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Degree Days - What A Year It Was, Richard Pope Nov 2010

Degree Days - What A Year It Was, Richard Pope

Integrated Crop Management News

Heat or maybe lack of heat is a better description to use in this recap of the growing season. The degree day departure from average graphic shows how the season progressed by crop reporting district.


More Than 800 Scn-Resistant Soybean Varieties Available To Iowa Growers, Gregory L. Tylka Nov 2010

More Than 800 Scn-Resistant Soybean Varieties Available To Iowa Growers, Gregory L. Tylka

Integrated Crop Management News

Soybean varieties that are resistant to the soybean cyst nematode (SCN) are extremely important for managing this damaging pest. In general, SCN-resistant soybean varieties yield greater than susceptible varieties in SCN-infested fields, and resistant varieties keep SCN population densities from increasing, which ensures profitable soybean production in future years.


When To Sample For Nematodes On Corn - It Depends, Gregory L. Tylka Oct 2010

When To Sample For Nematodes On Corn - It Depends, Gregory L. Tylka

Integrated Crop Management News

A recurring question often asked concerning plant-parasitic nematodes that feed on corn is, “When should samples be collected to check for these pests?” The answer depends on the details of each specific field situation. In most cases, fall sampling to test for nematodes that feed on corn is not recommended.


Enjoy The Fall Weather –Take A Walk And Collect Some Soil Samples, Gregory L. Tylka Oct 2010

Enjoy The Fall Weather –Take A Walk And Collect Some Soil Samples, Gregory L. Tylka

Integrated Crop Management News

Once harvest is completed, a very productive way to enjoy the fall weather is to collect soil samples for soybean cyst nematode (SCN). In the 1990s and much of the past decade, fall soil sampling for SCN was strongly recommended as a way to scout fields for the presence of this pest. If fields have not yet been tested for SCN, soil samples should be collected for this purpose. But many fields infested with SCN in Iowa likely have already been discovered.


Warm Fall Temperatures, Scn And Winter Annual Weeds, Gregory L. Tylka Oct 2010

Warm Fall Temperatures, Scn And Winter Annual Weeds, Gregory L. Tylka

Integrated Crop Management News

We have had a wonderfully sunny, warm, dry fall so far this year. How could anyone complain about the weather? Leave it to a nematologist. Yesterday's ICM News article reminded growers and agronomists to delay application of anhydrous ammonia fertilizer until soil temperatures drop below 50F. It turns out that 50F is also an important temperature to consider for soybean cyst nematode (SCN).


Flooded Grain And Other Harvest Issues, Charles R. Hurburgh, Roger Elmore, Alison E. Robertson Oct 2010

Flooded Grain And Other Harvest Issues, Charles R. Hurburgh, Roger Elmore, Alison E. Robertson

Integrated Crop Management News

Harvest is underway and a few issues stemming from the unusual weather patterns last summer are coming up. On September 30 the Iowa Department of Agriculture and Land Stewardship (IDALS), as the state representative for the U.S. Food and Drug Administration, issued a statement saying that grain submerged (over the grain) in flood waters was to be considered contaminated and therefore not eligible for entry into food-feed markets. Ethanol is a feed market because of the dried distillers grains with solubles (DDGS). This is the same policy that was used for grain in storage that was submerged in 2008 ...


Towards A Successful Harvest: Stalk Rots And Standability Issues, Alison E. Robertson Sep 2010

Towards A Successful Harvest: Stalk Rots And Standability Issues, Alison E. Robertson

Integrated Crop Management News

It’s hard to believe the 2010 growing season is almost over. Most of the corn across the state is nearing or at black-layer, which means it is time to scout fields for stalk rots in an effort to evaluate standability and plan a successful harvest. Stalk rots are likely to be an issue this growing season. We have seen significant blighting of the leaves in the upper canopy predominantly from Goss’s wilt, northern corn leaf blight, gray leaf spot and anthracnose top dieback. When significant leaf blight occurs in the upper canopy, the risk of stalk rots increases ...


