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Articles from 2011 In July


Long Silks Are Seen, What Does It Mean?

Long Silks Are Seen, What Does It Mean?

Very hot days and warm night temperatures the last couple of weeks concern agronomists and corn growers. Unfortunately, this period of hot weather occurred during tasseling and silking. However, the USDA-NASS July 25, 2011 Iowa Crops & Weather report indicates that 80% of the state's corn crop was still in good to excellent condition. And 90% of the crop had tasseled and 75% silked – both slightly behind last year but ahead of the five-year average. 

"I've heard several accounts, both in Iowa and other states, of longer than normal silks this year. I hope these accounts are rare," says Roger Elmore, Iowa State University Extension agronomist. "Silks elongate an inch or more per day until they intercept pollen and the ovules are fertilized. Six inches of silk extending from ears, like I've seen in photos from central Iowa, could indicate four to six days of growth without pollination occurring. Silks remain viable for up to 10 days and turn brown and separate from ovules when ovules are fertilized."

Here's what happens during pollen shed and silking 

In older hybrids, pollen shed usually preceded silking, explains Elmore. Since stress affects silking more than pollen shed, high temperatures, especially when coupled with moisture stress, resulted in barren ears. Pollen shed and silking usually happen simultaneously with modern hybrids and in many cases, silks may appear before pollen shed. This is one of the mechanisms that resulted in greater stress tolerance with modern hybrids. Silks develop first from near the butt of the ear and then proceed progressively to the tip.

Pollen shed occurs first from anthers that protrude from near the tip of the main tassel stem, he adds. Subsequently, shed moves progressively down the main tassel and from the tips of tassel branches toward the main tassel stem. The last anthers to shed pollen are those on the lowest tassel branches near the main tassel stem. "Incidentally, scientists record the time difference between pollen shed and silking as a measure of stress among hybrids and/or experimental treatments. We call this the anthesis-silking interval or ASI," notes Elmore.

What do long silks suggest?  Silks stop growing and turn brown when ovules they attach to are fertilized. If all anthers on all plants have shed pollen and silks are still yellow-green and growing, kernels on the ear remain unfertilized. Harvestable kernel numbers will be reduced unless there is another source of pollen nearby. Yield potential will be compromised.

Husk gently and shake ears. Kernel set should be "easy" to determine after completion of pollen shed. As mentioned earlier, browning of silks indicates successful ovule fertilization. If yellow-green silks are obvious, gently remove husks to expose silks and kernels. Hold the ear horizontal and shake or roll it carefully. Silks will detach from fertilized ovules. Silks remaining attached to ovules indicate that those ovules were not fertilized and thus will not produce kernels. Tip kernels often are not fertilized.

Heat Wave Has Killed Up To 4,000 Iowa Cattle

Heat Wave Has Killed Up To 4,000 Iowa Cattle

As many as 4,000 Iowa cattle have died in the recent heat wave, the Iowa Cattlemen's association reports. ICA conducted a poll of its members and came up with this estimate. Up to 3,000 of the deaths occurred in eastern Iowa, says ICA spokeswoman Dal Grooms. She says totals from northwest Iowa push the number of cattle deaths to nearly 4,000.

Iowa had heat indexes of 110 degrees or higher from July 18 to 20. The heat broke on July 21 and the state received rainfall in a number of areas. But the heat index climbed to over 100 degrees again the last few days of July and a heat advisory resumed in central and southern Iowa.

The stifling heat could affect the fertility of bulls and the ability of heifers to stay pregnant. "The heat really knocks down the fertility of bulls and with heifers and cows, it's the early time of pregnancy and there is a question of whether they will stay pregnant because of heat stress," Grooms says. "We won't know the answer to that until October," when the animals are checked by veterinarians.

Iowa, which had about 1.2 million cattle on July 1, 2011 is the fifth-largest cattle-producing state in the nation.

Producers are taking steps to cool off their cattle from extreme heat

Grooms says farmers are doing all they can to protect their animals but cattle are especially vulnerable as they don't sweat and rely only on respiration. "I've talked to producers who've been out there just constantly looking for things to do to protect those cattle," she adds. "When it gets to be hot and humid like this, it's very difficult to stop all losses." Some parts of the state have had six or seven consecutive days with temperatures in the mid to upper 90s and heat indexes as high as 110 degrees.

Farmers have set up mist systems, industrial size fans and additional shelter in an attempt to cool off their cattle. She says the problems could persist into the fall. This is breeding time for cattle and the heat causes lower fertility for bulls and difficulty in the early stages of pregnancy for cows and heifers.

