CROP WATCH
September is now here and we all know what is coming next. It is a time for the crops to now finish the grain filling stage and mature. Hopefully farmers and their crops in the Midwest states will get enough heat in the next three or four weeks to make that all happen.
It would be a shame to have the most expensive crops we have ever grown not reach maturity. That would create many other problems that would lead to a poor start to the 2010 season.
Cool weather was the rule across Iowa last week, which we didn’t need. It was the same, plus lots of rain across eastern Iowa, which they didn’t need. Receiving 3 to 12 inches of rain just when many farmers were watching their soybeans begin to die from white mold, and or SDS, was not good. It was the same for corn growers who watched previously clean corn plants explode with leaf diseases and start to fall apart.
After the hail
Many people from across the state and sometimes the nation are asking how the hail-damaged crops and people are fairing. News traveled far and fast. Maybe those people have begun to realize that food isn’t raised in the grocery stores, instead it has to be raised by farmers who are hoping to make a return on their expenditures and labor each year.
Right now the news is not so rosy in both major hailed areas. The first stretch in northeast Iowa that was hailed on July 24 actually reaches about 50 miles into Illinois.
In many fields there were 50 percent defoliation in that storm early in the grain filling stage. Damage to those acres range from yielding a few bushels less to totally destroyed.
With the big Aug. 9 storm that tracked along U.S. Highway 20, the damaged plants have really begun to show the effects of the severe pounding they received. The corn stalks that took three or more big hail hits began turning brown by the following Friday. Stalk rot set in or too much moisture loss occurred with the deep bruises. Hail adjusters got to many of the fields quicker than the expected three to four weeks.
In many fields they only had to spend a minute or two to determine that there had been a complete loss. That actually made it easier for the growers as they didn’t have to go through yield checks or making comparisons. I was in the Callender area on Monday and guys were running their stalk shredders to knock the dead plants down and begin their tillage trips.
Ears that had been bashed by the big hail have now had the kernels in the damaged half decay and turn brown. Getting that grain to store through next summer will be very difficult and most combine operators will be advised to run their fans at full speed to clean the grain as much as possible.
Unfortunately there aren’t enough cattle feeders around to take advantage of such damaged grain.
Kernel abortion
Currently corn growers in the southwest and northwest ninths of the state can rightly and proudly boast that they have perhaps the best looking corn crops they have seen with the caveat that they have had to put effort into controlling the leaf diseases.
Rainfall amounts and timings were about perfect and nitrogen losses were at a minimum. In the other portions of the state it has become easy to see that most ears have lost from 10 to 20 rings of kernels around the ear due to several factors, with most of those being out of human control. Those long “tipbacks” are now very prominent in many fields and represent lost yield potential.
In most years the tips tell us whether or not enough kernels were planted. This year they tell of insufficient nitrogen, tissue loss due to diseases and hail, or weather that was persistently too cool and cloudy. At the time of the Pro Farmer crop tour, corn yields were assessed based on ear populations and ear size. Due to the immature crop it was impossible to accurately assess the final size of the ears, thus this tipback was not incorporated into the yield projections.
It is very common to find tipback of 1 to 4 inches on many ears and the second ears that were forming typically shrunk back completely.
Leaf diseases
During many days during July and August the skies were filled with aerial applicators applying fungicides and insecticides. Now is when you can go into your corn fields to see if those applications seem to be paying off. Too many disease lesions represent lost leaf tissue, which means lower capacity to produce sugars. Separating kernel abortion due to leaf diseases from that due to cold and cloudy conditions is impossible.
Over the past two weeks parts of eastern Iowa picked up as much as 18 inches of rain and diseases such as Anthracnose, Fusarium, Northern, Physoderma, and even Eyespot continued to increase in severity. Thus plants are continuing to melt down and plants are dying in those fields.
The old axiom and goal that plant breeders used to strive for was to produce a plant that had a brown husked ear on a green plant. Now due to several factors we have a high percentage of the fields containing mostly plants with a green ear where the top and bottom parts of the plants have yellowed or browned.
In 2008 that degeneration led to a situation where much of the corn still left in the field on Oct 27 was flat on the ground. Is that progress or what?
Soybean crop size
Forty five degree temps were expected to drive aphids from the bean fields. Currently the numbers have declined in most fields. I have found a few fields still with over 100 aphids per plant, but with the good moisture situation I’m not too worried about them at this date.
SDS and white mold are now appearing at varying levels in fields. The level of severity ranges from light and spotty to killing all the plants. The former is appearing in compacted areas where soil conditions would have been saturated during May or June.
WM is worst in taller beans where air movement was minimized and vegetation was lush. 2009 was not expected to be a bad WM year though. Curative treatments at this stage don’t exist for either problem.
Management steps need to be identified and adopted to avoid similar problems in 2010.
Jimmy Buffet
On a good note, I ended up Friday night in eastern Iowa, enroute to an open-air music hall just east of Delevan, Wis., on Saturday. One item remaining on our bucket list was going to a full-length Jimmy Buffet concert.
He and his 16-piece Coral band were there in their Hawaiian shirts and shorts playing their laid-back, Caribbean-themed music. The first half of the show was great and went quickly.
The musicians returned from halftime wearing coats. Jimmy Buffet concerts are well known for their tailgating and partying, but that was all made difficult with the rain and cold weather.
The comfortably dressed were wearing three or four layers of clothing. His best line to the people in the crowd was that he hoped that Wisconsinites would have their summer arrive before winter returned.
Good luck with field scouting and avoiding frost.
Bob Streit, who lives west of Ames, is a crop consultant.