Vol. 18, No. 18, February 6, 2004

Last issue this season

Rebecca Lamb, Asst. Editor and Joy Landis, Editor

This is officially the last issue of the Field Crop CAT Alert for the 2003 season. Thank you for being a part of the newsletter this year, and we hope that our services will continue to help you throughout 2004.

At http://www.ipm.msu.edu/CAT03_fld/pdf/fc03index.pdf you will find the index for the 2003 season. It should help you find articles on specific topics from this past year.

Our new season will begin on March 18, and we look forward to another year providing pest management advice for our readers!

How to select a corn hybrid

Kurt Thelen
Crop & Soil Sciences

Selecting the right corn hybrid may be the most critical step in planning for your 2004 crop in terms of potential profitability. Table 1 shows a summary of results from the 2003 MSU corn hybrid testing program. Note the large differences between the best and worst hybrids. These results are very typical with what we see each year in terms of the magnitude of difference between the best and worst yielding hybrids in a particular maturity zone. In general terms, all the hybrids entered into the testing program are considered "good" hybrids by their respective companies or they would not enter them in the trial in the first place. Hybrids vary significantly in their ability to adapt to particular environmental conditions. The key to selecting the right hybrid, one that will give you the extra 30, 50, or even 60 bushels per acre, lies in selecting the right genetics for your particular farm. Following is a suggested system for selecting corn hybrids:

1)    Using the MSU variety trial results, select the top 20 yielding varieties from the maturity zone nearest your farm.
2)    Identify other performance characteristics important for your farm and evaluate these 20 accordingly, eliminating those that have traits you are not interested in.
3)    Look for other sources of data/information on these remaining hybrids. Other sources include data from other state testing programs and seed companies. Eliminate those hybrids that are not consistent performers.
4)    Obtain a unit or two of seed to evaluate the several remaining varieties on test strips on your own farm.
5)    Incorporate the top performing varieties from these test strips into your rotation.

Because the average life span of a modern corn hybrid is only around three years, the above process must be repeated annually. It may be bothersome to follow, but the payoff can be tremendous in selecting the right genetics for your particular farm conditions. Some other things to consider when evaluating hybrid yield data include:

§      One-year results are less reliable than two- or three-year averages and should be interpreted with more caution.
§      The "least significant difference" (lsd) value on the bottom of hybrid performance tables indicates the difference in bushels per acre required to confidently evaluate and distinguish hybrid performance.
§      There's no substitute for observing individual characteristics while a hybrid is growing - take advantage of demonstration plantings at test locations.
§      Weather conditions can significantly impact the way a given hybrid performs during a particular year - be sure to read up on the local growing conditions when interpreting yield data.

Michigan State University is testing out a new interactive database for the corn hybrid and soybean variety performance trials. The goal of this proto-type program is to provide growers with a tool for evaluating yield trial results. This program is web-based and can be accessed at http://www.css.msu.edu/varietytrials/research/Index.cfm

Table 1. Summary of 2003 MSU hybrid testing performance trials for each maturity zone. Deviation reflects the difference between the highest and lowest yielding hybrid for each respective trial. Results are given as bushels per acre.

Begin planning your nitrogen applications now

Carrie Laboski
Crop & Soil Sciences

Even though the ground is still frozen and snow covered, now is the time to start thinking about nitrogen (N) applications. Last season's dry weather may impact the soil's ability to supply N this year. Where dry weather resulted in poor legume crops (e.g. soybean), N fixation may have been reduced, and the subsequent legume N credit may not be as large as normal. On the other hand, all of the N applied to last year's crop may not have been used and may still be in the soil this spring. A good way to assess how much N may or may not be available to your crops this season is to use a soil nitrate test.

In 2002 and 2003, I conducted a study with the county MSU Extension agents to assess how well the pre-sidedress nitrate test (PSNT) does in reducing N rates and maximizing yield. Locations representing various soil types, crop rotations, manure history, and microclimate were selected by county Extension agents. Several N rates, 0 to 200 or 250 lb N/a, were applied to small plots or field strips and replicated. One-foot soil samples were taken prior to sidedressing when the corn was 6 to 12 inches tall. Yield was measured. Data was analyzed based on economics, using $2.00/bu corn and $0.20/lb N. It must be remembered that fertilizing for maximum yield is not the most economical. This is because of the law of diminishing returns - as maximum yield is approached, it takes more nitrogen (or any nutrient) to increase yield one bushel and the increase in yield does not offset the cost of N.