"Just because it finally cools off, those stressors don't go away," Grooms notes. "So producers will be watching their animals for quite a few weeks yet to make sure they can get them back to health." The reason most of the cattle deaths were reported in eastern Iowa, is because that part of the state didn't receive as much rain as other parts of the state.

Report livestock death losses to FSA for possible indemnity payment

You need to document and report cattle death losses from the heat to your local USDA Farm Service Agency office. You may be eligible for payment through USDA's Livestock Indemnity Program or LIP.

LIP only provides 30 days to report a loss after it has occurred. "While there are exclusions in the program, it is critical that producers make a timely 'Notice of Loss' report so they can be included if they qualify," says Grooms. Once a report is made and livestock continue to succumb because of the same weather event, those numbers can be included for the event.

ICA recommends producers document their losses, as well as the measures they took to protect the cattle. "Rendering truck receipts, photos and third party verifications from veterinarians, extension personnel or insurance adjusters are important, as is noting the approximate weight of the cattle that died. Likewise, take photos of your sprinkler systems, pen set-up and shade," says Grooms.

USDA indemnity program can provide up to 75% of value of the animal

The 2008 farm bill included LIP, which provides benefits to producers for livestock deaths in excess of normal mortality caused by adverse weather. Details are available from FSA, the USDA which administers the program. In most cases, the livestock indemnity program will provide coverage up to 75% of the value of the animal.

For the LIP payment, producers must file an "Application for Payment" with FSA. LIP is scheduled to close on October 1, and continued funding for it is unsure. "We encourage cattle producers to make that 'Application for Payment' as soon as they think their herd is fully recovered from the effects of this heat," she says. That is the time to also bring documentation in to the FSA office. The indemnity program may not cover everything you incur with such a loss, but it does keep this situation from becoming a financial disaster.

Stemmy Hay May Affect Best Use

Stemmy Hay May Affect Best Use

This is not only a tough and strange year for corn and soybean producers, it's also a tough year for hay producers, whether you're making hay for your own animals or to sell to someone else.

The first cutting tended to be made late, past prime on maturity, especially in alfalfa. This tends to results in rank growth which may have more stems and less leaves than you might normally expect. Feeding value should still be good on pure alfalfa, however.

Chris Parker, Morgan County Extension ag educator, believes the best policy is to test hay every year to know exactly what nutrient content it contains. He typically uses a probe, available at many extension offices, to bore into several bales. Then he mixes the cores into one sample and sends it to a commercial lab for forage analysis. Samples typically cost $10 to $15 to run.

The results will reveal protein content, amount of fiber and relative feed value. For relative feed value, the base is 100. Hays above that mark should let many animals perform well. The highest values are often the hay you would want to set aside or sell to someone with lactating animals. The lower testing hays are still usually sufficient to sustain dry cows in dairy and beef cattle through the winter.

The second cutting was also made late in many cases as the rain continued through June in many areas. It simply wasn't possible to cut the hay at the ideal stage, which is about 10% bloom for alfalfa and boot stage for grass. As a result, even many of the second-cutting hay samples that parker has seen contain more stems than usual. Fiber content may be high, but if the hay was harvested correctly, often with tedding and raking while he hay was still not so dry that it promoted leaf shattering, those hay types could still test relatively well.

Both the first and second cuttings were of ample quantity due to all the rain that promoted growth. Much of the first cutting was round-baled, partly because it was more rank, partly to get it up before it rained again.

So whether there will be a hay shortage or not depends upon who you talk to. With the sudden switch to dry weather, third and fourth cuttings of legume hay may be short on quantity. However, since the first two cuttings were plentiful, there should be enough hay, or at least that's what many hay growers believe right now. Finding the quality you want might be a tougher challenge.

What Does  Heat and Drought Do To Corn

What Does Heat and Drought Do To Corn

A stretch of roughly two weeks of 90-degree plus weather with lots of humidity, occurring in the last half of July, has many people wondering and asking questions about corn pollination and development. Normally, it's the tail end of the critical period for corn. This year, because planting was delayed, it hit at the heart of pollination and fertilization for many fields. There are still fields yet to pollinate, especially in eastern Indiana. If you want to know where the younger, shorter corn is we talk about from day to day, head east of Indianapolis 30 miles or so, then drive north or south, take your pick, and it won't be long before you find those fields, either just pollinating or yet to pollinate.

