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Stratification And Light Improve Germination Of Katsura Tree Seed, Michael S. Dosmann, Jeffery K. Iles, Mark P. Widrlechner Dec 1999

Stratification And Light Improve Germination Of Katsura Tree Seed, Michael S. Dosmann, Jeffery K. Iles, Mark P. Widrlechner

NCRPIS Publications and Papers

Germinability of two, half-sib seed sources of Cercidiphyllum japonicum Sieb. & Zucc. and one seed source of Cercidiphyllum magnificum (Nakai) Nakai was determined after not stratifying or stratifying seeds at 3.5 ± 0.5 °C (38.3 ± 0.9 °F) for 8 days followed by germination for 21 days at 25 °C (77 °F) in darkness or under a 15-hour photoperiod. Stratification was not required for germination, but increased germination percentage, peak value, and germination value for both species. Stratification increased germination of C. japonicum from 42% to 75%, and germination of C. magnificum from 12% to 24%. Light enhanced germination ...


1999 Season Review Of Soybean Diseases, X. B. Yang Dec 1999

1999 Season Review Of Soybean Diseases, X. B. Yang

Integrated Crop Management News

The soybean diseases encountered in the 1999 growing season were different from those of the last couple of years. Brown stem rot and white mold were not concerns in 1999, but diseases that favored warmer weather gradually emerged as production problems. In this article, I review the prevalence of soybean diseases that occurred in the 1999 growing season.


New Publication About Corn Insects, Marlin E. Rice Dec 1999

New Publication About Corn Insects, Marlin E. Rice

Integrated Crop Management News

Last month, the Entomological Society of America (ESA) released their newest publication title Handbook of Corn Insects. The handbook is written by 74 entomologists representing universities, federal agencies, and corporations. It is a comprehensive resource and contains the following:

  • detailed descriptions of 76 insect pests of corn and their injury;
  • 158 color photographs, dozens of illustrations, and distribution maps;
  • illustrated keys to help identify pests and corn injury;
  • a section on beneficial insects and insect diseases;
  • strategies for management of corn insects; and
  • glossary of terms.


Corn Diseases In 1999, Gary P. Munkvold Dec 1999

Corn Diseases In 1999, Gary P. Munkvold

Integrated Crop Management News

This year brought some notable disease problems to the corn crop, and it is surprising that the average yield for the state turned out as well as it did. Of course, I spend most of my time in the worst-looking fields so I usually have a pessimistic outlook. Significant disease problems in 1999 included seedling blights, Stewart's disease (Stewart's wilt), rusts, gray leaf spot, and stalk rots.


Improve Your Bid For Crp, Ralph Mayer, Duane Miller, Michael J. Tidman Dec 1999

Improve Your Bid For Crp, Ralph Mayer, Duane Miller, Michael J. Tidman

Integrated Crop Management News

Landowners will be able to sign up for the next round of the Conservation Reserve Program (CRP) between January 18 and February 11, 2000. The CRP is designed to improve natural resources by protecting millions of acres of topsoil from erosion. Landowners participate in CRP by taking crop and grazing land out of production and planting vegetative cover in its place. Planting cover restores habitat for wildlife and improves water quality in streams, ponds, lakes, and rivers.


Alternatives For P And K Management: A Role For Deep Banding And Starter?, Antonio P. Mallarino Dec 1999

Alternatives For P And K Management: A Role For Deep Banding And Starter?, Antonio P. Mallarino

Proceedings of the Integrated Crop Management Conference

Adequate amounts of soil phosphorus (P) and potassium (K) are needed to support sustained corn and soybean production. These requirements have been recognized for a long time, and soil testing is a useful tool to estimate P and K fertilization needs. Obviously, fertilizer applications to low-testing soils increase grain yield and result in economic benefits for crop producers. Continued P and K fertilizer applications increase soil-test P and K values over time, and this is considered a desirable consequence of fertilization when soil test are initially low. However, long-term use of fertilization has increased soil-test P and K levels of ...


