by Jennny Rees, UNL Extension
Harvest is rapidly progressing with some pleased with yields and others not so much. The past week, I've answered a number of calls and looked at samples of ear rot in addition to a few corn plant carcasses. It's hard to determine causes for lower yields from samples provided this time of year. This year was another challenging one regarding the environmental conditions and various biological factors that also affected our crops. The following are some factors for consideration on a field by field basis. The full article with photos and weather graphs can be viewed at http://cropwatch.unl.edu.
As we review planting and early season conditions, variability in precipitation with excess moisture in some locations led to variable planting dates with some replanting. It also led to variable emergence and plant growth within fields. Damping off and other seedling diseases were a problem in some fields and in some hybrids, resulting in stand losses.
Excess moisture may have resulted in denitrification or leaching of nitrogen in some fields where nitrogen was applied pre-plant. If rescue treatments or the majority of nitrogen could not be applied in-season, nitrogen stress may have occurred. Excess moisture also affected some post-herbicide applications which may have resulted in weed pressure in some fields, potentially impacting yield.
As June rolled around, growers may recall plants appearing yellow from lack of root development from April and May rainfall. We also had high heat and high winds in June which made the soil hard and increased plant stress from lack of root development. Some corn plants were in a critical growth stage (V5-V8) during this time. Irrigation was recommended to help reduce plant stress.
Rapid plant growth continued to occur. A cold snap over the July 4 weekend followed by a July 7 windstorm with hail affected pockets throughout the state. Plants most affected by greensnap were between V10 and V14 growth stage at this time. By the end of July there was a period of high nighttime temperatures which may have affected kernel setting. By late summer, portions of the state were in drought because of limited rainfall from early June through August. Solar radiation was good for both corn and soybean yields; however, the high relative humidity resulted in reduced evapotranspiration (ET). The high humidity did appear to help plants in drought-stricken areas hang on longer. Ear formation concerns were also observed on racehorse hybrids and determined to be the loss of the primary ear node although exact reasons for this are still being determined. Insects such as western bean cutworms and grasshoppers were an issue throughout the state. Spider mite flare-ups occurred during milk to early dent growth stages with some farmers questioning additional pesticide applications given current economics.
Bacterial leaf streak was observed in plants as early as V7 and appeared in a more wide-spread area after the July 7 wind storm. Gray leaf spot was often confused with bacterial leaf streak, eventually with both occurring on the same plants as the season progressed. Southern rust showed up with some growers surprised at the rapid increase late season that may have impacted yield and standability.
September resulted in corn appearing to rapidly lose health and we didn't see the long period of drying husks on green stalks as is often observed. Weather data shows a period with low solar radiation during this time, which may have impacted corn plants physiologically. Several stalk rot diseases can cause early plant death and potentially impact yield if they infect and develop early. These diseases are caused by fungi that survive in the soil and infect and develop in plants that may have been grown under crop stress, such as nutrient deficiency, moisture imbalance (too wet or too dry), wounding, and loss of leaf area, such as caused by leaf diseases, among others. Hybrid selection may help to reduce the incidence of stalk rot diseases. Anthracnose stalk rot (and top dieback), as well as Fusarium stalk rot have been observed, and others, such as charcoal rot, which is more common in dry growing conditions, also could be possible.
Ear rot diseases have been observed somewhat in the past few weeks. Tamra Jackson-Ziems and I wrote another article regarding in this week's CropWatch at http://cropwatch.unl.edu with photos and detailed information on what to look for. Everything I've seen thus far has been Fusarium Gibberella, Diplodia or Penicillium. Some have complained about ear shanks being fragile with ears dropping easily and what some are calling "cob rot." Most of what I'm seeing is limited to where insect damage, ear formation or tight husks occurred. It's important to scout high risk fields and to know whether they're a problem to help make informed decisions about storage and feeding.