To understand the total effect on this year's crop, go back to a near-record wet April, which delayed planting. May and June were also cool. Crops planted in May were often planted between storm systems, usually in soils that were slightly wetter than you would prefer. Now in mid-summer comes extreme heat and drought. How is corn being affected by this environment?

Obviously, Mother Nature is not being kind to this year's corn crop. The heat helps the late corn catch up, but temperatures higher than 86 degrees F actually cause stress, not more growth. That's why 86 degrees is the maximum allowed in the growing degree days formula that attempts to estimate how fast corn will develop during the season.

The fields which were planted earlier are shedding or did shed pollen in the heart of the heat wave. They are also silking. Extreme heat and drought can delay silk emergence. If the delay is too long, pollen may be gone before the silks emerge. Cases of this have not been reported so far, but it is a possibility in this kind of summer.

Leaves will roll up. That's actually a good thing. It is a defense mechanism of the corn plant to reduce the amount of water loss by evaporation from the leaves during the day. Some hybrids that don't roll their leaves, or don't roll them as much, may get sun-burnt. Use this as an opportunity to select hybrids with heat and drought stress for the future. Certainly don't knock down a hybrid just because the leaves roll up.

In extreme heat and drought, plants may run from optimum grain yield production to a survival mode. The plant's goal is to make as many kernels (with embryos, ie babies) as possible. If this happens expect the ears to start aborting kernels at the tip first. The plant is trying to make sure the remaining kernels become fully developed with a viable embryo.

For every three aborted kernels, yield my drop about one bushel per acre. Let's hope for cooler weather, but not too cool, plus rain so we end up with decent crops. (Nanda is director of genetics and technology for Seed Consultants, Inc. Reach him at Nanda@seedconsultants.com or 317-910-9876.

Hear The Latest at Strip Till Expo

Hear The Latest at Strip Till Expo

Hear the latest University of Minnesota research and information on strip tillage and see strip-tillage equipment in action through field demonstrations at the 2011 "Minnesota Strip Till Expo" on Friday, August 5, at the College and University Center in Owatonna.

This event will run, rain or shine, from 9:00 to 3:30, with registration and Exhibits starting at 8:30 a.m.. Admission to the Expo is free and food will be available for purchase on-site. This program is brought to you by University of Minnesota Extension and Riverland Community College.

Field demonstrations by major manufacturers of strip-tillage equipment will run from 9:00 to 11:00 and again at 1:00 to 3:00. Educational presentations by University researchers and Extension Educators on the economics, soil benefits, and proper management of strip tillage will run from 10:00 to 12:00 and 1:30 to 3:30. From 12:15 to 1:00, a panel of strip-tillage producers will discuss their experiences and share tips with attendees. The Iowa State University "Conservation Station" will also be present from 10:00 – 2:00, offering demonstrations including a rainfall simulator. Attendees can visit vendor and informational booths throughout the day. For further details, visit http://z.umn.edu/stexpo2011.

Besides many environmental benefits, conservation tillage practices, such as strip-tillage, can yield economic benefits as well. Fuel costs can be reduced as trips across the field are decreased and fertilizer costs can be decreased if phosphorus fertilizer is banded instead of broadcast.

With fall strip tillage, a zone typically 5 to 9 inches deep and 7 to 10 inches wide is tilled in the crop row, while the area between rows is untouched. The crop is subsequently planted into the cleared strips in the spring. Strip-tillage addresses a common concern of conservation tillage related to soil warm-up in the spring by clearing residue in the plant row while maintaining high residue levels overall.

The expo is a great opportunity to learn more about strip tillage and current research results, to compare what equipment might work best for you, and to learn from others currently practicing strip tillage to help fine-tune your management practices.

For more information contact Brad Carlson at 507-389-6745 or email bcarlson@umn.edu.

-By Lizabeth Stahl, U-M Extension Educator in Crops

U of I Warns Goss's Wilt Is Spreading Across Much of Illinois

U of I Warns Goss's Wilt Is Spreading Across Much of Illinois

Goss's wilt is making a widespread appearance across Illinois, says Suzanne Bissonnette, director of the University of Illinois Plant Clinic.

Tests have now identified Goss's wilt in Sangamon, Knox, Livingston, Bureau, Edgar, Shelby, Woodford and Piatt counties.  

"In the past two weeks, we've received numerous field corn leaf samples as growers and agriculturalists are noticing the dramatic symptoms in fields across the central and northern parts of the state," she adds.

