Progress 06/01/02 to 05/31/05
A strategic set of IPM tools has been developed. We not only validated a monitoring system for detecting flight (degree-day model and yellow water traps), assessing egg incidence and crop damage, we tested new chemistries for controlling eggs and adults. We also explored more effective application timing and techniques for targeting the egg stage at the base of plants. We studied spatial management of fields (as described below); analyzed damage levels relative to planting and harvest schedules; experimented with row covers and exclusion fences as barriers from egg-laying females; investigated field sanitation and clean-up of infested roots and wild host plants; tested irrigation management for egg control, and confirmed that cultivation practices after harvest reduce future CM puparia loads. Here are only a few significant results and accomplishments from the research conducted in the northern Willamette Valley from years 2001 through 2005 that contribute greatly to
reducing chlorpyrifos use in Brassica crop production. Our intentions were to promote practical, economic and achievable solutions to higher the probability of adoption and success. The results of our investigation have been disseminated through various means such as newsletters, one-on-one grower discussions, workshops, professional meetings, and a website. We are preparing refereed-journal articles and extension bulletins. The development of a GIS-IPM mapping tool can be effective for identifying low- and high-risk maggot sources and provides a useful visual presentation of maggot population levels across a region. Certain conditions favor cabbage maggot infestations as seen visually on a map prepared by Excel-based GIS system. In commercial plantings many of these conditions can be avoided. Such conditions that proved to be statistically significant from this study include: 1) Planting neighboring fields in succession increases risk in later plantings as flies move from harvested
fields to neighboring fields. Consecutive annual plantings of Brassicas could prove damaging especially if a field is planted adjacent to field with high damage; 2) Plantings near overwintering sources raise the risk of damage in the spring; 3) Fields planted near abundant wild Brassica weed hosts (wild radish, black radish, wild mustard) and cull piles had higher damage rates- Sanitation is key; 4) Fields surrounded by brush barriers and woods, a place of rest and feeding were notably higher in damage; 5) Fields planted adjacent to houses, nurseries and other buildings may need special efforts as they proved to have higher damage; 6) Previous history of cabbage maggot damage have higher damage ratings; 7) Fields that are separated in time (>550DD) and space (>225 m = .14 mile) from infested fields have less damage; 8) Avoid planting during the spring when fly densities in water traps are high, and 9) Rutabaga plantings had higher levels of damage than turnip or radish crops, so using
this crop as a trap crop might be worth exploring. Ultimately, the mapping tool could be used by a grower or regional community of growers to better manage plantings in space and time and thereby minimize pest levels.
We expect the impact of the cabbage maggot IPM toolbox and information to be widespread throughout the Pacific Northwest and many other Brassica growing regions extending beyond Oregon. In addition, the findings are applicable to closely related fly species with similar phenologies such as seed corn maggot (Delia platura), onion maggot (Delia antigua) and the carrot rust fly (Psila rosae). If the commercially viable monitoring plan, along with preventative and cultural practices are implemented than fewer pesticides will be used. Spatial field separation (.14 mile) from overwintering or seasonal maggot sources could dramatically reduce damage levels in the spring and chemical need. Also, employing timely planting and harvesting schedules could reduce maggot damage. We predict that a grower could reduce chemical input by at least 1/3, and in some cases 1/2 when the crop is grown during low risk windows of pest presence. The IPM education heightened growers awareness and
confidence. Growers have seen the available tool choices and have better evidence that IPM techniques can work. A top acreage grower hired a monitoring scout for the first time to inspect fields for pests. We also shared the IPM philosophy with neighbors surrounding the fields, a good opportunity to build relationships. Changes in IPM adoption behavior leads directly to changes in pesticide use patterns. The PEST Plan will serve as a great prototype to measure the impact and rate adoption of IPM tools, and can be modified as a template for evaluating other pest management programs.
- Produced 5 newsletters called Maggot Mania News for growers highlighting pesticide resistance, degree-day modeling, spatial rotation and mapping, sampling techniques, and other alternative management methods. 2003-2005.
- Bruck, D.J., Snelling, J., Dreves A. J. , and S. Jaronski. 2005. Laboratory bioassays of entomopathogenic fungi for control of Delia radicum (l.) larvae. Journal of Invertebrate Pathology. 89:179-183.
- Dreves, A. J., D. Dalthorp, and A. G. Stone. 2005. Spring emergence and seasonal flight activity of adult cabbage maggots, Delia radicum (L.) (Diptera: Anthomyiidae) in western Oregon. Environmental Entomology. (In review). Dreves, A. J. and D. Dalthorp. 2005. Monitoring flight activity, oviposition, and damage of the cabbage maggot, Delia radicum L. (Diptera: Anthomyiidae), in Brassica root crops. (currently in progress, but not submitted).
- Herring, P. 2005. Urban Farmer. Oregons Agricultural Progress Summer 2005.
