Brief Summary of Minutes of Annual Meeting

John Lindquist (chair) welcomed the group and asked Christy Sprague (local host) to provide a general overview of activities for the next two days. Dr. Steve Pueppke (Associate Dean of Research, College of ACES at the University of Illinois) attended as administrative advisor on behalf of Dr. Randy Woodson. Dr. Jim Parochetti (CSREES representative) reiterated the importance of adhering to deadlines and the need to remain focused on a multidisciplinary project. Susan Ratcliffe (NCIPM facilitator) spoke in detail about the NCIPM program.
Election of officers for 2003-04

Chair: Christy Sprague
Secretary: Gregg Johnson

Location of 2004 Summer Annual meeting, Madison, Wisconsin  University of Wisconsin. The meeting date was tentatively set for Monday and Tuesday, July 19-20, 2001.

Objective 1. Understand the basis and relative importance of spatial, temporal, and biological variability in weed/crop competition.

Kathrin Schirmacher (KS) discussed results of field research specifically targeted at objective 1a and 1b. Overall, corn and soybean yield data was variable from year to year. In corn, all four cohorts were established but had problems with lambsquarters and fall panicum establishment. In soybeans, cohort 1 was established but they had problems with cohort 2 and 3. She also talked about their use of dose-response models for analyzing weed competitiveness. Dave Stoltenberg (WI) talked about their results addressing objective 1e. Overall, the range in yield varied between years. However, some general relationships were evident over both years. Lower yield was associated with giant ragweed and velvetleaf. Conversely, higher yield was associated with wild proso millet and large crabgrass. The other four species tested were intermediate, but the order of these species changed from 2001 to 2002. The group talked about ways of integrating this data with WeedSoft. Do we pool data over years and use single indices? This is a concern with very competitive weeds. However, the rank of highly competitive weeds did not change over years. More discussion is needed on this topic. Corey Guza (MI) discussed results from field research in support of sub-objective 1a, 1b, 1e, and 1f. All experiments are in the 3^rd year and are focused on 4 cohort timings across 8 weed species. Corey also reviewed a recent survey of NC-202 members to determine if we had enough data as well as to determine the quality of data. Those involved in research supporting objective 1e and 1f are Michigan, South Dakota, and Wisconsin. Overall, data quality was excellent and there appeared to be enough data to move forward. Most states are following through with their commitments as indicated in the 2002 minutes. Discussion moved to data analysis. Kathrin Shirmacher (KS) and Corey Guza (MI) agreed to analyze the corn data from objective 1a and 1b. Shawn Hock (NE) will be asked to analyze soybean data from objective 1a, 1b, and 1e.

Objective 1c and 1d standard regional protocol (years 3-5):

Michigan, Minnesota, Kansas, Nebraska, and Illinois committed to the protocol outlined in objective 1d for both corn and soybeans in 2004. Wisconsin agreed to establish field studies in support of objective 1c and possibly 1d. John Lindquist will send an e-mail asking for commitments from each state along with protocol information. It was suggested that this group write a paper demonstrating how NC202 data was used to support the development and enhancement of a bioeconomic model, i.e. WeedSoft. Status of lambsquarters competition paper: David Stoltenberg contacted David Fischer two years ago regarding the status of this paper but has not heard any word to date regarding progress. Dave Stoltenberg will contact David Fischer to follow up on the status of this paper. We do not want this paper to slip through the cracks.

Objective 2. Understand spatial, temporal, and biological variability of weed seed in the soil seedbank and it‘s impact on weed/crop competition.