Prior to 2011, Goss's wilt has been observed only sporadically in Illinois, explains U of I Extension plant pathologist Carl Bradley. While the bacterial disease was positively identified in a few fields in the 2010 growing season, it appears to be much more widespread this season.

"Bacterial diseases require some type of wounding to infect a plant," Bissonnette adds. "Goss's wilt, caused by the bacterium Clavibacter michiganense subspecies nebraskensis, finds easy infection from tissue damage after hail, high winds and heavy rainfall."

Fields that are corn-on-corn, fields that have detected or undetected Goss's wilt from previous seasons, fields with high corn residue, and fields with weed hosts such as green foxtail or shattercane are at a higher risk for infection.

Leaf symptoms of this disease appear as large tannish to gray lesions that run lengthwise on the leaves. Within the lesions are dark flecks that are dark forest green or black in color. These flecks are frequently referred to as "freckles." 

Plant wilt can also be a symptom because the bacteria infect and effectively clog the xylem in the plant. On wilted plants, splitting the stalk may show dark streaking of the vascular tissue.  This is easiest to see if you cut the stalk at about a 45-degree angle.

Growers shouldn't assume that if their corn is exhibiting bacterial symptoms that they have Goss's wilt, Bradley adds. Another bacterial disease of corn in Illinois, Stewart's wilt, causes very similar symptoms.

In order to properly diagnose this disease, send suspicious samples to the U of I Plant Clinic. Visit http://web.extension.illinois.edu/plantclinic for more information. In states where the disease occurs regularly, yield losses of up to 50% in very susceptible hybrids have been noted.

Research indicates that dent corn inbred A632 and hybrids in which this and related inbreds are used are highly susceptible, she adds.

No in-season control options are available to protect against Goss's wilt infection or to reduce disease spread within a field. Foliar fungicides are not effective for bacterial infection either.

"The best method of controlling Goss's wilt is to plant corn hybrids with high levels of resistance," Bradley adds. "Check with your seed dealer to obtain Goss's wilt ratings. Management for next season should include tillage to bury infected residue, weed host management, and rotation to a non-host crop."

For more information, read The Bulletin online at http://ipm.illinois.edu/bulletin.

Soybean Aphids Starting to Increase In South Dakota

Soybean Aphids Starting to Increase In South Dakota

South Dakota State University researchers are seeing more soybean aphids in monitoring plots.

"We've started to see an increase in aphid numbers, with some fields approaching or meeting the threshold of 250 aphids per plant," says Kelley Tilmon, South Dakota Cooperative Extension and research soybean entomologist.

A number of fields have fairly low aphid counts per plant, but with a high infestation rate -- a high number of plants with at least some aphids on them.

"Those are fields to watch carefully," Tilmon says. "The recent heat may have slowed them down some, but when conditions moderate they can pick up where they left off. If you haven't scouted for aphids in your fields recently, this would be a good time to take another look."

Tilmon encourages producers to scout fields at least weekly.

"Scouting is the most important thing producers can do to help manage this pest. When conditions are favorable, sub-threshold populations can reach threshold in a matter of days."

SDSU research has established a decision threshold of 250 aphids per plant for South Dakota, which applies through the end of the R5 stage, or the beginning seed/seed fill growth stage in soybeans.

The decision threshold of 250 aphids per plant is not the actual economic injury level. The injury level is closer to 650 aphids per plant.

"Making a decision to treat at 250 gives you about a week to line up treatment before the injury level is reached," Tilmon says.

Threshold and scouting guidelines are available at http://www.sdstate.edu/ps/extension/entomology/sba/pubs.cfm.

Producers can also visit the Northern Plains IPM Guide (www.npipm.org) for Cooperative Extension Service advice on the biology and management of a number of soybean insects, available on the web or as free downloadable apps for iPhone and Droid.

Tilmon cautions producers to weigh several factors when deciding whether to treat.

"The economic injury level we use is calculated to balance potential yield gains against the cost of treatment so you come out ahead. You sometimes hear sales advice to throw some insecticide into your tank mix even when aphid numbers are low, 'just in case.' But even when the product is cheap, you can actually be buying yourself extra problems," she said.

Unwarranted insecticide application early in the season opens the door for aphid resurgence by killing beneficial predators like ladybeetles, leaving the fields unprotected from aphid regrowth and immigration. Later in the season, insecticides may cause secondary pest outbreaks. For example, spider mites start to be a problem in hot, dry weather.

"If you need to spray for aphids later in the season, avoid pyrethroids, which can flair mites," Tilmon advises.

