×
×
homepage logo

CROP WATCH

By Staff | Jun 30, 2013

It is now late June and there are lots more questions than answers about how the rest of the season could turn out.

To this point 75 percent of Iowa growers would love to start completely over from about March 15. Several meteorologists warned us that if there was any way to fill a large portion of the moisture profile up that occurrence could be accompanied by the risk of having the planting season delayed.

In the end that stated risk was an understatement.

The National Agricultural Statistics Service released its weekly figures about how great the crops were in each of the major states.

And just like last week, growers who had observed their own crops or those in their respective states of neighborhood wondered how they could be so off-base.

If the conditions of the corn and bean crops were so good, then why are such a high percentage of those fields strong candidates for replanting or even for planting the first time?

Personally we had to head to Mitchell and Floyd counties last weekend for a baptism.

What we observed in those counties was that in large areas about half of the fields were still black, either having never been worked, rotting off in large sections, or being planted only two or three days earlier.

Any of those items are recipes for crop problems given the fact that the early frost date in that part of the state is only 75 to 80 days off. The risk is less as one moves south, but the threat of frost before the corn crop black layers does exist over the entire state.

Crop conditions

Currently, the best crops I have seen are on rolling ground in central, eastern and western Iowa. At the same time the worst are those that lay flat and are part of the pothole region.

Next are those rolling fields where the soils in their sidehill areas have remained saturated.

Conditions finally improved the middle part of last week, and growers who still had crops to plant and fields that were dry enough to work or plant were making progress. A lot of the original enthusiasm was gone as hopes for good yielding crops were dashed.

Just getting those final acres in, to be able to say they were done, deciding to fill in those waterholes with new seed or throwing in the towel and making the choice to take prevented planting is what lots of farmers did.

In a year where there is very little carryover grain and USDA policy should be set to encourage some production on every acre, it is actually doing the opposite. Is that by accident or design?

In reading the comments from one commodity advisor who farms he said that in most years growers who have a few problems with their fields would be inclined to spot-sidedress additional nitrogen in drowned areas if it was called for, and spray for bugs or weeds if it were needed.

This knowledgeable person believed that he and neighbors had fields that were so far below average condition that they could not spend any more money on them.

Is that right or wrong or just being realistic? For the first time I can remember when I wrote up my evaluation of one field after scouting it I just wrote “RIP” on the sheet.

Having 80 to 90 percent of the acres in field forces that conclusion.

Better fields

Many fields that still contain decent stands did seem to improve in size and appearance. Those that have not tend to be an uneven yellow with uneven growth.

A common cause of problems seems to center on having soils that are still saturated and the plant roots are not functioning as they should to pull in the nutrients contained in the root zone.

On the taller fields, the bigger corn plants began to use more moisture and worked to lower the water table and explore more soil for nutrients and micronutrients. There were many sidedress rigs working to apply an additional 40 to 60 pounds. Wherever such work was done it was good to study the leaves first to see if any yellowing was due to N shortage, or due to poor N use efficiency due to copper, manganese and zinc levels. Tissue sampling and analysis may be needed.

With fields that are still quite small, growers will have many questions about what to expect from them. They have to know that when corn is planted after May 25 to May 30, the plants will stay shorter than if planted in early- to mid-May.

The key with maturity and getting the fields safe from frost will hinge on when they tassel and begin silking. Most hybrids require 60 days from silk to black layer. Earlier maturity hybrids typically require fewer days to complete their vegetative growth.

Thus every corn grower who planted one or several fields late will have to sweat from the time their plants flower to hopefully a later-than-normal frost date.

While we hate to think about having days with temps above 84 degrees, hotter days through July and August will be vital.

Field symptoms

Over the last two weeks there were many corn fields that began to show lots of yellowing. A portion of that was loss of N, while in others it was nutrient deficiency or a combination of the two.

In a portion of those fields the growers were able to take their sprayers or sidedress applicators into those fields and make applications of the appropriate product(s).

In some of the fields the problem seemed to be more complex and a bit outside of immediate human control. What seemed to be going on was that with crusted, saturated soils the root systems were not taking up all of the minerals contained in the root zone.

Thus the nutrients were present but were functionally and positionally unavailable. In cases where this was happening, we saw benefits from a product called Foliar Blend or a mix of products that fed the microbe populations in the root zone.

In turn, these microbes began doing their jobs again, which was to move those minerals into the zone where the plants could pull those in.

This phenomenon is well proven and work has shown that up to half of the sugars formed through photosynthesis are moved out the roots to feed root dwelling microbes to support this commensual relationship.

Such field problems are still occurring and evident. And often growers wish to get into the fields to remediate the problem, but with the constant rains they are prevented from getting in with the sprayer.

This includes managing weed populations as well as applying fertilizers. At a certain point in time and plant height only those with high clearance rigs can get into a crop to make any applications.

Goss’ wilt in Louisiana

One recent announcement from a southern corn growing state is that they diagnosed Goss’ wilt for the first time in Louisiana. Field scouts and farmers noticed the symptoms and called in university officials to make the determination.

After looking at it they decided they had been misdiagnosing it and calling it something different.

What they did mention was that it was first noticed as round circular infestations common with seed transmission.

The officials stated that it appears that lack of control in the seed fields in 2012 was to blame for bringing the disease into the state. Their corn acres will be advanced in growth stage versus ours, but it may mean we should be scouting for it shortly.

Japanese beetles

A recent insect pest that has become noticeable due to its high numbers is the Japanese beetle.

These beetles can cause problems with corn and beans as well as about any other fruit, veggie or vine crop.

I saw my first one this week where it had drowned when it visited a small hand sprayer. This might signal the emergence of the pupating insects that originate from grass-eating grubs in the soil.

Here’s hoping you get enough dry weather to get all the work done.

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

Please Enter Your Facebook App ID. Required for FB Comments. Click here for FB Comments Settings page