- Dalthorp, D, and A. J. Dreves. Temporal and spatial management of cabbage maggots, Delia radicum (L.) (Diptera: Anthomyiidae). (currently in progress, but not submitted; 2006).
- Oregon State University Extension Bulletins titled,Take a Closer Look: life cycle and biology of the cabbage maggot in Oregon. (Writing currently in progress, expected completion Mar 2006).
- Oregon State University Extension bulletin titled, Take a Closer Look: Monitoring and Management of cabbage maggots.(Writing currently in progress, expected completion Mar 2006).
- Created laminated educational 3 x 4 inch cards contained on a ring outlining monitoring and IPM practices in bulleted format for easy grower use. 2003-2004.
- June 26, 2003; Aurora OR; MagNet: IPM strategies including monitoring, mapping and treating for maggots; A 3-Hour Hands-on field day, which included: Monitoring adult flight with yellow water traps; Assessing egg levels in a field to target high infestation levels; Understanding life cycle & identification of fly; Mapping damage using GIS techniques to more effectively time plantings; Application techniques to increase effectiveness & timing of treatments.
- Selected symposia, invited presentations, workshops, round table discussions, etc including: Nov 20, 2002; Fort Lauderdale FL; Annual Entomological Society of America Meeting Presentation & titled: MagNet: Insights into the Management of Root Maggots (Delia radicum) in Brassicaceae Crops.
- Dec 13, 2002; OSU Corvallis OR; OSU-IPPC Round Table Discussion on IPM in Oregon: 15 minute talk on Cabbage Root Fly (Delia radicum) Management on a Regional Scale. Included approaches, limitations, and outcomes.
- Mar 1, 2003; OSU; Horticulture Dept; Maggot Mania Newsletter #1 released to growers-Spring Issue 03 (introduce project and objectives).
- Mar 15, 2003; NWREC Station-Aurora OR; GIS Regional Mapping Computer Demonstration titled,Why and Why not Use Field Mapping?
- Apr 8, 2003; Indianapolis IN; Fourth National Integrated Pest Management Symposium-Poster MagNet: Maggot Management- IPM and GIS mapping.
- June 15, 2003; Wash DC; Invited Organic Transitions Grant Review Panel Member.
- June 23, 2003; Vancouver WA; EPA work planning meeting: Special Guest Talk titled, Building an IPM Program and Ways to Measure Success.
- July 1, 2003; Corvallis OR; six additional laminated educational information cards released for grower use.
- Aug 15, 2003; OSU; Horticulture Dept; MagNet Mania Newsletter -Fall 03 issue 2 (alternative methods).
- Sept 18, 2003; Aurora OR; Oregon Fresh Market Growers Association Meeting- Cabbage Maggot IPM Program- Canada and US Vegetable Production Talk and Proceedings.
- Feb 18-9, 2004; Abbotsford BC Canada; Invited speaker to 46th Annual Horticulture Growers Short Course-Pacific Agriculture Show. Topic Presented, Maggot IPM and presented a Mini-Workshop demonstrating use of laminated education cards as a valuable guidance tool (see evaluation forms).
- Feb 16, 2004; Corvallis OR; Presented, How to Measure IPM Adoption-the PEST Plan. A follow-up discussion involved: 1. Development of IPM Guidelines for Oregon; 2. Measurement of IPM adoption; 3. Measurement of IPM impact and risk reduction; 4. Maximizing benefits to other agencies and partners (commodity groups, ODA, NRCS etc.).
- Mar 7, 2004; OSU; Horticulture Dept; MagNet Mania Newsletter -Spring 04 issue 3 (fungus use for maggot control).
- Mar 16, 2004; Corvallis OR; Presented, GPS-GIS IPM tool for Growers, a mini-workshop demonstrating mapping and use of laminated educational IPM cards at Field Day Events
- Mar 31, 2004; NWREC, Canby OR;A Round Table Grower Discussion titled, Where are we headed in the Maggot World? Presented 2000-2003 data on: 1) phenology and CM life cycle on how this relates to planting dates, damage levels, and harvest period; 2) 12 trials explaining best application techniques, chemicals with increased efficacy, and new potential chemistries based on results; 3) spring cultivation trials.
- Nov 2, 2004; Canby OR; Monitoring Training titled, Transfer of Technology to Scouts and a Vegetable Grower Workshop titled, Why monitor on the farm?
- Nov 16, 2004; Salt Lake City Utah; Entomological Society of America Meetings. Presented, Know thy Enemy: Strategies for managing the cabbage maggot, Delia radicum L.
- Nov 17, 2004; Salt Lake City UT; Co-Moderator for Root Maggot Symposium titled, Insights into Biology and Management of Root Maggot Pests.
- Jan 19-22, 2005; Pacific Grove CA; 25th Anniversary Ecological Farming Conference. Presented, Lifestyles of the Top 10 Beasts on the Farm. Highlighted cabbage maggot IPM.
- Mar 13, 2005; Aurora OR; Grower round table discussion regarding yearly MagNet IPM plan-on farm experiments.
