TY - JOUR
T1 - Enlisting an underappreciated clientele
T2 - Public participation in distribution and evaluation of natural enemies in urban landscapes
AU - Paine, Timothy D.
AU - Millar, Jocelyn G.
AU - Bellows, Thomas S.
AU - Hanks, Lawrence M.
N1 - Funding Information:
We present an approach for generating public support, including financial support, that has allowed us to introduce, distribute, and evaluate natural enemy success in urban landscape systems. This approach is an alternative to conventional research grant support and enables traditional funding sources to be leveraged heavily. In all cases where we have applied this approach, the initial phases of pest assessment, foreign exploration, natural enemy selection, and development of rearing methods have been conducted with an initial base of traditional grant support. During this development period, we have also undertaken extensive public education programs that provide basic information through the media, University of California Cooperative Extension, industry groups, and civic associations. The disseminated information includes details about the pest, the nature of the injury and the cost of damage, the variety of management options available (including the cost, potential benefit, and potential risks or limitations), and the potential for integration of those options for great-
Funding Information:
A major effort was instituted to describe the biology of the whitefly and to introduce natural enemies as a biological control solution to the problem. The collaborative biological control program between the University of California-Riverside and the California Department of Food and Agriculture initially was funded as grants from agricultural commodity industries, the University, city and county governments, and State sources. These grants enabled the program to obtain two species of natural enemies in September 1989 (the hymenopteran parasitoid Encarsia inaron [Walker] and the coleopteran predator Clitostethus arcuatus [Rossi]), develop mass production techniques for whitefly hosts and the natural enemies, and initiate the release program within eight months. By 1990, populations of the whitefly in the release areas in Riverside were reduced by 10,000-fold (Bellows et al. 1992a). This can be explained partially by a net reproductive rate of 69.3 and a mean generation time of about 19 days for the parasitoid in the preferred nymphal instar of the host at 25°C (Gould et al. 1995). By 1991, populations of S. phillyreae and E. inaron were at very low equilibrium densities in Riverside (Bellows et al. 1992a; Gould et al. 1992a, b). The predator also established at release sites. While highly effective in the laboratory (Bellows et al. 1992b), the impact of the beetle on whitefly populations in the field was overshadowed by the effects of the parasitoid. The parasitoid worked extremely well at reducing whitefly populations in the initial release centers. The subsequent problem was to provide similar levels of control throughout the infested area. The collaborative rearing and distribution program was supplemented by an at-cost parasitoid distribution program developed by University of California-Riverside through University of California Cooperative Extension. Release trials had indicated that a population of parasitoids could be established with a minimum release of 250 individuals. This set the minimum order size. After rearing costs were analyzed and a value of $1 per individual wasp was determined, the public was notified through the press that parasites were available. Orders were received from throughout the state, and more than 120,000 parasites were distributed. Although it was expected initially that the cost would limit orders to institutional clients, the greatest number of requests came from private individuals. The price for the parasites was a bargain relative to the cost of spraying large trees several times each season and eliminated any potentially detrimental effects of using pesticide sprays. In some cases, individuals in neighborhoods went door-to-door to collect money and then placed a communal order. The result was a rapid broad distribution and establishment of the wasp followed by a rapid and permanent decline in the whitefly populations. The biological control program successfully reduced the populations of the whitefly below damaging thresholds. Across 28 of 46 counties in California, the benefit of the biological control program from reduction in direct aesthetic injury to just Fraxinus and Pyrus planted as street trees has been estimated to have been $221,047,147 at wholesale tree values or $300,028,294 at retail tree values (Jetter and Klonsky 1994). The total cost of the biological control program was approximately $1,224,324, a value that included annual salary figures for individuals dividing their efforts among this project and several other unrelated projects. Thus, the rate of return on each dollar invested in biological control was at least $181 at wholesale tree values and $245 at retail values for only two genera of street trees (Jetter and Klonsky 1994). The rate of return probably is significantly higher not only when all hosts and all landscape sites are considered but also when
Funding Information:
As with the Siphoninus phillyreae research program, much of the support for the work through the research and development phase was provided through grants from industry, university, and state agency sources. However, the project has entered the mass distribution phase for A. longoi and S. lepidus. The model for at-cost distribution of natural enemies developed for the Siphoninus phillyreae control effort has been modified and adapted for natural enemies of eucalyptus longhorned borer. Siphoninus phillyreaewas a significant urban landscape pest, but the injury was primarily aesthetic or nuisance in nature. Trees could have a range of infestation levels, and natural enemies could be released/established as a remedial solution. In contrast, eucalyptus longhorned borer causes direct mortality, and, once infested, the tree usually is killed. Natural enemies cannot provide the owner of an individual tree with either remedial relief or prophylactic protection. Natural enemies for this insect are useful for reducing beetle populations across a broader area which will, in turn, reduce the risk to an individual tree, particularly if tree health is maintained at a high level through proper tree care (Paine et al. 1993,1995). Consequently, information about the at-cost availability of the wasps has not
Publisher Copyright:
© 2018 Entomological Society of America.
PY - 1997
Y1 - 1997
N2 - Since the turn of the century, there has been a significant shift in the population of the United States from a rural to a predominately urban and suburban society. The process of urbanization created new landscapes to replace the natural areas or farms that previously occupied the land. To a great extent, these landscapes are artificial communities comprised of diverse assemblages of native and exotic species that may be comparable in diversity to tropical rain forests (Owen 1983). With respect to woody ornamental plants alone, Frankie and Ehler (1978) reported 322 species (132 species of trees, 147 species of shrubs, and 53 species of vines and ground covers) were planted in Austin, TX, and 123 species of trees were planted in Berkeley, CA. In total, 318 plant species, including 143 native and 175 non-native, exotic species, were planted in a single study garden in Leicester in the United Kingdom (Owen 1983). These urban landscapes, which include both annual and perennial species planted at densities or separations not normally found in natural habitats, also are characterized by high levels of patchiness and structural diversity (Owen 1983, Flanders 1986). In addition, the physical barriers associated with buildings, transportation corridors, parks, and industrial complexes add significant levels of artificial spatial complexity to the environment (Frankie and Ehler 1978).
AB - Since the turn of the century, there has been a significant shift in the population of the United States from a rural to a predominately urban and suburban society. The process of urbanization created new landscapes to replace the natural areas or farms that previously occupied the land. To a great extent, these landscapes are artificial communities comprised of diverse assemblages of native and exotic species that may be comparable in diversity to tropical rain forests (Owen 1983). With respect to woody ornamental plants alone, Frankie and Ehler (1978) reported 322 species (132 species of trees, 147 species of shrubs, and 53 species of vines and ground covers) were planted in Austin, TX, and 123 species of trees were planted in Berkeley, CA. In total, 318 plant species, including 143 native and 175 non-native, exotic species, were planted in a single study garden in Leicester in the United Kingdom (Owen 1983). These urban landscapes, which include both annual and perennial species planted at densities or separations not normally found in natural habitats, also are characterized by high levels of patchiness and structural diversity (Owen 1983, Flanders 1986). In addition, the physical barriers associated with buildings, transportation corridors, parks, and industrial complexes add significant levels of artificial spatial complexity to the environment (Frankie and Ehler 1978).
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U2 - 10.1093/ae/43.3.163
DO - 10.1093/ae/43.3.163
M3 - Article
AN - SCOPUS:0000388360
SN - 1046-2821
VL - 43
SP - 163
EP - 173
JO - American Entomologist
JF - American Entomologist
IS - 3
ER -