Managing Manure Phosphorus, Bahman Eghball, Brian J. Wienhold, John E. Gilley Dec 1999

Managing Manure Phosphorus, Bahman Eghball, Brian J. Wienhold, John E. Gilley

Proceedings of the Integrated Crop Management Conference

Manure, a renewable resource, contains nutrients that are needed for plant growth. Phosphorus in manure can be utilized for crop production as a substitute for synthetic fertilizers. Phosphorus in manure can also be a source of surface or ground water contamination if not used properly. Increased P concentration can lead to eutrophication of surface waters. Management systems need to be developed to utilize manure P effectively without adverse effects on the environment.


Spatial Weed Distribution: Can It Be Used To Improve Weed Management, Bob Hartzler Dec 1999

Spatial Weed Distribution: Can It Be Used To Improve Weed Management, Bob Hartzler

Proceedings of the Integrated Crop Management Conference

Identifying the variability within a field and managing inputs to account for this variability is one of the underlying principles of precision agriculture. Although most agronomists recognize that weed populations within a field usually are highly variable, there has been relatively little effort to incorporate knowledge regarding weed populations into weed management plans. This paper will provide an introduction to the spatial characteristics of weed populations and how we might utilize this information to enhance weed management programs.


The Role Of Bt Hybrids In Stalk Rot Management, Emily W. Gatch, Gary P. Munkvold Dec 1999

The Role Of Bt Hybrids In Stalk Rot Management, Emily W. Gatch, Gary P. Munkvold

Proceedings of the Integrated Crop Management Conference

Genetically modified organisms such as Bt corn, engineered to produce a bacteria-derived toxin targeting the European corn borer, have been readily adopted as pest management tools by producers throughout the US. While Bt hybrids have demonstrated consistent yield benefits during seasons of heavy European corn borer infestation, growing consumer opposition to the use of genetically modified organisms, particularly in European and Asian markets, has both farmers and scientists questioning the future of biotechnology crops. Rather than abandon developments which have the potential to deliver more effective and environmentally sound management options, a greater effort must be made on the behalf ...


Emergence Patterns Of Annual Weeds Of Corn And Soybean, Douglas D. Buhler, Robert G. Hartzler, Lowell D. Sandell Dec 1999

Emergence Patterns Of Annual Weeds Of Corn And Soybean, Douglas D. Buhler, Robert G. Hartzler, Lowell D. Sandell

Proceedings of the Integrated Crop Management Conference

A better understanding of weed biology is critical for the development of more efficient weed management systems. Improved information on weed biology will not allow us to eliminate the inputs currently used to manage weeds. However, it provides the foundation for the development of new strategies and more efficient techniques to use these tools, resulting in more reliable weed management systems that are cost-effective and pose less threat to the environment.


Weed Management Update For The Next Millenium, Micheal D. K. Owen Dec 1999

Weed Management Update For The Next Millenium, Micheal D. K. Owen

Proceedings of the Integrated Crop Management Conference

In general, the 1999 growing season was excellent with regard to weed management. Weather patterns provided frequent rain thus enhancing soil-applied herbicide performance. While these rains also made timely postemergence applications a challenge, the efficacy of herbicides was quite good and larger weeds were consistently controlled. On the down side, these same weather conditions also reduced crop tolerance to herbicides, favored multiple and delayed weed emergence, and caused difficulties for mechanical weed management strategies. Regardless, 1999 was a successful cropping season.


Integrated Crop Management Services Selling Advice For Profit, Susan Brown, Dan Frieberg, Joel Dejong, Paul Kassel, Kevin Kuhn Dec 1999

Integrated Crop Management Services Selling Advice For Profit, Susan Brown, Dan Frieberg, Joel Dejong, Paul Kassel, Kevin Kuhn

Proceedings of the Integrated Crop Management Conference

Some progressive Iowa dealers are developing comprehensive, fee-based integrated crop management (ICM) services that increase profitability for their own businesses as well as for their customers' operations. More commonly, dealers provide crop management services free in support of product sales, but these services are limited in scope and generally involve diagnosing and reacting to problems. In contrast, the principal focus of fee-based ICM services is on field-by-field planning from a systems perspective (Brown et al, 1995). ICM aims to manage (avoid or control) nutrient and pest problems, if possible, not just rescue the crop once a problem has occurred. ICM ...