Not affecting yield, but something I'm also hearing reports about is "black dust" on combines and augers during harvest. This is most likely because of secondary fungi feeding on dead or decaying plant tissue and these fungi release copious amounts of spores. More information on this can also be seen at at http://cropwatch.unl.edu.
In summary, a number of factors across this production season may be affecting yields. If you are experiencing lower than expected yields, consider the factors listed in this article to help determine what might have affected your crop on a field-by-field basis.
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When in Rome,
don't do like the politicians
By Greg Allen
Some say the United States is no longer a superpower - such a distinction can only be defined by history, one's perception, or a theoretical comparison thereof.
There's an old adage that says: "When in Rome, do what the Romans do." Well, there's a widely held belief Rome fell in 476 A.D. Some say since Rome still exists it never really fell. A few prefer to say Rome adapted rather than fell - that's no doubt a politically correct pry.
The Roman Empire was a superpower at the time and failed, yet many in society today are staunch to say: "The United States is too big to fail."
I beg to differ; there are many similarities linking the fall of Rome to the path the United States is upon.
Historians of ancient Rome have long been fascinated with the fall of that powerful empire.
Rome started out as a small settlement by the Tiber River in the heart of Italy.
America started out as a small uprising against tyranny.
The Roman Empire reached its greatest extent in the second century, but Rome had become too big to easily control.
For a long time, the Roman Empire functioned well and was successful. It amassed power and wealth and survived for centuries. However, the Empire was more than the top echelon and like a bone with osteoporosis that still looks alive it was disintegrating from within.
The Fall of Rome lay mainly in financial difficulties. For those looking for a single cause, the best single explanation would be poor leadership rather than military failure. Causes of the Fall of Rome included economic decay, a lack of circulating currency from hoarding and looting of the treasury, inflation, trade deficits, environmental change, decaying infrastructure, poor management, and military decay through attrition and disorganization from the lack of an effective military leader.
The decline of Rome was the natural and inevitable effect of immoderate greatness. Prosperity ripened the principle of decay.
The other side of Roman decadence was the dole. Millions were spent on food and public spectacles, called circuses, for the non-working poor.
There are adherents to single factors, but many think a combination of decadence, imperial incompetence, monetary trouble, military problems, the rise of Christianity, and rampant corruption caused the Fall of Rome.
Does any of the shortcomings of the Roman Empire, which it inflicted upon itself, sound familiar to that which politicians have vexed our nation with?
Since 1937, 629 municipalities have filed for bankruptcy protection in America.
Since 2010, Jefferson County, Ala., Harrisburg, Pa., Central Falls, R.I., Boise County, Ida., San Bernardino, Calif., Mammoth Lakes, Calif., Stockton, Calif., and Detroit, Mich., have filed for Chapter 9 bankruptcy protection.
Other US cities on the verge of bankruptcy are Washington D.C., Honolulu, New York City, Chicago, Cincinnati, Camden, San Diego, San Jose, San Francisco and Los Angeles.
Citizenship granted to all in the Roman Empire reduced the incentive to join the army and gradual transformation took place - hence, a correlation to amnesty could no doubt be adhered.
Massive trade deficits served to stifle growth in Rome and the Empire was split geographically and culturally with a Latin Empire and a Greek one; division became the norm.
I daresay "Class Warfare" is at the pinnacle of the current administration's ambitions.
The extensive empire put such a strain on Roman coffers that Emperor Honorius sent letters to the Roman cities in England to tell them they'd have to fend for themselves.
The similarities that vexed the Roman Empire and now America are simply too great to ignore.
Dissension in the ranks of the Roman citizenry was met with swift retaliation and even death. Public floggings and crucifixions were commonplace and were often carried out on public byways as a deterrent for all to see. But these days most think we're a little more civilized than that, although our jails and prisons are overcrowded and murder is rampant in some American cities.
Although there's no public floggings it would appear the current administration has chosen to combat discord with the strong arm of government agency control.