Adam Davis (MI) presented results on weed seed fate in the soil seedbank (objective 2b) based on 2001 and 2002 data. Illinois, Michigan, Minnesota (two sites), Nebraska, Ohio, Washington, and Wisconsin provided data for this study. Overall, weed seed decay was highly variable between sites and years. The group discussed whether to explore the genetic by environment interaction as it relates to these findings. Adam also argued the need to think more about the methodology. The group discussed several ideas related to placement and extraction of weed seed from the soil. The group also discussed the need to consider invasiveness as a function of cropping system as it relates to seed germination and establishment. Michigan and Ohio will continue with the experiment beginning in the fall of 2003. Wisconsin may also participate. Adam Davis (MI) and John Cardina (OH) will discuss protocol and share information with others. Anybody interested can choose to participate at that time. Adam will also take charge of data analysis. Jack Dekker (IA) presented information on FoxPatch, a new model he has developed to forecast weedy foxtail seed behavior in soil seed banks. Drivers in this model are oxygen, water, and temperature. The protocol involves obtaining information on foxtail dormancy state, weather data from time of introduction to emergence, and time of emergence. Jack plans to submit a regional proposal this fall. Anyone interested in participating in this project should contact Jack.

Objective 3. Develop DSS modules to incorporate risk into weed management recommendations.

The WeedSoft bioeconomic model group met with representatives from NC202 this past year. There is strong interest to incorporate NC202 data into WeedSoft. One example is to look at developing a teaching component based on NC202 data. This would allow users to learn concepts using regional data collected by this NC202 group. It was also proposed to incorporate fecundity information based on data collected by Kathrin Schirmacher (KS).

The economist involved in the project (Paul Mitchell, TX) has indicated that he is too busy with other things to be of much help to the NC202 group. It was suggested that we contact David Archer (USDA, Morris MN) as a replacement. Don Wyse (MN) will contact David Archer to determine his level of interest and if he is indeed the right person to work on the project. If we are unsuccessful in this regard, we need to reconsider how we address the risk component of this project. Some members questioned the need to study economic risk and suggested that we focus on biological risk.

Discussion of Future Project Direction and Rewrite

Discussions centered on how best to frame our research questions. It was suggested that bioeconomic models (e.g, WeedSoft) should be the basis for development of appropriate research questions. Some group members felt that we should focus on diverse cropping systems while others suggested the field of invasion biology be incorporated into the development of a new proposal. A number of ideas were talked about during this period. Jim Parochetti (CSREES representative) was asked to provide some guidance regarding new directions and choice of research topic. Jim indicated that the topics discussed thus far are timely and address national issues. Moreover, a change in direction may be viewed favorably. Overall, the group felt strongly that we need to insure that the researchable questions can be addressed using a multi-state approach. John Cardina suggested that we might want to look at a trait-based approach rather than a species-based approach. Measuring traits rather than specific species allow you to get at the reason the system behaves that way it does. The challenge is to decide what traits are important. Phenotypic plasticity is one such trait that was discussed because it oftentimes drives the observed differences in plant growth rate, form, etc However, genotypic traits resulting from outcrossing results in populations with a unique set of traits. For example, what are the determinants in species shifts resulting from changes in tillage, i.e. it is it genotypic variability or phenotypic variability? At this point in the discussion, it was becoming clear that a trait based approach appears to be something we can all get excited about. Continued talks focused on possible traits that we would deem important. Those include:

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Emergence patterns. For example, what is the variability of this trait and how does this influence the ability of weed species to adapt to different systems? What drives the expression of variability?

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Characteristics associated with seed rain.

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GxE interaction in emergence. An example of this would be to establish a common nursery in all states where we could be determine the influence of starting state of seeds vs. the environmental signal at different locations.

It was suggested that we consider organizing objectives of the new project by the life history stage. A second objective would focus on trait assessment beginning at emergence (phase II of life history). Another idea was to establish a wide variety of weeds in different cropping systems. This approach will allow us to determine what traits might be driving the observed differences in population dynamics, e.g. is it changes in planting time, light, etc What gives rise to variability? That is, how does environment (cropping system, terrain) affect dormancy? It may just be an inherent property modified by environment. Clearly, we need to consider recruiting someone with a genetic background to join our group. It was agreed upon that we would make an invitation to anyone interested in participating.