Variability Of Soil And Landscape Properties Related To Precision Agriculture, Thomas E. Fenton Dec 1999

Variability Of Soil And Landscape Properties Related To Precision Agriculture, Thomas E. Fenton

Proceedings of the Integrated Crop Management Conference

Soil survey involves the mapping, classification, correlation, and interpretation of soils. The first soil survey in Iowa was in the Dubuque County area but did not include the entire county. The field work was done in 1902 and the report was published in 1903. Since that time, most Iowa counties have had at least two soil surveys completed and some have had three. The basic factors of soil formation have not changed but the use of the soils for intensive agriculture has resulted in changes in some soil properties, especially of the surface horizons. However, generally factors other than soil ...


Biology And Management Of Corn Anthracnose, Gary C. Bergstrom Dec 1999

Biology And Management Of Corn Anthracnose, Gary C. Bergstrom

Proceedings of the Integrated Crop Management Conference

The fungus Colletotrichum graminicola causes corn anthracnose, a damaging disease in the U.S. Corn Belt and many other locations in the world where corn is grown. The anthracnose syndrome encompasses fungal attack of most corn tissues throughout the plant's development. Anthracnose leaf blight (ALB) and anthracnose stalk rot (ASR) are of particular concern because of their effects on corn yield. Estimated grain yield losses due to anthracnose range from zero to 40%, depending on hybrid, environment, timing of infection, and other stresses. Anthracnose is a not a new disease, having been documented in North America since 1855. It ...


Fertilization To Rescue Corn Crops Following Losses Of Fall Nitrogen, Jason Ellsworth, Kip Balkcom, Alfred M. Blackmer Dec 1999

Fertilization To Rescue Corn Crops Following Losses Of Fall Nitrogen, Jason Ellsworth, Kip Balkcom, Alfred M. Blackmer

Proceedings of the Integrated Crop Management Conference

Nitrogen fertilizer recommendations in the past focused more on rates of application than on methods and times of application. Old rules of thumb based on yield goals and credits, for example, made no distinction between optimal rates when N was applied in the fall and optimal rates when N was applied in May. Such recommendations essentially ignored evidence that spring rainfall can cause substantial losses of fall-applied N. Losses of N were easy to ignore because they were not readily detectable.


Biology And Management Of Soybean Diseases Increasing In Importance To Iowa Soybean Production, X. B. Yang Dec 1999

Biology And Management Of Soybean Diseases Increasing In Importance To Iowa Soybean Production, X. B. Yang

Proceedings of the Integrated Crop Management Conference

Different plant pathogens have different environmental requirements for growth and survival. As the weather changes from season to season, so does the prevalence of certain pathogens. This natural cycle results in a changing disease picture in production systems and poses a challenge for soybean producers. Changes in farming technology, farming practices, soybean germplasm, and climate often are followed by changes in plant diseases. In the last ten years, growers in Iowa as well as rest of the north-central region of the U.S. have witnessed dramatic changes in soybean diseases including observed epidemics of some new or re-emerging diseases. For ...


Occurrence And Impact Of Corn Diseases In 1999, Gary P. Munkvold Dec 1999

Occurrence And Impact Of Corn Diseases In 1999, Gary P. Munkvold

Proceedings of the Integrated Crop Management Conference

This year brought us a few surprising and a few not-so-surprising disease episodes. We have had two consecutive years of very mild winters, which is nice in January, but it can come back to haunt us in May. Although the endemic pathogens of this part of the country are adapted to cold winters, survival of some of them can be enhanced by mild winter weather. Some pathogens that are more sensitive to cold may not be much of a problem here, but they can become a problem if weather is consistently mild. This year it was evident that the mild ...


The Pesticide Decision Tool: A Field-Level Approach To Integrating Envionmental Factors In Pesticide Decision Making, John Vickery Dec 1999

The Pesticide Decision Tool: A Field-Level Approach To Integrating Envionmental Factors In Pesticide Decision Making, John Vickery

Proceedings of the Integrated Crop Management Conference

The Institute for Agriculture and Trade Policy (IATP) is working to reduce the environmental impacts of agriculture and improve water quality through the voluntary adoption of on-farm assessment and decision tools. The objective of the Pesticide Decision Tool (PDT) project is to facilitate the integration of environmental risk assessment in the selection and management of pesticides in arable crop production. It is designed for use by agricultural professional such as co-op and elevator agronomists, independent crop consultants, and Natural Resources Conservation Service (NRCS), Soil and Water Conservation District, and university Extension specialists, as well as by farmers. We take a ...


