a month ago where he stated and showed the figures for the amount of topsoil that is still eroding off many acres within the Midwest.
Jerry’s team members at the Soils Lab are continuing to work with cover crops and different forms of tillage to provide ammunition to growers who want to be proactive in preserving the ground they or their forebearers spent their lives acquiring and working.
In the Leopold Letter there were details about a program where small strips of grass and erosion controlling perennials that were slowing down the running water and served to catch dislodged soils.
At the same time many of those perennials served as cover or food for wildlife or pollinators. It is just unfortunate that some of the seed in 2016 was contaminated with Palmer amaranth, which originated from a southern source and was less expensive.
Fertilizing
A recent article coming from the Extension folks in Minnesota covered a topic that could end up being quite important. There is much more news in the last year about soil health, how it can be defined, how it functions, and how to measure it.
They penned a piece dealing with how we should be using soil health measurements, namely Haney soil quality scores, and if those results could and should interact with fertility recommendations.
Long-time students, practitioners and growers who have had soil biology in mind over the past 1 to 2 decades knew that raising oxygen levels allowed richer biological activity lending efficient conversion of pounds of nutrients into bushels of grain or tons of forage.
Check for the article on our webpage at CentralIowaAg.com.
Researchers like Jill Clapperton and Bob Kremer have been on life-long quests to develop more of the answers and paths that current and future leaders and researchers can follow.
Our thinking about soil fertility has evolved to recognize that there is a big biological component to soil fertility and is no longer completely dependent on chemical equations.
Yield contest winners tell how they work to build soil biology in their soils. Farmers in Brazil are conscientious to do the same in their highly weathered soils for the same reason.
Yield reports
Farmers have had to switch between harvesting corn and beans depending on soil conditions and the amount of heavy dews and fogs. The definite trend is that corn yields in most Midwest states are below USDA expectations except in Minnesota, while soybeans are above what farmers were expecting.
The exception on corn is where proactive nutrition was used to boost late-season plant health.
While riding in a combine on Sunday, the fields were yielding 240 with spots hitting 270 to 290 on the monitor. What made this surprising was that on very loose, fluffy and 13.6 Haney-scored soil suffered from soil compaction caused by his planting rig and was severe with traffic-affected rows appearing very yellow and stunted through the tasselling stage.
Thus the 240 average was surprisingly good. The fields had received a brewed biology mix at planting, micronutrients, BE and a foliar fungicide. It had stayed green until Sept 20 and each ear was filled to the tip. His other fields should be better.
The common theme among growers and insurance adjustors is that most corn yields are 15 to 20 bushels per acre under last year unless there were proactive steps taken to improve plant health and keep the leaves green and healthy into mid- to late-September. This appears to be nationwide again.
The corn crop stayed alive about two weeks longer than in 2015 and three weeks longer than in 2014. It received its death blow on Sept. 7 with the 90-plus -degree temps and 25 mph winds. Before that time NDVI imagery showed less green in the countryside beginning about mid July. Driving back from Chicago on July 10, a person could see a barely perceptible change in the corn color to a more yellowish tint. That was in areas that had not had excess moisture.
Bean yields have been excellent and in most cases exceeded expectations on both light and heavy soils. The plants grew very tall this year and a common complaint is that standability became an issue as they get matted down.
An application or two of foliar chelated calcium would have been a good recommendation to follow to boost standability. I was riding with a central Iowa grower at the start of the Viking’s game Monday night and his whole farm average was running over 76 bpa, his best ever by quite a few bushels. Seed-applied products, new and proven inoculants, foliar nutrition and good disease control paid off in his proactive program.
Now the challenge will be figuring out what yield goal to set for his fields in 2017.
New diseases
The newer tar shot fungal disease seen in Illinois in 2015 was diagnosed in eastern Iowa recently. It is caused by Phyllachora maydis and it appears in warm, wet weather. Another leaf disease that has increased in incidence and severity in recent weeks has been Southern Rust.
Its symptoms are lots of small, raised, reddish dots on the upper surface of the leaves. Heavy pressure from this disease has been known to kill corn plants in rapid fashion. Folicur is still a very good and affordable product to control rusts, with the problem being that most brown silk timed applications have worn off after two to three weeks.
In past weeks I have mentioned healthy, still green corn growing near Guthrie Center. As of Oct 3 many of those fields still hold plants that are 70 percent green. The kernels are about .75-inch deep and until recently were still filling.
USDA yield guesses
Why did the government agencies do everything in their power to project record 2016 crop yields? Is that a valid question and why does it happen?
In a recent article by the National Yield Forecast Center connected with the University of Nebraska, the facts were given that their estimates don’t take into account factors such as plant stands, hail and flooding, replant situations, disease and nitrogen factors.
That might be realistic in LaLa Land, but in the real world all of those factors affect yield and are what growers are forced to manage.
Future forecasting when it affects cash flows and farm financials needs to be improved. You can bet major grain traders had their NDVI info to base their actions upon.
You may want to bring this up at winter meetings and demand good answers and action. Again check our website to read this article.
Be safe in your harvest activity. Your family needs you.
Bob Streit is an independent crop consultant and columnist for Farm News. He can be reached at (515) 709-0143 or www.CentralIowaAg.com.