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2/7/2011 - 2/13/2011

Southern Iowa Biomass Crop Workshop March 17

By Emily Heaton, Department of Agronomy and Brent Pringnitz, Corn Soybean Initiative

The Southern Iowa Resource Conservation and Development Area has been working with Iowa State University and the Iowa Farm Energy Working Group to evaluate biomass crops, including giant miscanthus and warm season grasses that can be used to produce renewable energy feedstocks. Two companies are cooperating in this joint venture, with plans to create businesses that convert biomass to anhydrous ammonia and energy pellets.

Collectively, these renewable energy enterprises would consume 54,000 acres of energy crops and create over 50 new jobs. Project cooperators are sponsoring a workshop where farmers will learn about opportunities to grow and market profitable biomass crops that are adapted to southern Iowa soils and climate.

The Biomass Crop Production Workshop will be held Thursday, March 17, at Southwestern Community College in Creston, Iowa. Registration opens at 7:30 a.m., the program starts at 8:15 a.m. and concludes at 3 p.m. Workshop participants will also learn about a new USDA initiative called the Biomass Crop Assistance Program. The initiative provides cost share incentives for producers to establish, grow and harvest energy crops.

The workshop morning session will focus on using perennial grasses, such as miscanthus, and other biomass crops for energy production. Iowa State University specialists will focus on species selection, agronomics and the best fit in southern Iowa agricultural systems. Representatives from ShowMe Energy and SynGest will discuss using perennial grasses as homegrown energy, markets and industry demand. The afternoon program features topics on fuels and chemicals from biomass as well as federal support for bioenergy programs.

Registration can be completed online with a credit card (MasterCard or VISA only) at Registrations also may be faxed with a credit card to 515- 294-1311 or be mailed along with a check or credit card information to: ISU Agribusiness Education Program, 2104B Agronomy Hall, Ames, IA, 50011-1010.  Pre-registration is $20 until midnight, March 11. After that date registration is $30. Registrations will be accepted the day of the workshop. Registration includes refreshments, lunch and class materials. For more information, call 515-294-6429 or email

This program is sponsored by ISU Extension, Southern Iowa Resource Conservation and Development Area, South Central Iowa Soil and Water Conservation Districts, and SynGest.



Emily Heaton is an Iowa State University agronomy professor with extension responsibilities in biomass production. She can be contacted by emailing or calling 515-294-1310. Brent Pringnitz is an extension program specialist with ISU’s Corn and Soybean Initiative.

New Combination Crop Insurance Workshops Scheduled

By William Edwards, Department of Economics

The old multiple peril crop insurance policies have been replaced by a single policy with several options. Iowa State University Extension will hold workshops to explain the new combination policy. William Edwards, ISU Extension economist, and ISU farm management field specialists, will discuss the new crop insurance policy and options.

Other workshop topics will include the proposed good performance premium refund, basic and enterprise units, and grain marketing considerations. Computer applications will be available to help participants analyze their own farming operations.

Workshops are scheduled at five locations :

Feb. 15 – Cherokee – Cherokee County Extension Office – 10 a.m.- 2 p.m.
Feb. 21 – Atlantic – Cass County Community Center – 10 a.m.- 2 p.m.
Feb. 22 – Fairfield – Jefferson County Extension Office – 12-4 p.m.
Feb. 24 – Iowa Falls – Ellsworth Community College (hosted by Hardin County Extension) 10 a.m. to 2 p.m.
March 1 – Washington – Washington County Extension Office – 1-4 p.m.

Workshop registration is $20 and includes lunch. To register, call the county extension office hosting the event – Cherokee, 712-225-6196; Atlantic, 877-596-7243; Fairfield, 641-472-4166; Iowa Falls, 888-648-5005; Washington, 319-653-4811. Registration is limited to 30 people per site.


William Edwards is a professor of economics with extension responsibilities in farm business management. Edwards can be contacted at (515) 294-6161 or by emailing

Waterhemp Wins Again

By Bob Hartzler, Department of Agronomy

Waterhemp caused significant economic losses for many Iowa growers during the mid-1990s.  With the introduction of new technologies, primarily Roundup Ready soybeans, most farmers have minimized the economic impact of waterhemp in corn and soybean production. However, the selection of herbicide resistant waterhemp biotypes (Table 1) threatens to return us to an era where uncontrolled waterhemp causes significant yield losses across the Corn Belt. 

The first appearance of resistance to the HPPD inhibitors was reported in 2009 in waterhemp found in two fields in Iowa and Illinois. Several factors contributed to this appearance.

The two fields where HPPD resistance evolved are approximately 140 miles apart, but they have several similarities in management practices. The Illinois field was maintained in continuous corn since at least 2003, whereas the Iowa field was a corn-soybean rotation.  However, both fields were used for seed corn production during the period of HPPD use. The specific herbicide programs of the fields are provided in Tables 2 and 3.