Soil Phosphorus Testing For Crop Production And Environmental Purposes, Antonio Mallarino Dec 1999

Soil Phosphorus Testing For Crop Production And Environmental Purposes, Antonio Mallarino

Proceedings of the Integrated Crop Management Conference

Increasing animal production in the state or its concentration in certain areas is increasing the amounts of manure being applied to the land. Often, the manure is applied at rates or at a frequency that exceed the phosphorus (P) needs of crops and even the amount removed in harvested products. Animal manure can supply the nitrogen (N) and P needed by crops as well as other nutrients. Due to its relative N and P content and potential N losses, however, continued use of rates that supply the N removed in com grain (and in soybean grain too) results in P ...


Sprayer Nozzle Selection For Pesticide Performance And Drift Reduction, Brent A. Pringnitz Dec 1999

Sprayer Nozzle Selection For Pesticide Performance And Drift Reduction, Brent A. Pringnitz

Proceedings of the Integrated Crop Management Conference

Avoiding excessive spray drift is a key objective for applicators. With increasing acreage planted to herbicide-resistant crops and a shift to more postemergence spraying, the potential for off-target plant damage has increased in recent years. Off-site damage is often readily apparent in adjacent farmland and rural acreages. As increased emphasis is placed on drift-reduction, nozzle manufacturers have responded with new nozzle types designed to lower drift potential and accommodate new application technologies. Precision agriculture and site-specific farming have added additional demands for nozzles than can accommodate a wider pressure operating range.


Genetically Modified Crops: Guidelines For Producers, Neil E. Harl Dec 1999

Genetically Modified Crops: Guidelines For Producers, Neil E. Harl

Proceedings of the Integrated Crop Management Conference

With the consumer resistance to products containing genetically modified ingredients in Europe, Asia and elsewhere rising in recent months, and processors responding to that resistance, the focus is on how producers can protect themselves. It's especially critical for those producing non-GMO varieties.


The Iowa Grain Quality Initiative, Darren Jarboe, Charles Hurburgh Jr. Dec 1999

The Iowa Grain Quality Initiative, Darren Jarboe, Charles Hurburgh Jr.

Proceedings of the Integrated Crop Management Conference

The Iowa Grain Quality Initiative (IGQI) is an interdisciplinary grain quality research and information program. IGQI developed through a common interest from five Iowa organizations to increase the value of Iowa grain. These organizations united in the belief that matching grain quality more closely to specific end users' needs would promote economic growth.


Estimating The Accuracy And Precision Of Nitrogen Management During Corn Production, Kip Balkcom, Alfred M. Blackmer, Nanchang Yang Dec 1999

Estimating The Accuracy And Precision Of Nitrogen Management During Corn Production, Kip Balkcom, Alfred M. Blackmer, Nanchang Yang

Proceedings of the Integrated Crop Management Conference

The advent of variable-rate fertilizer applicators has created a need for fertilizer N recommendations that address spatial variability within cornfields. These recommendations must include assessments of where variable-rate applications are likely to be profitable and where they are not. They also must indicate how rates should vary with soil type within fields when variable-rate applications are used.


Highlights Of The 1999 Growing Season, Dale E. Farnham Dec 1999

Highlights Of The 1999 Growing Season, Dale E. Farnham

Proceedings of the Integrated Crop Management Conference

Frequently I am asked, "how does this growing season compare to previous years?" In reality, there are certain generalizations that can be drawn regarding the similarities among all growing seasons. Rainfall, temperatures, weeds, insects, diseases, frost, all seem to have some degree of impact on every growing season. As I review the conditions of the 1999 growing season, there are many similarities to what was experienced in the 1998 growing season. Too cool, too wet, too warm, too dry, high winds, early frost ... all played significant roles in influencing the 1999 crop. However, given all the adverse conditions that occurred ...