The results of this research are provided in Table 1. At each site the economic optimum N rate was calculated, and the yield at that N rate was determined (economic optimum yield). Using the economic optimum yield, the base N rate was calculated. This assumes that in the beginning of the season we knew what the economic optimum yield would be and used that as our yield goal in the calculation of the base N rate: Base N rate = (1.36 x yield goal) - 27. The PSNT adjusted N rate was calculated as the Base N rate minus the PSNT credit. The PSNT credit is calculated as: ppm of N in a one-foot sample x 6. The final column is an assessment of how well the PSNT did at adjusting N rates. In this column, the economic optimum N rate is subtracted from the PSNT adjusted N rate. The PSNT was considered to be successful at predicting the optimum N rate if the PSNT adjusted N rate was within plus or minus 30 lb N/a of the economic optimum N rate. Locations where the PSNT was successful are bold and italicized in the right hand column. Forty-six percent of the time, the PSNT adjusted N rate was successful at predicting the economic optimum N rate. This means that 54 percent of the time the PSNT adjusted N rate was unsuccessful. Closer inspection of the results in the right hand column reveal that when the PSNT was unsuccessful, it always over recommended N.

Table 1. Results of N management research in 2002 and 2003.

It is important to note that the economic optimum N rates are relatively low, but that yields for the most part were average or better in most of the study fields. Even though rainfall was less than average at many locations, moisture stress apparently did not impact yield much. The low economic optimum N rates across the state suggest that growers who applied more than 150 lb N/a to corn last year may have residual N in the soil this spring that was not used by last year's crop. At some locations, the amount of N (nitrate + ammonium) remaining in the two-foot soil profile was measured (Table 2). You can see that as last year's N rate increased, the amount of N remaining in the soil profile increased. Barry County was an exception with the opposite trend occurring. At Oceola, last year's corn crop was preceded by five years of alfalfa. The large amount of N remaining in the soil, even when no N was applied, is likely caused by a large contribution of N from the alfalfa. So, if you plan to plant corn this year on ground that was corn last year, you should consider taking a PSNT sample to determine how much N may be left over from last year's crop.

Table 2. Amount of N remaining in the two-foot soil profile last fall from various sidedress N application rates.

The PSNT is a very cost effective tool for reducing N rates. Table 3 highlights the amount of money that could be saved by using the PSNT to reduce N rates. When averaging the PSNT credit over the past two years for all locations in this study, an economic gain of approximately $12/a could have been realized. The range in economic gain was $4.70/a to $36.31/a. An added benefit to using the PSNT is that for every pound of N that you don't apply, and which the crop doesn't need, that's an extra pound of N that is not going to cause water or air quality problems.

Table 3. The value of using the PSNT.

* Assuming that N costs $0.29/lb N in the form of urea.
**Economic gain equals the cost savings on N minus the cost of sampling and analysis if a consultant were hired to sample. Assuming the consultant costs $4/a.

If you are interested in trying the PSNT for the first time and would like more guidance, contact your county Extension agent or Groundwater Stewardship Technician for more information. Also, remember that adjusting sidedress N rates with the PSNT is best done when less than 40 lb N/a is applied at or prior to planting. This study was supported by the Michigan Agricultural Experiment Station and the Groundwater Stewardship Program at the Michigan Department of Agriculture.

New corn and soy processing technology will benefit manufacturing industry

Joy Landis and Rebecca Lamb
MSU IPM Program

Editor's note: Project GREEEN is a research and outreach project designed to rapidly respond to priorities identified by Michigan's plant agriculture industries. Each commodity group idendifies the time-sensitive priorities, and researchers draft their proposals from there. There are four program areas in Project GREEEN that include basic research, applied research, value-added research, and Extension/education/demonstration. In 2003 nearly $1.1 million was awarded to 36 new research projects, and almost $900,000 was appropriated to continuing projects. For more information on Project GREEEN, visit the website at: www.greeen.msu.edu The following project is one of several in 2003 that impacts field crop production.

Michigan wins on multiple economic and environmental levels with a new technology developed by MSU researchers that uses agricultural resources to produce biobased materials for the manufacturing industry. In work funded by Project GREEEN, researchers have developed a new generation of ecofriendly structural materials of significant commercial value from soybean oil and cellulose fibers from corn stover.