The 2009 Crop Won’T Quit – And Here Comes 2010, Charles R. Hurburgh, Alison E. Robertson Sep 2010

The 2009 Crop Won’T Quit – And Here Comes 2010, Charles R. Hurburgh, Alison E. Robertson

Integrated Crop Management News

Most of us would probably rather forget the 2009 crop, at least as far as storage and quality goes. Unfortunately, as we thought it might, this crop just kept on giving – headaches. The wet, incompletely developed and low test weight conditions led to about 50 percent shortening of the normal shelf life, at any moisture and temperature condition. Storage norms were covered in an ICM News article last fall, 2009 Corn Quality Issues – Storage Management.


Good Harvest In Corn Should Help Manage Soybean Sds, Xiao-Bing Yang, Shrishail S. Navi Sep 2010

Good Harvest In Corn Should Help Manage Soybean Sds, Xiao-Bing Yang, Shrishail S. Navi

Integrated Crop Management News

This year is one of the worst soybean sudden death syndrome (SDS) epidemics since the disease was found in Iowa in 1994. Preliminary research data suggest that corn has much to do with SDS pathogen and there are things we can do about the disease as we begin harvest. Management of SDS should start when we harvest corn fields.


Video Offers Guidance For Coping With Soybean Sudden Death Syndrome, Alison E. Robertson, Leonor F.S. Leandro Sep 2010

Video Offers Guidance For Coping With Soybean Sudden Death Syndrome, Alison E. Robertson, Leonor F.S. Leandro

Integrated Crop Management News

As soybean sudden death syndrome (SDS) continues to ravage Iowa fields in one of the worst outbreaks in many years, Iowa soybean growers are increasingly worried about the damage the disease will cause, while others are unsure whether their plants have been infected. To help answer questions and offer guidance in managing the disease, Iowa State University has produced a video that explains why SDS is so severe this season; tells how to assess and manage SDS; offers practical advice growers can follow now to prepare for next year; and highlights new and ongoing ISU research on the problem.


Answers To Questions About Soybean Sudden Death Syndrome In Iowa 2010, Alison E. Robertson, Leonor F.S. Leandro Sep 2010

Answers To Questions About Soybean Sudden Death Syndrome In Iowa 2010, Alison E. Robertson, Leonor F.S. Leandro

Integrated Crop Management News

Sudden death syndrome (SDS) is now among the top four yield robbing diseases in soybeans. From 1999 to 2004, average losses in the U.S. were estimated at $190 million a year, and the disease is spreading and intensifying. SDS has been widespread and severe in Iowa this growing season, generating many questions of researchers. The most frequently asked questions are included in the following series of questions and answers.


Soybean Sudden Death Syndrome In A Flood Year - What To Do Next, Xiao-Bing Yang Aug 2010

Soybean Sudden Death Syndrome In A Flood Year - What To Do Next, Xiao-Bing Yang

Integrated Crop Management News

Soybean Sudden Death Syndrome (SDS) is widespread in Iowa. This year has had one of the worst epidemics since the disease was found in Iowa in 1994. Severely infested soybean fields can be found in every region in Iowa. It is easy to spot brown patches caused by SDS while you are driving the highways. Fields with large portions of premature defoliation can be found in early August.


Common, Weird And Unusual Spots Showing Up On Corn, Alison E. Robertson, Laura C.H. Jesse, Fanny Iriarte Aug 2010

Common, Weird And Unusual Spots Showing Up On Corn, Alison E. Robertson, Laura C.H. Jesse, Fanny Iriarte

Integrated Crop Management News

There have been several recent reports of leaf spots showing up on corn in addition to the eyespot and Goss’s wilt reported earlier this growing season. Some of these are expected – Northern corn leaf blight and gray leaf spot, but some such as southern rust are a little less common, and others are just weird.


Be On The Lookout For Soybean Diseases, Alison E. Robertson, Daren S. Mueller Aug 2010

Be On The Lookout For Soybean Diseases, Alison E. Robertson, Daren S. Mueller

Integrated Crop Management News

While this season is progressing much quicker than last year, one thing is remaining the same – lots of rain. With the rain, several diseases are starting to show up or are expected to show up during the next month.


Mid-Season Soybean Diseases: Scouting And Management, Xiao-Bing Yang Jul 2010

Mid-Season Soybean Diseases: Scouting And Management, Xiao-Bing Yang

Integrated Crop Management News

This is another unusual growing season, with a cool and wet spring followed by the hot and rainy summer. The cool weather that continued into the first week of July suddenly changed when a heat wave accompanied with rainy days arrived. The hot and wet final two weeks of July remind me of the subtropical weather in the Gulf Coast of Louisiana where I did my graduate study and where foliar diseases are a major issue in crop protection each year.