Source: SDSU

Commodity Board Election Results Are In

Commodity Board Election Results Are In

The Illinois Department of Agriculture today announced winners of the July 6 state commodity board elections.  

The elections filled positions on three boards:  the Illinois Corn Marketing Board, the Illinois Soybean Program Operating Board and the Illinois Sheep and Wool Marketing Board.

"Congratulations to those who were elected," Agriculture Director Tom Jennings says. "It's an honor to be chosen by your fellow producers to represent their interests when these boards decide how best to spend industry checkoff dollars."

Checkoff dollars come from assessments levied at the first point of sale. State law sets the assessment for corn at 3/8 of 1 cent per bushel.  For soybeans, the rate is 1/2 of 1% of market value and, for sheep and wool, it is 2 1/2 cents per pound.

The newly-elected board members will serve three-year terms.  A list of the winners for each commodity board follows:

 

Illinois Corn Marketing Board

District

Counties Represented

Director

1

Boone, McHenry, Lake, DeKalb, Kane, Cook, DuPage, Kendall, Will                        

 

Glenn Ginder, Peotone

4

Whiteside, Lee, Bureau, Stark, Marshall, Putnam

James A. Rapp, Princeton

7

Woodford, McLean, Dewitt, Macon,

Piatt, Moultrie

William Christ, Metamora

 

10

Scott, Morgan, Sangamon, Greene,                 

Jersey, Calhoun, Macoupin    

Bill Long, Franklin

 

13

Marion, Clay, Richland, Lawrence, Jefferson, Wayne, Edwards, Wabash, White

Donald Duvall, Carmi

 

 

 

Illinois Sheep and Wool Marketing Board

District

Counties Represented

Director

1

Jo Davies, Stephenson, Winnebago, Boone, McHenry, Lake, Carroll, Ogle, DeKalb, Kane, Cook, DuPage, Whiteside, Lee

Barbara Hintzche, Rochelle

4

Bureau, Putnam, LaSalle, Stark, Marshall, Peoria, Woodford, Tazewell

Appointment

7

Madison, Bond, Fayette, Effingham, Jasper, Crawford, St. Clair, Clinton, Washington, Marion, Jefferson, Clay, Wayne, Richland, Edwards, Lawrence, Wabash, Randolph, Perry, Franklin, Hamilton, White, Monroe, Jackson, Williamson, Saline, Gallatin, Union, Johnson, Pope, Hardin, Alexander, Pulaski, Massac                            

Appointment

 

 

 

Illinois Soybean Program Operating Board

District

Counties Represented

Director

1

Jo Davies, Stephenson, Winnebago, Boone, Carroll, Ogle, DeKalb, Lee

 

Appointment

5

Knox, Peoria, Marshall, Putnam, Tazewell                             

Dan Farney, Morton

 (write-in candidate)

7

Ford, Iroquois, Vermilion

Michael Marron, Fithian

9

Mason, Logan, Cass, Menard, Morgan, Sangamon

Tim Seifert, Auburn

 

12

Pike, Scott, Calhoun, Greene, Macoupin, Jersey           

Mark Sprague, Hull

13

Montgomery, Bond, Fayette, Marion

Gary Berg, St. Elmo

 

Manure Expo Panelists Describe Value of Manure to Cropland

Manure Expo Panelists Describe Value of Manure to Cropland

There was a time when livestock producers considered manure as a waste problem. With skyrocketing commercial fertilizer costs in recent years, both livestock and crop producers now think of manure as a valuable resource.

"Manure used to be a waste," Andy Scholting, manager of Nutrient Advisors, LLC in West Point, told a group of producers recently at the North American Manure Expo held in Norfolk. "But now it has value," he said.

The key is understanding the actual nutrient content of the manure, said Scholting, who was part of a panel of crop and manure experts who spoke at the expo. "It can be extremely valuable, but we want to see multiple analysis results and averages over time" to determine the actual nutrient value of the manure.

"It is dangerous to only use a high testing sample and then get caught with yellow crops" because the manure did not include enough nutrients to carry the crop to harvest time, he said.

When looking at the nutrient value of manure, producers are usually considering nitrogen, phosphorus and potassium, along with zinc and sulfur. They really want to know what is available to the crop during the first year after application.

"It's easy to quantify the fertilizer value of manure," Scholting said. Adding manure to crop fields also increases the water infiltration rate, so more rainfall is absorbed into the soil and less precipitation runs off the field. "Manure is an investment that will pay big dividends over time. Many of our clients are seeing 20-30 bushel yield advantages in their corn," he adds.