Manure Educational Programs In Iowa: Current Programs And Future Needs, Jim Johnson, Angela Rieck-Hinz, Gerald Miller Dec 1999

Manure Educational Programs In Iowa: Current Programs And Future Needs, Jim Johnson, Angela Rieck-Hinz, Gerald Miller

Proceedings of the Integrated Crop Management Conference

Manure management is an important topic in Iowa. Recent legislation in Iowa has created a need to provide livestock and crop producers with continued educational programs regarding manure nutrient management. Federal strategy proposed by the USDA and EPA have reaffirmed the need for educational programs and provide an opportunity to lay groundwork for mandatory as well as voluntary nutrient management efforts. Iowa State University's (ISU) objective is to provide voluntary educational programs for manure nutrient management and train producers to meet the requirements of State laws. This will position producers to continue the educational process to meet Federal requirements.


Targeting The Premium Market: Organic Crops For Iowa, K. Delate, James Boes, Robert Turnball Dec 1999

Targeting The Premium Market: Organic Crops For Iowa, K. Delate, James Boes, Robert Turnball

Proceedings of the Integrated Crop Management Conference

According to the USDA Economic Research Service, statistics on organic production in the U.S. lag far behind those complied for conventional agriculture. In the last USDA census in 1995, there were 4,050 organic farmers reporting 1.5 million acres of production (Greene 1999). The Organic Farming Research Foundation estimates that there were 10,000 U.S. organic farmers in 1998. In Iowa, 120,000 acres of organic production were reported to the Iowa Department of Agriculture and Land Stewardship (IDALS 1999). This figure reflects only acreage reported by those farmers who returned their survey; thus, more acres are ...


What Does The Late-Spring Soil Test Really Measure?, Alfred M. Blackmer, Nanchang Yang, David Hansen Dec 1999

What Does The Late-Spring Soil Test Really Measure?, Alfred M. Blackmer, Nanchang Yang, David Hansen

Proceedings of the Integrated Crop Management Conference

The late-spring test for soil nitrate has been available in Iowa for about 10 years. Guidelines for using this test clearly indicate that the test measures concentrations of nitrate in the surface foot of soil when corn plants are 6 to 12 inches tall. Ongoing discussions concerning the reliability of the soil test, however, indicate uncertainty in what should be concluded from the soil nitrate concentrations measured.


Managing Phosphorus: Agronomic And Environmental Concerns, Regis Voss Dec 1999

Managing Phosphorus: Agronomic And Environmental Concerns, Regis Voss

Proceedings of the Integrated Crop Management Conference

Phosphorus (P) is an essential nutrient for terrestrial and aquatic plants. We recognize the beneficial effects of P on the growth and yields of beneficial crops. There is increasing concern and attention being given to phosphorus losses from agricultural soils. Substantial amounts of P entering surface waters (lakes, other surface impoundments and streams) contribute to accelerated eutrophication of lakes and reservoirs. Eutrophication is a process by which a water body becomes rich in dissolved nutrients and, often, seasonably deficient in oxygen. Eutrophication due to excessive algal and other plant growth and their ultimate decomposition, which consumes oxygen, limits the use ...


Making Every Fertilizer Dollar Pay, John E. Sawyer Dec 1999

Making Every Fertilizer Dollar Pay, John E. Sawyer

Proceedings of the Integrated Crop Management Conference

In an ideal crop production system, all nutrient and limestone needs would be determined by evaluating expected return from each input, without required purchases being limited by overall financial resources. More realistically, resources get allocated by priority need, and decisions related to fertilizer and limestone use are judged against other crop production needs, enterprise requirements, and overall farm business goals. This allocation becomes especially pertinent when cash flow is low and financial resources become inadequate. In this situation, and considering all potential inputs, the focus should be on garnering the greatest return to each input dollar expended. Prioritizing fertilizer and ...


Soybean Cyst Nematode - Biology And Management, Gregory L. Tylka Dec 1999

Soybean Cyst Nematode - Biology And Management, Gregory L. Tylka

Proceedings of the Integrated Crop Management Conference

Soybean cyst nematode, Heterodera glycines, is a microscopic, unsegmented plant-parasitic roundworm that attacks the roots of soybeans. Many plant-parasitic nematodes are believed to be native to the United States, but soybean cyst nematode likely was introduced into the United States from Japan. Soybean cyst nematode was first discovered in the United States in 1954 in North Carolina (Winstead et al., 1955) and since has spread to 26 additional states in the Southeast and Midwest (Figure 1) (Noel, 1992). The nematode was first discovered in Iowa in Winnebago County in 1978. Currently, soybean cyst nematode is known to exist in 90 ...