Check Soybean Roots For Scn Females, Gregory L. Tylka Jul 2010

Check Soybean Roots For Scn Females, Gregory L. Tylka

Integrated Crop Management News

The soybean cyst nematode (SCN) is widespread throughout Iowa and surrounding states, and as much as 40 percent yield loss can occur from SCN damage without symptoms appearing. Symptoms typically are not apparent when temperatures are moderate and rainfall is adequate to excessive during the growing season.


Nematodes Damaging Corn This Year?, Gregory L. Tylka Jul 2010

Nematodes Damaging Corn This Year?, Gregory L. Tylka

Integrated Crop Management News

Currently, there is considerable interest and continued discussion among growers, agronomists and university researchers about plant-parasitic nematodes that feed on corn. To find out if these microscopic worms are damaging a corn crop, soil and roots must be collected and sent to a qualified laboratory to determine which specific nematodes are present and at what population densities (numbers).


White Mold Mushrooms Show Up, Xiao-Bing Yang, Shrishail S. Navi, Xun Li Jul 2010

White Mold Mushrooms Show Up, Xiao-Bing Yang, Shrishail S. Navi, Xun Li

Integrated Crop Management News

Over the last 10 days the weather was favorable for the production of soybean white mold mushrooms in Iowa. Yesterday we visited fields near Clear Lake in north central Iowa with crop consultant Dan Muff and found abundant white mold mushrooms in a continuous soybean field, which had a closed canopy with wonderful growth. The density of the mushrooms was very high, 3 apothecia/square foot, and soybean plants are likely to be infected. The early showing in such a large number in this field was due to early planting, good growth and a higher number of sclerotia from last ...


Summary: Foliar Fungicide On Corn In Iowa (2007 – 2009), Daren S. Mueller, Alison E. Robertson Jul 2010

Summary: Foliar Fungicide On Corn In Iowa (2007 – 2009), Daren S. Mueller, Alison E. Robertson

Integrated Crop Management News

Data from corn fungicide small plot trials conducted by Iowa State University faculty and staff, and on-farm trials conducted by the Iowa Soybean Association On-Farm Network, the ISU Corn and Soybean Initiative and the ISU Northwest On-Farm research program were recently collated and summarized.


Summary: Foliar Fungicide On Soybean In Iowa (2006 – 2009), Daren S. Mueller, Alison E. Robertson Jul 2010

Summary: Foliar Fungicide On Soybean In Iowa (2006 – 2009), Daren S. Mueller, Alison E. Robertson

Integrated Crop Management News

We recently collated and summarized data from soybean fungicide small plot trials conducted by Iowa State University faculty and staff, and on-farm trials conducted by the Iowa Soybean Association On-Farm Network, the ISU Corn and Soybean Initiative and the ISU Northwest On-Farm research program.


Start Checking Soybean Roots For Scn Females, Gregory L. Tylka Jun 2010

Start Checking Soybean Roots For Scn Females, Gregory L. Tylka

Integrated Crop Management News

Soybean cyst nematode (SCN) is a serious pest concern for soybean every season in Iowa. Current SCN management options include soil-applied nematicides and resistant soybean varieties. All are implemented at the time of planting. However, effective scouting during the growing season is the key to successful, integrated management of SCN.


Characteristics Of Corn Left Standing Through Winter 2009-2010 In Iowa, Alison E. Robertson, Gary P. Munkvold, Charles R. Hurburgh Jun 2010

Characteristics Of Corn Left Standing Through Winter 2009-2010 In Iowa, Alison E. Robertson, Gary P. Munkvold, Charles R. Hurburgh

Integrated Crop Management News

Very wet conditions in October 2009 and early snowfalls in November resulted in several thousand acres of corn left standing through the winter in Iowa. Considering the grain quality issues that ended the growing season, concerns were raised regarding the quality of corn left standing over the winter.


