C.O.R.N. Newsletter 2007-01

Dates Covered: 
January 10, 2007 - January 23, 2007
Harold Watters

Are Foliar Fungicides Economical for Ohio Producers Without Soybean Rust?

Authors: Anne Dorrance

Co-authors: Anne Dorrance, Dennis Mills, Bruce Eisley, Roger Bender, Greg LaBarge, Dave Mangione, Gene McClure, Steve Ruhl, Howard Siegrist, Dusty Sonnenberg, Alan Sundermeier, Harold Watters, Gary Wilson, John Yost, and Christian Cruz.

The use of foliar fungicides is a routine practice in the southern US, Tennessee, Arkansas, Georgia, Mississippi, Alabama and Louisiana to manage frogeye leaf spot, purple leaf stain, Southern stem canker, and aerial blight. In the north central region, none of these diseases are present at economic levels with one exception, frogeye leaf spot during the 2006 production season. The most common foliar pathogens in Ohio are brown spot and downy mildew. As of December 13, 2006 soybean rust has not been found in Ohio (infected leaves with sporulating pustules).

As part of our preparation for soybean rust, we have completed a number of different studies in Ohio:
1. Evaluated the combination of fungicide and insecticides in on-farm trials
2. Evaluated the impact of strobilurin-type fungicides on brown spot
3. Evaluated the effects of brown spot on soybean yield

The following is a brief summary of each of these studies.

1. Evaluation of the combination of fungicides and insecticides in on-farm trials.
For these trials large fields, 50 acres or more were selected. Producers and county extension educators applied treatments using their own equipment and harvested the plots. Data was collected 3 weeks after the last application on the incidence and severity of brown spot and aphids. The treatments included Quadris (6.2 fl oz/A), Warrior (2.56 fl oz/A); Quadris plus Warrior (same rates) and a nontreated strip. The study was treated in a randomized block design with 3 to 5 replications depending on the size of the field. There was no significant difference in the levels of brown spot at any of the locations during the two years of this study. During 2004, no aphids were found in any of the locations but during 2005, high levels of aphids could be identified in some of the locations.

Conclusion: There was no consistent advantage in the application of Quadris in these on-farm studies. Warrior provided excellent control of soybean aphids, however, timing of applications was better at the recommended time (250 aphids per plant) compared to applications made at the R3 growth stage with lower aphid populations. In two fields, aphid populations were low at the R3 growth stage and the fields required a second application or did not get the huge benefit of the insecticide.

Table 1. Comparison of Quadris and Warrior to the non-treated control during 2004 in on-farm trials. There were no aphids and very low levels of foliar feeding insects. Only at the Hardin and Wood locations, were the treatments significantly better than the control, and in these situations the increase over the non-treated was 5 and 3 bushels.

Yield difference (bu/A) from non-treated for Quadris + Warrior

Location/Cooperator Quadris + Warrior

Table 2. Five of the locations had very low or no aphid pressure during 2005. For these fields, Warrior was significantly better than the non-treated in Hardin and Licking counties.

Yield difference from nontreated (bu/A)

Table 3. Seven of the locations had very high aphid populations. For all but one location, treatments were significantly better than the controls. In these cases Warrior alone was providing the protection.

Yield difference from nontreated (bu/A)

2. During 2006, four soybean varieties were planted at the OARDC Northwest and Western Research stations. This study consisted of Headline, Folicur, Headline plus Folicur, Quadris applied at R3 and R5 growth stages and two non-treated treatments. The study was arranged in a split-plot design, where the varieties were replicated first, then for each variety, the fungicide treatments were also randomized.

Table 4. There was a significant difference among the fungicide treatments to one of the untreated plots – for the level of brown spot at the NWB location only, Headline, Folicur, Headline plus Folicur, Quadris and Headline at R3 followed by Folicur at R5. Disease levels were much lower at Western research station and were not significantly different.

Percent Leaf Area Affected at R5
Headline @ R3
Headline @ R5
Headline + Folicur @R3
Headline + Folicur @R5
Folicur @ R3
Folicur @ R5
Quadris @ R3

Table 5. Yield difference (bu/A) of fungicide treatments combined across four soybean varieties at two locations.

Yield difference from non-treated (bu/A).
All Cultivars Combined Northwest Western
Headline R3
Headline R5
Headline/Folicur R3
Headline Folicur R5
Folicur R3
Folicur R5
Quadris R3
Headline R3 Folicur R5

In both locations, fungicide treatments increased yields, albeit at 3.4 and 6.8 bushels at NW and Western from one untreated plot and 1.5 and 4.3 from the second untreated plot at the same locations.

3. For the final study, we assessed disease severity levels of brown spot across the season on four soybean varieties treated with Echo (chlorothalonil) at two locations. This study was also arranged in a split-plot design with the varieties replicated first and chlorothalonil treatments as the sub-plots. Note: this is not a labeled use of chlorothalonil, this study was done to determine the effects of brown spot. One to two week applications of Echo were applied beginning at V1 (first fully expanded trifoliate) until R6, full seed. There were ten treatments, one nontreated up to 10 total applications. Again, this is not a labeled use of chlorothalonil and is the type of study only suited for research farms.