A cursory evaluation of the weed management programs for the two fields suggests the growers took a reasonable approach to managing waterhemp. Preemergence herbicides were used in all years, a benefit since the specific herbicides have activity on waterhemp. In most years, atrazine was tank-mixed with Callisto, a combination with synergistic activity on susceptible weeds. The herbicide programs resulted in waterhemp being exposed to three herbicide groups (5, 15 and 27) each year of corn production. In soybean, two herbicide groups (4 and 9) with activity on waterhemp were used. Exposing weeds to multiple herbicide groups is the key to resistance management, so what went wrong in these fields?

Several factors likely contributed to evolution of HPPD resistance in these two fields.

• The first is the production of seed corn. Corn inbreds are much less competitive with weeds than hybrid corn due to the smaller canopy of inbreds, thus seed corn production relies much more on herbicides than field corn production.

• A second factor is that the waterhemp in both fields was already resistant to atrazine, thus the inclusion of group 5 herbicides provided no benefit in terms of managing waterhemp. 

• Thirdly, although the rates of the preemergence herbicides were not described in the publications, it is likely that below average rates of both preemergence herbicides (Dual II Magnum and Prowl) were used due to the lower tolerance of corn inbreds to herbicides than field corn.  

• Finally, at the first sign of waterhemp control failures the HPPD inhibitors remained the primary tool to manage waterhemp. Sequential applications of HPPD products were used in Illinois in 2008 and 2009, and in 2007 in Iowa, likely due to waterhemp surviving the initial treatment.

What should be learned from the evolution of HPPD resistance in these two fields?

Over the last decade weed scientists have focused on risks associated with our heavy reliance on glyphosate, but these two cases should remind us that all herbicides are at risk of resistance. 

Resistance was confirmed after only five years of HPPD use in Iowa and seven years in Illinois, but the need for ‘rescue’ treatments in 2007 in Iowa and 2008 Illinois suggests the problem was present sooner. This shows how rapidly resistant biotypes can be selected from a weed population. 

In today’s production systems, herbicides and the crop canopy are the primary tools used to manage weeds. Cultural practices that enhance the crop’s competitiveness should be adopted in order to help suppress weed populations. To protect the value of herbicides, weed management programs must be implemented that include multiple herbicide groups having significant activity on the important weeds found in the field. There is natural reluctance to this approach because, who wants to pay to kill a weed twice? These two case studies show that managing herbicide resistance is not as simple as counting the number of herbicide groups used, but that the contribution of each herbicide in controlling individual weeds must be considered. 


Hausman, N.E., S. Singh, P.J. Tranel, D.E. Riechers, S.S. Kaundun, N. D. Polge, D.A. Thomas and A. G. Hager. 2011.  Resistance to HPPD-inhibiting herbicides in a population of waterhemp (Amaranthus tuberculatus) from Illinois, United States.  Pest Manage. Sci. 67: In press.

McMullan, P.M. and J.M. Green.  2010.  Identification of a tall waterhemp (Amaranthus tuberculatus) biotype resistant to 4-HPPD inhibiting herbicides and atrazine in Iowa.  Proc. NCWSS 65:125.


Bob Hartzler is an Iowa State University professor of agronomy with extension, teaching and research responsibilities.

Help Sessions Offered for Commercial Pesticide Applicator Test

By Jim Fawcett, ISU Extension field agronomist

All commercial pesticide applicators must take exams in order to become certified initially; some applicators choose to become re-certified by exam rather than by attending continuing instructional courses. With the increased interest in applying fungicides on corn and soybeans some applicators are interested in adding agricultural diseases (category 1C) to their current certification.

Two training sessions designed to help prepare individuals for the commercial pesticide applicator examinations will be offered in southeast Iowa. One session is scheduled for Wednesday, Feb. 23 at the Linn County Extension Office at 3279 7th Avenue, Marion, Iowa. A second session will be offered in Bettendorf on Tuesday, March 8 at the Scott County Extension Office, 875 Tanglefoot Lane. Both sessions run from 9 a.m. to approximately 1 p.m.

The training sessions will cover the Iowa Core Manual and categories 1A (Agricultural Weed Management), 1B (Agricultural Insect Control), 1C (Agricultural Crop Disease Management), 3O, T and G (Ornamental, Turf, and Greenhouse Pest Management), 4 (Seed Treatment) and 6 (Right-of-Way). Training on the Iowa Core Manual will be given for the first 1.5 hours, with the training on the other categories following.

There is a $25 fee per person at each training session. These training sessions do NOT qualify as continuing instructional courses. For more information, please contact Jim Fawcett at 319-337-2145, Patrick O’Malley at 319-337-2145, or Virgil Schmitt at 563-263-5701.


Jim Fawcett is an Iowa State University Extension field crops specialist serving eastern Iowa.

This article was published originally on 2/14/2011 The information contained within the article may or may not be up to date depending on when you are accessing the information.

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