Measuring the Ecological and Economic Costs & Benefits of Native Perennial Floral Strip Addition on Beneficial Insect Abundance & Arthropod-mediated Ecosystem Services within Ohio

View the project final report

Commodities

• Vegetables: cucurbits
• Additional Plants: native plants, ornamentals

Practices

• Crop Production: conservation tillage
• Education and Training: extension, on-farm/ranch research, participatory research, workshop
• Farm Business Management: agricultural finance, feasibility study
• Natural Resources/Environment: biodiversity, habitat enhancement, hedgerows, hedges - grass, indicators
• Pest Management: biological control, cultural control, field monitoring/scouting, integrated pest management
• Production Systems: agroecosystems, holistic management, permaculture
• Sustainable Communities: local and regional food systems

Disturbances that accompany the production of agricultural crops such as tillage, pesticide application, and harvesting can negatively impact beneficial arthropod communities and the arthropod-mediated ecosystem services they support. Habitat management examines methods that alter agricultural habitats to lessen negative disturbances and optimize the performance of beneficial insects. The introduction of floral resources to provide habitat and alternative food and prey for beneficial insects has been shown to increase their diversity and abundance. This project investigated how localized habitat management and landscape composition affected the abundance and activity of pollinators and natural enemies in pumpkin agroecosystems. Localized habitat additions included either a pair of non-native annual floral strips consisting of sweet alyssum (Lobularia maritima) or a swath of perennials consisting of native Ohio forbs and grasses. I compared beneficial insect abundance, diversity, and biocontrol and pollination services within 6 treatment (floral strips), 6 control (crop produced adjacent to mown grass) pumpkin farms across Ohio, and also compared pollination and biocontrol services with landscape composition surrounding those sites. Data on beneficial arthropod abundance and diversity was collected using pitfall traps, pan traps, and video footage. Predation and parasitism of cucumber beetle and squash bug eggs and parasitism of adults was compared across treatment and control pumpkin fields. Pollination service and the diversity and activity of the pollinator community were also compared within treatment and control fields, and across time. Additionally, an economic analysis of the net revenue between treatment and control farms was conducted to evaluate the feasibility of this habitat management tactic. This study contributed to NCR-SARE’s broad-based goals by providing vegetable growers and extension agents with information on the effectiveness and economics of habitat management within a vegetable cropping system. This information will prove useful in reducing costs of chemical insecticides and in enhancing environmental quality and the natural resources base on which agriculture depends.

Introduction:

My project builds on SARE­funded research by measuring both the economic and ecological costs and benefits of incorporating native perennial floral resource strips in an annual vegetable cropping system (Fiedler and Landis, 2004; Walton and Isaacs, 2007; Blaauw and Isaacs, 2008 and 2009). Further, my research will measure not only the abundance of beneficial insects, but also both the pollination and biocontrol services they support. This was a two-year study (2011-2012), of which NCR-SARE funding was only applied to 2012. Data processing for the 2012 pollination experiments has not yet been finished for all objectives. Collected pollinator data from 2011 was similar, and will be covered in this report. However, research questions for 2011 were more to do with large-scale landscape effects on beneficial insects, rather than local habitat additions.

These were modified from the proposal as circumstances changed.
1. Determine if landscape composition at 500, 1000, and 1500 m radii around pumpkin plantings affects the ecosystem service provided by native and managed bees.
2. Determine if the addition of a native perennial floral strip enhances the biocontrol services of generalist predators and parasitoids.