Table 6. Echo reduced the level and severity of brown spot at both locations and increased yield by 4 and 2.8 bu/A at Western and Northwest respectively. Brown spot is a minor foliar disease of soybean in Ohio.

6a. Percent Leaf Area Affected by Brown Spot.
Number of Sprays Northwest Western
2 26.7 10.08
3 18.8 9.58
4 18.3 5.75
5 9.6 12.6
6 7.5 0.83
7 5.4 0.83
8 5.4 0.0
9 5.4 0.42
10 5.8 0.08

6b. Yield bu/A.
Number of Sprays Northwest Western
2 46.4 46.8
3 46.8 45.5
4 47.0 45.9
5 46.8 44.2
6 48.1 43.5
7 49.3 46.9
8 49.8 48.2
9 49.4 48.3
10 48.4 49.3

From all of these trials, fungicides, in the majority of cases increased yield. Sometimes this was difficult to measure and in other cases it was substantial (Headline during 2006 in Ross County, data not shown). We have demonstrated that many of these fungicide applications reduce the incidence and severity of foliar diseases as well as demonstrated efficacy on some of the minor foliar pathogens found in Ohio. However, the final question is, are these applications economically viable in today’s volatile soybean price market. Across all studies on average, we gained 3 bu/A. In order for application to be economically viable – soybean price must be $8.00 or higher and the gain must be consistently greater than 3 bu/A.

Table 7. Table illustrating the cost of application, the potential price for bushel and the possible gain in yield for most foliar fungicide applications.

Economics for Fungicide Applications
$/bu $4 $5 $6 $7 $8
+2 bu

Acknowledgements – Matt Davis, Joe Davlin, Drake Farms, Lamar Ratliff, Rettig Farms, Gary Shick, Kris Swartz, Nathan Verdier, BASF, Bayer CropScience, Sipcam Agro USA, Monsanto, Pioneer.


Compaction and Winter Tillage

Authors: Randall Reeder

The wet fall of 2006 has led into the warm wet winter of 2007. Many who wanted to do some tillage are forced to wait for the “right conditions”. We don’t have research on this rare situation, but let me offer some options to consider.

First, don’t make a bad soil problem worse by working it wet. Even if it freezes on the surface in the next week or so, resist the temptation to plow or subsoil if it is still wet underneath. Doing no tillage at all this winter is better than tilling too wet. It may be best to live with the deep compaction for a season and hope to correct it after the 2007 harvest.

Second, waiting until March or April and doing a light surface tillage may be a reasonable choice. Disease pressure will likely be worse this year than normal, and getting some soil mixed with crop residue will help. Light tillage will also help level out ruts and leave the field reasonably level for planting. Examples of shallow tillage equipment are the Phoenix harrow, Aer-way, and M&W Dyna-Drive. Make sure these are run just a couple of inches deep and do not kick up wet soil.

Third, work only the areas with ruts. This applies where only scattered wet spots were severely rutted. The main goal should be to smooth out the surface to eliminate or minimize standing water, and with luck allow the field to be planted normally.

Obviously, these options don’t apply to everybody. If you were able to get a cover crop established, such as ryegrass, it may help reduce compaction and dry out the soil.

2006 Northwest Ohio Corn Silage Test

Authors: Rich Minyo, Allen Geyer, Peter Thomison

In recent years, requests for information on corn hybrid silage quality and yields from producers and seed company representatives have been increasing. In 2006, we conducted a joint trial with Michigan State University (MSU) adding one Ohio silage location to Michigan’s two southern (Zone 1) silage locations. The Ohio test site was located in our Northwest Region at Hoytville (Wood County) The two MSU sites are located in Branch and Lenawee counties, which are on the Ohio/Michigan state line.

The test results from the three locations are treated as one region. The plots were planted with 4 row air type planters and maintained by each respective state utilizing standard production practices. The center 2 rows were harvested with MSUs self-propelled forage harvester. Silage tests were harvested uniformly as close to half milk line as possible. Near Infrared Reflectance (NIR) Quality Analysis was performed by MSU using their current procedures. Silage results present the percent dry matter of each hybrid plus green weight and dry weight as tons per acre. Other data presented include percent stand, the percentage of in vitro digestible dry matter, acid detergent fiber, neutral detergent fiber, crude protein and starch. Milk production in pounds per ton and pounds per acre are estimated using MILK2000.

