A Survey of Biological Control Users in Midwest Greenhouse Operations

Abstract

A mail survey of commercial greenhouse operators in nine midwestern states obtained information on biological control agent use, sources of information for use, perceived successes and failures, and what would be needed for greenhouse operators to include biological control agents (predators and parasites and pathogens) in their pest-management programs. Questionnaires were sent to 480 commercial greenhouse operators in Iowa, Illinois, Kansas, Michigan, Minnesota, Missouri, Nebraska, South Dakota, and Wisconsin. The response rate was 56% ( n = 270). Less than 10% of respondents currently were using biological control agents as part of their pest management programs. Nonusers were unsure how to implement biological control (47%), had previously tried biological control agents but did not get desired control results (14%), or did not expect to get adequate control (37%). Current users cited thrips as the most difficult pest to control (54%), followed by aphids (25%), whiteflies (13%), and mealybugs (13%). Biological control agents were part of pest management on poinsettias, mums, New Guinea impatiens, peppers, and fuchsia. Respondents were queried as to the county and state location of their greenhouse operation, the size of their greenhouse operation in terms of covered square footage, the number of employees, and approximate gross sales. They also were asked to describe the highest level of education they had completed. Those who used biological control agents had higher levels of education than nonusers; 62% of users were college graduates or had completed some postgraduate education compared with 39% for nonusers. In response to the question “what do you need to begin using biological control in your greenhouse,” nonusers cited detailed training (57%), reduced cost (39%), and better control from biological control agents (44%).