Scouting For Soybean Seedling Diseases, Xiao-Bing Yang, Shrishail S. Navi Jun 2010

Scouting For Soybean Seedling Diseases, Xiao-Bing Yang, Shrishail S. Navi

Integrated Crop Management News

Seedling diseases are one reason to use seed treatment. Each planting season, different weather patterns result in different seedling disease problems. This planting season has been smooth in general and seedlings have emerged in many soybean fields. So far, disease risk is lighter than last year. We did, however, observe some light occurrence of seedling disease from production fields around the central Iowa. Damping-off was also found in our research plots. It is now time to check your soybean fields to determine if there are any seedling disease problems.


Sampling Strip Trials For Corn Nematodes, Gregory L. Tylka May 2010

Sampling Strip Trials For Corn Nematodes, Gregory L. Tylka

Integrated Crop Management News

Many people currently are asking how to collect nematode samples from strip trials of corn treated with new seed-treatment nematicide products. Avicta® Complete Corn and Votivo™ are the two products commonly being compared. Avicta® Complete Corn, which was widely available to corn producers for the first time in 2010, is a combination of the Avicta seed treatment nematicide (active ingredient abamectin), a seed treatment insecticide and three seed treatment fungicides. Votivo™ is a biological seed treatment containing the bacterium Bacillus firmus that will be available in 2011.


2010 Soybean Rust Update, Daren S. Mueller May 2010

2010 Soybean Rust Update, Daren S. Mueller

Integrated Crop Management News

This could be the world’s shortest ICM News article. It could simply read “soybean rust, meh”. But I will take some time to explain. We have identified three critical steps that must happen for rust to get to Iowa. They are (1) to survive winters somewhere in the south, (2) build up inoculum (spores) where survival occurs and (3) movement of these spores to fields further north and successful infection of soybeans in those fields. These steps may need to reoccur several times for rust to get to Iowa.


Can Tank Mixing Fungicide With Post-Emergence Herbicide Increase Yield?, Alison E. Robertson May 2010

Can Tank Mixing Fungicide With Post-Emergence Herbicide Increase Yield?, Alison E. Robertson

Integrated Crop Management News

The early application of foliar fungicides to corn (V4-V7) is currently being encouraged by chemical companies across the corn belt. The idea is to tank-mix the fungicide with the post-emergence herbicide application and save on application costs. Furthermore, for additional cost savings, half or lower rates of fungicides are being marketed. It is my understanding that this early application of fungicide will not necessarily replace the VT/R1 application of foliar fungicide, rather it is an addition to the tassel/silking application.


Early Season Corn Nematode Scouting, Gregory L. Tylka May 2010

Early Season Corn Nematode Scouting, Gregory L. Tylka

Integrated Crop Management News

Plant-parasitic nematodes can be a pest concern for corn. Current corn nematode management options include seed-treatment and soil-applied nematicides; both are implemented at the time of planting. There are no effective management strategies to use after the corn crop has been planted, however effective scouting is the foundation to a successful, integrated nematode management program.


Scout For Early Summer Diseases, Xiao-Bing Yang May 2010

Scout For Early Summer Diseases, Xiao-Bing Yang

Integrated Crop Management News

Recent growing seasons have not been typical ones, and this season seems to follow this pattern. Each unusual season has unique disease problems. This year, early planted soybeans are in flowering stage and we are starting to see a different set of issues. There are three things to look for when scouting these fields.


Early Season Diseases Showing Up In Corn And Soybean Fields, Alison E. Robertson May 2010

Early Season Diseases Showing Up In Corn And Soybean Fields, Alison E. Robertson

Integrated Crop Management News

The widespread rain that has occurred across Iowa has been favorable for the development of early season disease in both corn and soybean. In corn, symptoms of anthracnose leaf blight (Figure 1) are common in corn-following corn fields. A very low prevalence of eyespot and common rust have also been seen in ISU fungicide trials. In soybean, brown spot (Figure 2) and bacterial blight (Figure 3) symptoms are becoming common.


Take Note Of Diseases In A Cool Spring, Xiao-Bing Yang May 2010

Take Note Of Diseases In A Cool Spring, Xiao-Bing Yang

Integrated Crop Management News

Producers in Iowa have had a good planting season. As of Monday, ISU agronomists reported near completion of corn and 50 percent of soybean planted in Iowa. So far this has been one of the most trouble free planting seasons I remember, with some similarities to last season.