"You can put a value on micronutrients," said another panelist, Abe Sandquist, owner of Natural Fertilizer Services, Inc. in Woodbine, Iowa. "What goes in is what goes out. So the value of the manure depends on what is being fed to the livestock producing it."

There are cropping issues to consider, including salt content, weed seed, rocks and compaction issues during manure application. Modern herbicide programs have reduced the worries about weed pressure, Scholting said.

Crop producers who are shopping for manure from their neighbors should consider transportation costs, said panelist, Kendall Bonenberger, president of Environmental Sciences, Inc. in Lincoln. If someone else is applying purchased manure, it is important that they have competent, knowledgeable applicators, he told the group.

Farmers also need to be considerate of where they are stockpiling their manure, and if they are spreading wet manure products, they should communicate with neighbors about odor concerns and show common courtesy, said Bonenberger.

Sandquist said that farmers can figure commercial fertilizer costs from $90 up to $150 per acre, if they expect corn yields of 200 bushels per acre. So, solid cattle manure fertilizer equivalent valued at $25 per ton carries great value these days, not only for the current crop year, but for subsequent cropping seasons as well.

For more information, contact the panelists: Scholting at 402-372-2236, Sandquist at 712-592-1905, or Bonenberger at 402-423-9696.

Crops Go On Defense

Crops Go On Defense

Corn leaves are rolling. Soybean leaves are flipping. Crop plants go into a defensive mode against the sun and heat.

"For crops, the drought threat is serious," says Bill Wiebold, University of Missouri Extension agronomist. "Yields drop. Plants die.

"Once corn plants turn blue-gray instead of dark green, they are within about three days of death," he says. Plants defend themselves for a while, but with no rainfall and continued high temperatures, the plants die. At first, the plants stop filling the ears and pods with grain. Then they go into a survival mode. Soybean plants can set new flowers with late rains. Corn does not.

As the hot, dry weather continues, corn leaves "roll." By rolling, the leaves reduce their exposed surface to sunlight. Also, the air inside the rolled leaves helps them retain some moisture and stay a bit cooler.

Soybean leaves change orientation with the sun to be efficient solar collectors. In normal weather, all leaves are oriented toward the sun for photosynthesis, which manufactures sugars that feed the plant and fill the seedpods. As the plant becomes stressed, the leaves turn parallel to the sunbeams and stop collecting solar energy.

"You can look right down into the field canopy and see the ground," Wiebold says. "Normally, with canopy closure, you can't see the ground."

As drought stress continues, the leaves flip upside down. The underside of the soybean leaf is more white than green. The white surface reflects sunlight back into the atmosphere.

The big issue now is evapotranspiration. The plants need one-quarter to one-third inch of water a day to keep functioning. With the lack of rainfall, the plants pull all available moisture out of the soil. Moisture helps cool the plant and moves plant sugars from the leaves to the seeds.

Several things begin to fail all at once when the plant goes into heat stress, Wiebold says. "Old farmers say that hot weather makes a corn crop. But that is true only to a point. When temperatures get much over 88 degrees, the plants are harmed."

The big hazard is hot nights, Wiebold says. When air temperature remains in the 80s at night, the plants continue respiration instead of shutting down. That plant activity at night, when photosynthesis has stopped, burns sugars that were made during the day. When sugar creation slows in the hot daytime temperatures and plants burn sugars at night, there is a net energy loss.

The corn stalks can look, from afar, to be normal. However, if the corn was hit by hot, dry weather during pollination, the ears may not be full of kernels up and down the cob.

"This may be a rough year to grow double-crop soybeans," Wiebold adds. "I've seen some soybean leaves appearing above the wheat stubble. But in this drought, the soybean plants seem to shrink." Normally, about July 1, double-crop soybeans are drilled into stubble fields left after wheat harvest.

While farmers and their crops don't thrive in hot, dry weather, some insects do. "Grasshoppers are moving from field edges out into the crops," says Wayne Bailey, MU Extension entomologist. "Grasshoppers eat both corn and soybean plants. I'm getting a lot of phone calls.

"Spider mites are showing up in soybean fields," Bailey adds. "They are tiny and hard to see, but first symptoms might be webbing in a circular patch. If you get close, you can see reddish moving dots, especially under upper leaves. Spider mites suck juice out of the leaves at a time when the plants need moisture."

MU Extension specialists hold weekly teleconferences with regional agronomists across the state to exchange crop condition updates.

Source: MU Cooperative Media Group