Biological Control Practices for High-Tunnel Crop Production
High tunnels are increasingly used for season extension throughout the country. The cultural management of the high tunnel environment falls somewhere in-between greenhouse and field production. Research has demonstrated that the use of bio-control’s or predatory insects to control pest populations in greenhouses to be effective and beneficial in decreasing and or eliminating the use of chemical pesticides. No-where is this practiced more than in Northern Europe. Prior to the commencement of our project, no research has been conducted on the use of ‘natural enemy’ species in the high tunnel environment whereby both beneficial and pest insects have ample opportunity to move in and out of the environment via the ventilation of the structure.
The goal of our project is: 1) to evaluate the use of predatory and parasitoid insects for pest control in the high tunnel environment by conducting extensive demonstration and research at the High Tunnel Research and Education Facility (HTREF) at Rock Springs, PA and 2) conducting on-farm research in conjunction with our two grower cooperators in the southeastern and northwestern part of Pennsylvania.
Information will be disseminated at presentations given throughout the region at professional meetings and workshops as well as at field days and Extension In-Service Training Days held at our research farm as well as at our grower cooperators farms. At the end of the project, all of our data will be coordinated and published in an informative pamphlet and distributed to our stakeholders.
1) Biological Pest Management Presentations:
Our objective of conducting practical research to assist high tunnel producers in implementing alternatives to chemical insecticides has progressed in 2004. An important component of our project was initiated this year by distributing a survey at several workshops throughout the Pennsylvania Vegetable Grower’s Association (PVGA) High Tunnel Production track at their annual meeting in January 2004, as well as at the Pennsylvania Association for Sustainable Agriculture (PASA) annual meeting in February 2004. During each of these symposiums, Lisa White presented an overview of the SARE project research as well as provided attendee’s with a detailed account of the many facets of biological pest management including the identification of key pests and the most salient natural enemies used to control them. In 2005, Dr. Mike Orzolek will be presenting the topic and research findings at the American Society of Plasticulture (ASP) annual meeting in Charleston, SC. In each presentation, an emphasis was placed not only upon the importation and release of natural enemies for pest management but also the conservation and encouragement of native populations of beneficial insects in high tunnel environments.
At the PVGA seminar, approximately 60 growers were in attendance, while at the PASA seminar, approximately 30 growers were in attendance. Of these approximate 90 attendants, survey’s were distributed and 40 survey results were returned for analysis.
3)Grower Field Day’s, High Tunnel Tours and Professional In-Service Training Events:
Outside of these two well attended presentations, in 2004, two Extension In –Service training events were held at the HTREF. Extension agents and agricultural educators from the Mid-Atlantic and Northeast region were presented with our research project insofar and a dialogue was established to help us better understand what they believe their stakeholders pest management needs are. We also hosted a grower field day whereby regional growers came to the HTREF to learn about various aspects of high tunnel production and our biological pest management work was once again presented.
Finally, in August, a field day was held in conjunction with PASA at one of our grower cooperators farms (Quiet Creek Herb Farm in Brookeville, PA). Here again, biological pest management was highlighted. Each summer at Ag Progress Days (APD), hundreds of citizens, including many farmers, researchers, children, and home gardeners are given tours at our facility. This year, a special detour was made to help educate these attendee’s about the importance of conserving beneficial insects and the role they play in biological pest management.
Providing presentations at PASA and PVGA allowed us the opportunity to fulfil our survey efforts. With these results, in our final year we will be able to better prepare for the publication of our high tunnel biological pest management publication. These survey results have helped us to narrow in on what information growers need to feel more confident about implementing biological pest management. Through this information, we will be well suited to meet their needs by focusing in on the exact type of information they feel is lacking from other sources. Throughout the 3 years of this project, we estimate that we have introduced the concept and practice of biological pest management to hundreds of producers, many of whom are currently producing in or are considering production in high tunnels. Our initial survey’s support a strong interest in using this type of pest management on farm.
2)Direct, Hands-On Training:
At the five separate events we held this year, our stakeholders, from growers to educators, and even children on school tours were introduced to the theory and application of biological pest management in the high tunnel environment. Many of the educators expressed a strong interest in this topic and requested additional ‘hands-on’ training in the high tunnels. A tour of extension agents and educators spent the morning scouting the high tunnels with our staff. This served as an excellent forum for them to become more comfortable identifying native natural enemies. All participants who had an interest were exposed to a variety of beneficial insects in various life stages, this developed into over an hour of intense insect scouting at the PASA sponsored field day at Quiet Creek Herb Farm. This direct learning experience proved to be invaluable as many of our stakeholders had heard of such insects like the green lacewing or parasitoid wasps but had never had the opportunity to view them up close and in person.
3)Marketing and Education of the Consumer:
Similarly, with the establishment of our PSU Cellar Market, we have initiated a forum in which we can communicate with the consumers of our biologically managed produce. In 2005 we anticipate a survey effort to help gage the interest and willingness of consumers to purchase food grown under the biological pest management model.
4)Applying Bio-Control Practices On Farm:
This year, we also continued our work with our grower cooperators. Lisa White, the project manager along with trained HTREF staff made monthly visits to each cooperator farm. Detailed training was initiated early each spring and interns on both farms conducted much of the subsequent scouting each week. Releases were made on each farm and control of our target pests, aphid and whitefly was achieved.
5)Managing On-Farm Challenges:
Pest management on each farm received mixed reviews as various new and challenging situations arose. Plant viruses posed significant threats to crops at the HTREF as well as at Cedar Meadow farm on tomato crops in 2004. This served as a learning experience for us all. Managing for viruses requires different strategies than managing solely for pest damage below the economic injury level as vector species such as thrips (and aphid and whitefly) can transmit viruses throughout a crop even at low densities. Moreover, while aphid and whitefly were very successfully controlled at all three research sites, spider mite presented a much more significant problem this year that required the use of new natural enemies and tactics for control. Unfortunately, we were not able to get ahead of the learning curve for managing spider mite biologically this year, but will be much better prepared next year.
6)Introducing Companion Plantings:
This year, in an effort to help to attract native natural enemies, companion plants were introduced into the six high tunnels used in this study at the HTREF. Observational results suggested that inter planting flowering pollen and nectar bearing species with our solanaceous crops did in fact contribute to the increase of native natural enemies in the high tunnel environment such as the ladybird beetle and green lacewing.
Impacts and Contributions/Outcomes
As described, the presentations made as well as the events hosted through out 2004 have reached a wide variety of growers, educators, and consumers and introduced and or expanded upon the practical application of biological pest management in the high tunnel environment. Survey results have helped us to begin to prepare for the compilation of the high tunnel biological pest management publication. Our marketing initiatives at Penn State have allowed us a forum in which to communicate directly with our consumers and identify awareness and social and economic interest in biologically managed crops. Another year of research at the HTREF has allowed us to track our successes as well as our difficulties in implementing biological pest management practices on the farm. Communication with our grower cooperators has also allowed us to refine our release recommendations and help identify methods in which application of these management practices can be improved. Working with market farmers has proven invaluable in allowing us to gage the effectiveness of biological controls, however, it has also demonstrated the need for growers who wish to use this method of management to commit to a course of learning, scouting and general observation of the ecological process on their farm. We have learned that without someone committed to these practices and principles, this method of pest management may not work well for everyone. The first and foremost factor to consider when contemplating the suitability of a biological pest management plan is a commitment to perform the weekly scouting.