A complete summary of the Ohio results is available online at: http://www.oardc.ohio-state.edu/silagetrials. More information on procedures and additional 2006 MSU silage test data can be viewed on the web at http://www.css.msu.edu/varietytrials/corn/corntrials.htm.
For more information on Ohio State’s crop variety testing, visit:

Two Upcoming Major Conservation Tillage Conferences

Authors: Randall Reeder

In western Pennsylvania

First is the Tri-State Conservation Tillage Conference held at West Middlesex, PA, on January 23. It will be held at the Radisson Hotel in West Middlesex, Pennsylvania, which is conveniently located at Exit 4B on Interstate 80, just east of the Ohio state line. The conference will start at 9:00 a.m. Early registration is $20.00 per person; after Jan. 12 it’s $25.00.

Topics and speakers include: “High Fertilizer Prices-How Much Should We Cut Back?” by Dr. Tom Bruulsema, Director of the NE Region for the Potash and Phosphorous Institute; “Nitrogen Management in Conservation Tillage Systems” with OSU Extension Soil Fertility Specialist Dr. Robert Mullen; “Improving Conservation Tillage Systems” by Dr. Wayne Reeves, USDA-ARS at Auburn, Alabama; and “What’s in the 2007 Farm Bill’s Basket”.

For more information or to register, contact Dianna Hendrick at the Penn Soil RC&D office, 814-226-8160, ext. 192.

In western Ohio, the Conservation Tillage Conference

The annual Conservation Tillage & Technology Conference (CTC) will be Feb. 22-23 at Ada, Ohio, which is located between Kenton and Lima. This annual conference features 60 speakers and draws over 600 participants. Crop consultants can pick up at least 5 hours of CCA credits in Nutrient Management AND 5 hours in Soil & Water, plus other categories.

Among the featured topic areas are: corn after corn; cover crops; scouting; organic farming on a big scale; drill adjustment; precision farming; ag technologies; and managing manure. Among the speakers from outside Ohio are Jill Clapperton, Tony Vyn, Ron Gehl, Pete Kleinman, Steve Groff, Scott Shearer, and Dan Towery. Farmers on the program include: Tom Besecker, Keith Kemp, David Brandt, Ron Rosman and Jim Van Tilburg. About 20 OSU personnel are also presenting.

Early registration is $30 per day, or $50 for both days. After Feb. 16 add $10. The full program and details are on the web site: http://ctc.osu.edu. Or call 419-422-3851 for program and CCA information. For questions about registration call 419-223-0040, then press 3.

From the Agronomic Crops Team Calendar

Authors: Harold Watters

See below but you may also check our website to keep aware of upcoming regional events: https://agcrops.osu.edu/calendar/.

Precision Agriculture Data Management, Analysis and Decision Making Workshop (A three day hands-on computer lab based workshop series held 1/16, 1/23 and 1/30)
Time: 9:00 a.m.
County of Meeting Location: Knox
Location: Knox County Ag Center
Address: 1025 Harcourt Road, Mt Vernon, 43050
Cost: $80 for first participant from a farm and $60 for each additional with a registration limitation of 19 farms.
For more information:More Information or John Barker at barker.41@osu.edu or 740-397-0401

Northern Ohio Crop Day - February 8th
Time: 9:00 a.m.-3 p.m.
County of Meeting Location: Sandusky
Location: Old Zim's Wagon Shed
Address: 1375 N State Route 590, Gibsonburg
Cost: $15 plus PAT credits
CCA Credits: applied for
PAT Credits: Private (CORE, 1, 8, 12) Commercial (CORE, 2a, 2d, 9)
For more information: Mark Koenig at koenig.55@osu.edu or 419-334-6340.

Error in the 2006 Ohio Soybean Performance Trial Data

Authors: Jim Beuerlein

The Phytophthora gene designation and the partial resistance score for some varieties in the 2006 Ohio Soybean Performance Trials were incorrect due to a data sorting error. The correct data was placed on the internet at: http://www.oardc.ohio-state.edu/soy2006/ and is also available on the Agronomic Crops Team webpage under Soybean Crop Info at https://agcrops.osu.edu after 5:00 PM on January 17, 2007.

Archive Issue Contributors: 

Peter Thomison, Rich Minyo and Allen Geyer (Corn Production), Anne Dorrance, Pierce Paul, and Dennis Mills (Plant Pathology), Robert Mullen (Soil Fertility), Ron Hammond and Bruce Eisley (Entomology), Randall Reeder (Ag Engineering), Jim Beuerlein (Soybean Production) and Mark Loux (Weed Science). Extension Agents: Ed Lentz (Seneca), Glen Arnold (Putnam), Keith Diedrick (Wayne), Jonah Johnson (Clark), Harold Watters (Champaign) and Greg LaBarge (Fulton).

Crop Observation and Recommendation Network

C.O.R.N. Newsletter is a summary of crop observations, related information, and appropriate recommendations for Ohio crop producers and industry. C.O.R.N. Newsletter is produced by the Ohio State University Extension Agronomy Team, state specialists at The Ohio State University and the Ohio Agricultural Research and Development Center (OARDC). C.O.R.N. Newsletter questions are directed to Extension and OARDC state specialists and associates at Ohio State.