Integrating Beetle Habitat into Pacific Northwest Farming Systems

Integrating Beetle Habitat into Pacific Northwest Farming Systems

Summary

The overall goal of this two-year project is to provide guidelines for implementing generalist predator habitat (beetle banks) on farms in the Pacific Northwest. Improving habitat for generalist predators such as ground beetles is a promising biological control strategy that offers an alternative to pesticide use. We have made significant progress toward this goal over the first year of the project. We conducted extensive field work that included developing detailed GIS-based habitat maps of each of our cooperating farms, conducted monthly spatially explicit censuses of beetle activity and documented prey consumption patterns both in the field and under controlled laboratory conditions. We used these data to develop habitat-based models that describe how the occurrence and diversity of beetle species varies seasonally and across habitat types on our study farms. Our preliminary results indicate that the habitat composition and diversity on a farm strongly influences the types and abundance of beetles found three. In addition, only a subset of beetles commonly found on a farm is active within production fields, and this activity varies seasonally. We did this work in collaboration with our cooperating farmers through direct one-on-one interaction over the course of the field season and through two winter project meetings where we discussed project goals, elicited feedback on preliminary results and planned broader outreach activities. We communicated early results from the project and provided more comprehensive information about management of on-farm conservation habitat during a summer farm walk and short course. The short course was attended by over 120 farmers and served as a venue for farmer-to-farmer exchanges that promoted the regional development of successful on-farm habitat enhancement practices. The short course also included a panel discussion that addressed ways to foster better cooperation and communication between regional farmers, researchers and government agencies.

In the second year of the project we will refine and make more robust our initial habitat models with a second year of field data. We will also incorporate our results into the outreach and management tools described in our proposal: a worksheet to help farmers evaluate and manage effective beetle habitat on their farm, extension documents describing beetle biology and the beneficial roles they play on farms and a website to publicize project information and to foster farmer interaction. We will also continue our active participatory outreach activities with both a winter and summer field class where we will introduce farmers to our habitat evaluation worksheets and include farmer-originated ways to map existing and future on-farm habitat.

Objectives/Performance Targets

Research

1. Develop a habitat-based model that predicts the occurrence of beetle species at the farm scale in Pacific Northwest agricultural landscapes.

2. Determine how the farm-scale arrangement of habitat types influences beetle activity patterns within fields.

3. Determine how activity within fields influences prey consumption beetle.

Outreach

4. Provide specific recommendations based on farmer-generated research questions.

5. Facilitate regional cooperation among farmers and researchers developing conservation biological control.

Accomplishments/Milestones

We have made significant progress towards achieving the project objects and performance targets described in the proposal.

Objective 1. Develop a habitat-based model that predicts the occurrence of beetle species at the farm scale in Pacific Northwest agricultural landscapes.

We produced detailed GIS-based vegetation maps for each of our five cooperator farms using high resolution aerial photographs and ground sampling (Fig. 1). We then developed models that are able to predict the likely composition of the beetle assemblage on a farm, based on the types of habitats found there. We did this by using NMS ordination to relate the information from the habitat maps to information on beetle activity that we acquired from extensive field sampling on each farm during the 2010 field season. The field sampling produced a spatially explicit data set of monthly beetle activity on each of our study farms.

Our models allow us to predict the composition of the overall beetle community on farms, as well as where particular beetle species are likely to be found on a farm (Table 1). For instance, several species of Omus are commonly found on our study farms, but these species are almost always associated with bordering forest habitats, never in production fields (Fig. 1).

We also developed over-wintering habitat models. We found that different habitat types differ in their overall beetle activity during the winter (Fig. 2). These results confirmed that grassy habitats and constructed beetle banks provide good over-wintering habitat for the set of species that are most commonly found within production fields during the summer.

Future tasks

We are in the process of repeating our winter and summer sampling regime to provide an additional year of data. These data will allow us to refine our habitat models and to evaluate the degree of year-to-year variability in beetle assemblages on farms.

Objective 2. Determine how the farm-scale arrangement of habitat types influences beetle activity patterns within fields.