"There are plastic products on the market made from soy oil such as plastic bags and picnic utensils. The key to our work is the combination of reinforcing cellulose fibers from corn with plastic made from soy," says Lawrence Drzal, MSU distinguished professor of chemical engineering and materials science and director of the Composite Materials and Structures Center.

"The traditional process of adding glass fibers as reinforcement to petroleum-based plastics is expensive and energy intensive, so we've created a process that extracts fibers from corn stover, which is often left in the field," he explains "The resulting material is energy efficient and less expensive. The cost of glass fiber is almost four times that of the cellulose biofiber, making these new biobased materials less expensive."

Biocomposites made entirely from plant and agricultural products have been shown to be almost as structurally strong as glass-reinforced composite materials. Products that could be manufactured from these biobased composite materials range from construction materials such as deck boards and ceiling tiles to interior component parts of automobiles. MSU has applied for a patent for the process and will license the technology to a manufacturing company.

"The potential market for these materials is about 3 billion pounds per year and growing every year," Drzal says.

 For Michigan farmers, the new process creates value-added opportunities beyond food products. The technology developed by the research team is applicable to various types of natural oils such as those from corn, cottonseed, peanuts and even animals. The diversity of options benefits farmers and the state's economy.

Researchers intend to explore more alternatives for bioproducts.

"The next direction for our research will be to investigate using cellulose fibers derived from native grasses for the structural fiber in composites," Drzal says.

Native grasses are adapted to marginal soil and climate conditions currently underutilized for agriculture. Land unable to support food production could support cultivation of perennial native grasses. Not only could seed and fiber be produced as high value supplemental alternative crops, but additional environmental benefits such as restoring soil structure and reducing pollution may also be possible.

Manure publications available online

Charles Gould
Nutrient Management Agent for
Allegan, Barry, Kent, Muskegon and Ottawa counties

Recently 12 publications entitled Best Environmental Management Practices: Farm Animal Production have been added to the MSU Extension bulletin system and are available on the Internet. This project was a joint effort between faculty and staff at Michigan State University and Purdue University and was funded through a USDA Special Needs grant.

These publications can be accessed on the web in PDF format at:
http://www.ces.purdue.edu/extmedia/ageng.htm#13

The list of titles are as follows:

§      Inspecting Your Confined Feeding Operation (E2823)
§      Emergency Planning for the Farm: Livestock Operations (E2575S)
§      Comprehensive Nutrient Management Plans (E2819)
§      Manure Nutrient Recycling (E2826)
§      Odor Control Options for Confined Feeding Operations (E2828)
§      Building Good Neighbor Relations (E2818)
§      Manure Applicator Calibration (E2825)
§      Land Application of Manure and Environmentally Sensitive Field Characteristics (E2821)
§      Feeding Strategies to Lower N and P in Manure (E2822)
§      Disposal of Farm Medical Wastes (E2829)
§      Land Application Records and Sampling (E2824)
§      Mortality Management (E2827)

Fees increase for applicator certification

Fees for applicator certification in Michigan are increasing. For commercial applicators, the new fee has already increased from $50 to $75. As of October 1, 2003, the fee for private applicators will increase from $10 to $50. In both cases, the certification is valid for three years. This is the first fee increase since 1976, when the law requiring certification was passed in Michigan. - Chris DiFonzo, Pesticide Education

Management strategies, genetics, weed management and fertilizer use will be among the topics of the 2004 Bean and Beet Symposium February 17 in Saginaw, Michigan. The event will run from 8:00 AM to 4:00 PM and will include a trade show and presentations from industry representatives and Michigan State University (MSU) faculty members and Extension specialists.

Sugar beet-related topics will include using oilseed radish for sugar beet cyst nematode control, controlling rhizoctonia crown rot, herbicide tolerance and weed management evaluation, and nitrogen management.

Other sessions will focus on the impact of starter fertilizer on high-phosphorus soil, international bean marketing opportunities and a dry bean production forecast. There is no cost to attend the event. For more information, contact the Saginaw County MSU Extension office at 989-758-2500.

MSU Crop Management and Field Diagnostic School

The 2004 MSU Crop Management and Field Diagnostic School will be held on July 23. This hands-on field day will offer training in entomology, plant pathology, soil science, weed science, and general crop production. More information will be coming as the planning progresses.