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By Staff | Aug 30, 2013

We are nearing the end of the last full month of summer, so now it is on to late summer and early fall weather and activities.

That may sound like good logic, except that we are left hoping for several good rains and a super long growing season so all late-planted corn and beans can make it to maturity before a freeze brings a halt to the growing season.

Over much of the state most growers can’t wait for the calendar to turn over and the next cropping season to be on their minds.

Anything to forget the 2013 growing season is what they want.

So who turned on the heat? In a year where we waited for the snow to melt, for conditions to warm up and the soils to dry, this burst of heat is going to be what was needed for the few who have adequate soil moisture reserves, and a big negative for those who crops are moisture stressed or are being pushed too fast through grain fill.

It is reminiscent of the first weekend in August 1983 when hot and windy conditions killed entire corn fields during one weekend, causing decent yields to disappear.

Guesses are that yields are going to be affected, and there is risk that it could cause yield losses above 10 percent in many fields and states.

We’ll know more at the end of the current warm spell which is predicted by several meteorologists to last until Sept 4.

Our friendly USDA

A few articles ago I was stating what has become a common farmer response to the USDA announcing the prevented planting acreage total as 200,000 acres, which was what officials were underestimating for Iowa.

Ayone who tours some of the heaviest hit counties or talks to growers in areas most affected could read the tea leaves and recognize what was an official false flag. The accurate tally appears to be that the actual acre amount was 370 percent higher than the initial announced total. If the goal was to let end-users buy grain at lower prices, that objective was met.

If it was meant to lower potential insurance payout, that may be achieved. The market has reacted to potential shortfalls and has corrected already.

It could be a very wild ride over the next few weeks as grain traders will have to wait for the first harvest results to verify who was right.


Last week I used the term 40-40-40. A number of people ask me what that meant. It was a term used during a few harvests in the 1980s when we had a few late-planting seasons and early frosts that arrived before the plants had matured. The plants had developed at a slow rate, and the entire maturity process was behind schedule. Then it froze early before the black layer had formed and before the husks opened.

As a result there were many growers in northern Iowa that ended up harvesting corn that yielded about 40 bushels per acre, carried 40 percent moisture and a 40-pound per bushel test weight. Though it seems like a tall tale there were growers who took such wet grain to the elevator and after figuring out the drying charge and light test weight dock ended up with a negative balance and would have been charged to leave their grain there.

What’s dramatically different in today’s situation is that hybrids have much lighter husk covers that open earlier and should dry faster. The earlier hybrids also move south better and have higher yield potentials.

However with corn planting delayed into mid-June in parts of Iowa and the lack of growing degree units during July and early August one can’t bet against some of the later-planted fields and their grain having similar problems if the cold conditions arrive before or at their normal date.

Declining corn crop

Small airplane pilots say the corn crop is getting ugly from their viewpoint. The view from the road is telling a similar story depending on region, fertility practices, herbicides used, level of plant nutrition, rooting depth, amount of compaction, level of root feeding, loss of nitrogen, variety and genetic family involved and disease tolerance.

A few areas within the region, like Iowa Falls and Hampton north and east, Waterloo through Dubuque, Sioux City and eastern Nebraska have received good moisture in August and their corn crop looks better.

There are issues besides moisture that are determining plant survival. It is often easy to see fields that are still dark green and tolerating the dry conditions without showing any stress. There has to be a correlation to level of Goss’s wilt infection as the bacteria does much of its damage by plugging the plants plumbing tissue, hindering its ability to pull in moisture and nutrients, along with the ability to cool itself through the evaporation transpiration process.

This week’s 90-plus degree weather is the last thing any plant doctors recommended. We lucked out earlier with the 75-degree weather, but no more.

With a warm wind, daily evapotranspiration, with an ear in the milk or dough stage, has to be in the .25 to .3 per day range. But there is little moisture available.

This is the time when a deeper and porous subsoil along with good moisture infiltration that can soak up spring rains help keep the plants going.

If the heat wave lasts as long as several meteorologist predict, it will have an effect on kernel depth, amount of tip back and eventually late-season standability.

Anything that subtracts from the ability to form sugars will weaken the stalk. If growers responded to early season micronutrients deficiency symptoms it is easy to see those plants tolerating dry conditions better.

Row crop insects

I have been waiting for the spider mites to show up and begin multiplying on the underside of the leaves. This is now happening in the western one-third of the state. I have seen some fields where the bottom half of the plants are webbed now.

A few of the same critters are trying to explode on soybeans as well with some level of success. I don’t foresee many farmers spraying due to their expectations on yields.

It is also possible to find corn aphids now. One can also see the shiny leaves where the honey dew is being deposited where the aphids fed.

One question about them is can they do any damage to the plants or the yields? The answer is the same as a few years ago – little documented research has been done with them at any university.

The effects seem to be variety specific. Their feeding removes saps that should be used to fill the kernels and not the insects’ bellies.

Two to three years ago late-spraying of heavily infested fields by farmers in northwest and western Iowa showed a 20 to 30 bpa advantage to treatment being made.

Stripping of a volatile insecticide can be effective while minimizing application, labor and product cost.

Soybean yield prospects

Overall the soybean plants in many on-time and late-planted fields don’t seem to have what is needed for top yields. Podded nodes, branch number and pod numbers are all down, especially for those who did not manage to maximize each of those characteristics.

Those that have been treated very well have better yield potential, but will still need moisture to retain and fill those small pods.


I was visiting with an astute grower who remarked that farmers may be better off growing a perennial, deep-rooted crop that does not have to start over each year. That makes sense, but what crop falls into that category?

I got the chance to scout an alfalfa field near Carroll that is now ready to be mowed for the fourth time this season. It was sprayed with a liquid mineral and glucoheptonane mix along with a micronized mineral product a few days after the third crop was baled.

Even without any rain in the previous 10 weeks this cutting is knee high, dark green, healthy and shows no signs of any problems.

Cover crops

If you have not planted your cover crops yet it is time to do so shortly. Any of them will need a rain to get started.

Once they begin growing they will help reduce erosion and help moisture infiltration plus help keep soil biology alive.

Bob Streit is an independent crop consultant and columnist for Farm News. He can be reached at (515) 709-0143.

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