We used our extensive spatially explicit sampling of beetle activity to develop a comprehensive picture of seasonal beetle activity across the complex landscapes of our cooperating farms. Our field data allowed us to construct species-specific profiles of beetle activity (Fig. 3). These profiles indicate that beetles differ significantly in their seasonal activity patterns (Fig. 3). Some species are active early in the season (e.g. Amara littoralis, Omus sp), some species are active late in the season (e.g. Pterostichus algidus) and some species have bi-modal activity patterns (e.g. Nebria brevicaulis). In additional, species differ in the relative use of particular habitats. For instance, Anisodactilus californicus and P. melanarius were found to be significantly associated with the center of production fields.

Future tasks

Our next step in this analysis is to use SADIE analysis to develop a more detailed spatially and temporally explicit model of beetle activity. Our current species profiles are a nice overview representation of when and where particular beetle species are likely to be found in a farm landscape. Our planned SADIE analysis will allow us to develop explicit maps of likely beetle activity over a season. This analysis will be made robust with a second year of data collection, which is why we have postponed doing this work until we have two full years of data.

Objective 3. Determine how activity within fields influences prey consumption beetles.

Over the course of our summer sampling period, we tested for differences among species in per capita feeding rate by exposing them to sentinel prey items for 24 hours in experimental feeding arenas. This provided information on how per capita feeding voracity varied across species and season. We found significant variation in both respects (Fig. 4). Some species (e.g. P. melanarius) were highly voracious across the entire summer, while many others exhibited distinct seasonality in their relative prey consumption (Fig. 4). These results indicate that translating beetle activity into estimates of target prey consumption is not straightforward. Combining our information about seasonal prey consumption variation with patterns of seasonal beetle activity will allow us to produce a more accurate picture target prey consumption intensity across our farm landscapes.

Future tasks

We have two main tasks to complete. The first is to incorporate our field measures of prey consumption rates into our analysis. Along the same spatially explicit sampling grid that we used to measure beetle activity, we also assessed prey consumption. We plan to incorporate these data into our SADIE analysis to test whether different habitat types have different overall levels of prey consumption and whether prey consumption is spatially correlated with beetle activity. We had some technical difficulties in collecting the prey card data this past season that we hope to correct in this upcoming field season.

Our second task is to produce detailed maps of relative prey consumption for each of our farms by combining our maps of beetle activity with our information on their relative prey consumption.

Objective 4. Provide specific recommendations based on farmer-generated research questions.

We collaborated with our participating farmers through several grower-researcher meetings, on-farm demonstrations of research activities and field classes to report our early research findings and to ascertain the most relevant way to design our research effort and outreach tools. These included:

1. A winter project meeting at farmer-cooperator Brad Bailie’s Lenwood Farms in Connell, Washington on 12/8/09. We discussed his project goals and role, current farm habitat, plans for future habitat, 2010 project sampling for predacious ground beetles and a 2010 farm walk at his farm. We visited two already established beetle banks of rye and various non-native grasses and one new bank testing native Columbia basin grasses of sand dropseed, Idaho fescue, blue bunch grass and basin wild rye. Brad’s goals for this project are to learn more about what effects these insectary plantings are having on his farm in terms of crop pest management, and what new techniques can he employ to better manage the insectary plantings.

2. A winter project meeting with the four Oregon farmer-participators in January 2010. We discussed and planned project goals, roles, current farm habitats, future habitat plans, 2010 project sampling schedules for predacious ground beetles and a 2010 farm walk. It was decided that the Oregon farm walk would be in July at Persephone Farm in Lebanon, OR. Persephone Farm is home to two beetle banks, one which is four years old, and two in field hedgerows. The Oregon farmers’ project goals are identical to Brad’s goals in Washington. With the exception of Peter Kenagy of Kenagy Family Farms who already has extensive mature insectary and conservation plantings on his 360 acre vegetable farm, all have plans to create new insectary plantings in addition to their current on-farm habitat.

3. A farm walk and short course on Lenwood Farms in Connell, WA, June 23, 2010 (Fig. 5). This course was jointly sponsored by this project, Lenwood Farms, the Western Region Conservation Biological Control Work Group, farmer-generated industry funds, and in-kind contributions from the USDA, NRCS, Plant Material’s Center of Corvallis, OR, the National Center for Alternative Technology (NCAT) California Office, the Integrated Plant Protection Center, OSU, the Pollinator Program for Xerces Society for Invertebrate Conservation, Portland METRO’s conservation program and WA’s Sound Horticulture. The walk, called the 2nd Annual Biodiversity Working for Farmers Tour/Short Course, was attended by more than 120 area farmers, industry representatives, extension researchers, conservation agency personnel, one WA Senator and various city and county representatives.