- Apr 19-20, 2005; Portland OR; WCC-69 IPM Systems Tour- Highlighted Montecucco Farm and the MagNet Project. Discussed their pest management system; synthesized IPM practice use, system components and IPM behavior and limitations. IPPC Systems Workshop Proceedings.
- May 19, 2005; Corvallis OR; OSU Horticulture Seminar Series. Presented, Are IPM tools making it to the field?
- June 22, 2005; Aurora OR; Oregon Fresh Market Growers Association Spring Meeting-Vegetable Production and Insect Management. Presented MagNet IPM project update.
- July 29, 2005; Corvallis OR; OSU Mini-College Master Gardener Workshop titled, Cabbage Maggots and other pests in Action.
- Aug 30, 2005; Portland OR; IPM Indicators Workshop (USDA, CREES, IPM Regions, EPA). An Invited speaker for MagNet project and grantees perspective on grant reporting.
- Aug 31, 2005; OSU; Horticulture Dept; MagNet Mania Newsletter -Summer 05 issue 4 (Resistance).
- Oct 15, 2005; OSU; Horticulture Dept; MagNet Mania Newsletter -Fall 05 issue 5 (Degree-day modeling).
- Nov 3, 2005; Canby OR; Scheduled to discuss IPM Recommendations to pilot MagNet growers.
Progress 01/01/03 to 12/31/03
The objective of this project is to reduce grower dependence on Lorsban (chlorpyrifos) to manage cabbage maggot (Delia radicum). A strategic IPM toolbox of management strategies is under development. The plan includes: monitoring (adults, eggs, and damage); predictive degree-day modeling; spatial management (through monitoring and a regional grower-friendly GIS mapping system); fall cultivation; habitat enhancement for natural enemies (e.g. straw mulches); and alternative chemistries and application methods. A grower survey tool will be used to evaluate program impacts and grower IPM adoption over time. Results: 2001-2003 water trap data indicate that there are 3-5 CM flights each year in the northern Willamette Valley; there were at least 4 in 2003. The yellow water traps were adequate for monitoring seasonal trends in adult flies, but cannot be used as predictors of infestation in individual fields. The DD model may be a viable strategy for predicting first and last
flight. The intermediate flights overlap with the first flight, generating an extended period of risk in the late spring and early summer. Preliminary analyses indicate that there is no simple relationship between crop planting date and damage levels. This is due to the fact that many factors other than CM phenology impact damage, including management practices, landscape factors, the proximity to other infested fields, and crop developmental stage. There was a positive relationship between cumulative egg counts and crop damage. Attractiveness for egg-laying is impacted by crop development. Flies preferentially lay eggs at the base of root crop plants with 5-9 developing leaves. However, flies will lay eggs on older plants if the preferred stage is not available. Lorsban 4E remains the most effective pesticide, especially if applied in the furrow. However, efficacy is not 100% and is therefore insufficient for these zero-tolerance root crops. There may be CM resistance to Lorsban as
has been shown previously by Canadian researchers. Fipronil applied in-furrow and Fipronil seed treatments showed the most efficacy as alternatives to Lorsban 4E. Chlorpyrifos- and Spinosad-treated seed also showed efficacy but lost protection at 4 weeks after planting. In-furrow applications were significantly more effective compared to over-the-row applications. There are many commercially available GIS software packages, but most of these are expensive, difficult to use, and require a significant time commitment to master. Our approach has been to add GIS capabilities to software programs that growers are already familiar with. A model CM GIS-IPM tool has been developed and is being refined to: 1) serve as a research tool to develop risk assessment criteria and evaluate CM dynamics in time and space, and 2) assist growers in regional spatial CM management. This GIS provides risk analysis, mapping and visualization tools within Microsoft Excel that supplement standard data entry and
spreadsheet analyses. Data can also be exported or imported in formats that are compatible with most GIS packages. Three years of monitoring data is currently being evaluated with the GIS-IPM tool.
The objective of this project is to reduce chlorpyrifos use in cruciferous root crop production. Cabbage family crop growers are highly dependent on the use of chlorpyrifos (Lorsban) for control of their most important pest, the cabbage maggot. Forty one percent of broccoli acreage, 31% of cauliflower, and 100% of root crop acreage are prophylactically treated with chlorpyrifos. Chlorpyrifos has been shown to be neurotoxic to animals and aquatic organisms. EPA has invoked the 10-fold safety factor for chlorpyrifos, and all uses are at risk of termination. Chlorpyrifos is the second most frequently detected insecticide in surface waters of the Willamette Basin. Thus far, we have 1) identified monitoring tools, developed a degree day model, and taught growers to monitor so they can identify fields with and without infestations and better time sprays, 2) identified most effective pesticide application techniques and alternative chemicals, 3) developed an IPM-GIS that
should help growers plan plantings in time and space to reduce maggot damage.
- No publications reported this period