Lenwood Farms is a 600 acre certified organic potato, pea, squash and grain farm in the Columbia Basin. Ten invited speakers and four FAB Work Group speakers, including members of this project, used the farm as a teaching laboratory. We presented information and early results from this project’s on-farm research, as well as other research being conducted on the farm examining the relationship between habitat diversity and ecosystem services. The short course program also included a discussion of issues and policies that hinder and support local conservation practices and organizations that aid in their implementation and adoption.

We developed a knowledge and perception (KAP) survey that was given to all participating farmers in March 2010 (Appendix I). We will give this survey to the farmers at the end of the project as well.

Future tasks

We had to cancel or planned summer 2010 farm walk at Persephone Farm due to an overwhelmingly too busy schedule for the farmers. Summer 2010 was a very trying summer for most Willamette Valley farmers as the weather was very cold and wet long into July, making getting into the field difficult and delaying most field production work. An unsuccessful attempt was made to set a substitute walk in early fall with other growers but similar problems and short notice worked against us. We expect the 2011 Oregon field class summer component to go more smoothly.

We are combining the 2011 winter project meeting and winter field class for the participating farmers’ convenience and to enable us to begin working with them and other farmers as well on the habitat evaluation worksheets. We anticipate the worksheets will include farmer-originated ways to map existing and future on-farm habitat. At this meeting we will present the results and analysis from our previous season’s field work.

Objective 5. Facilitate regional cooperation among farmers and researchers developing conservation biological control.

The farmer meetings described above also served as venues for farmer-to-farmer exchanges that promoted the regional development of successful on-farm habitat enhancement practices. The 2010 Tour/Short Course at Lenwood Farms included a dynamic farmer panel with four local farmers, including Senator Mark Schoester who farms over 12,000 acres of dryland wheat, this project’s Gwendolyn Ellen, and the executive director of Organically Grown Company (OGC) which buys Lenwood Farms produce. The panel discussed the potential role that on-farm biodiversity enhancement and conservation practices could play in improving farm income and sustainability, as well as some of the constraints that may limit the potential for the full benefits of these practices to be realized. The panel specifically addressed ways to foster better cooperation and communication between regional farmers, researchers and government agencies.

We created a press release of the farm walk/course that resulted in extensive media coverage. Articles went out in many WA and other Pacific Northwest newspapers. An article about our program was even reported on an Asian agricultural blog. An article highlighting the conservation practices on Lenwood Farms was published in the October 2010 issue of the American Vegetable Association.

All the participating farmers in our project have led tours and given presentations to a broad audience of farmers, students, agricultural professionals and consumers in 2010. In these tours and presentations, they are quick to highlight the conservation habitat on their farms and the many functions it provides in terms of ecological services by the beneficial beetles and other insects, native pollinators and wildlife they attract and support.

Future tasks

We plan to develop a project website as well as a collaborative workspace on eOrganic.

Impacts and Contributions/Outcomes

We have made significant progress towards meeting our short-term outcomes. Our farm walk/short course at Lenwood Farms (that included over 120 farmers) and our meetings with project farmers have introduced regional farmers to the ecology, biology and potential ecological services that predacious ground beetles provide farms. We also used our previous knowledge and results from our first field season to familiarize farmers with the types of habitats that foster beetle activity, as well as the concept of creating habitat to promote predaceous ground beetles and other beneficial arthropods. These events have trained farmers to evaluate their farms in terms of beetle habitat and have demonstrated practices they can use to enhance this habitat on their own farms.

Results from our first year of research has improved our ability to make more specific recommendations about the types of habitat that will attract specific beetle species as well as the potential impact this will have on pest suppression within production fields.

We have also begun to see some more medium-term impacts from our project. Four of the five cooperating farmers have plans to create new beetle/insectary plantings in addition to their current on-farm habitat.

Future tasks

In the second year of this project we will incorporate this new information into specific tools that will assist farmers in planning and implementing effective beetle habitat on their farm. We will give our knowledge assessment survey to farmers a second time to assess the degree to which our project empowers farmers to actively manage habitat on their farms.

• Table 1.
• Figure 1
• Figure 2
• Appendix 1
• Figure 4
• Figure 3
• Figure 5

Collaborators: