Preventing horticultural introductions of invasive plants: potential efficacy of voluntary initiatives

Abstract

Although prevention is the most costeffective way to avoid the enormous expenses associated with plant invasions, invasive plants continue to be imported as trade commodities for horticultural use. With very little government regulation of horticultural imports of invasive plants, efforts have turned toward fostering voluntary initiatives to encourage self-regulation by the horticulture trade. Our study takes the first step toward evaluating the potential success of these voluntary initiatives. We conducted a survey of nursery professionals to gauge their perceptions of invasive species, the role of the horticulture trade in invasive plant introductions, and their participation-potential and actual-in preventive measures outlined in the St Louis Voluntary Codes of Conduct for nursery professionals. We found nursery professionals to be highly aware of invasive plants and to accept responsibility as a trade for horticultural introductions. Although only 7% of respondents had heard of the St Louis Voluntary Codes of Conduct, the majority (57%) reported having participated in at least two of seven preventive measures, and most (78%) reported willingness to engage in the majority of preventive measures. We found that several factors significantly predict increased participation in preventive measures, particularly awareness of invasive plants and involvement in trade associations. We also identified incentives and obstacles to participating in preventive behaviors, including ''concern for the environment'' and ''lack of information,'' respectively. Our results suggest that participation in voluntary initiatives will improve through increased outreach, and we provide specific recommendations for improving participation in voluntary programs in the horticulture trade.

Conceptual Frameworks and Methods for Advancing Invasion Ecology

“…Domain A: Difficulties arising from society and its relationship to biological invasions, measures that can be taken to overcome them and consequences for the scientific approach of invasion ecology; letters and numbers in parentheses refer to Perrings et al (2010b); c Bremner and Park (2007), Burt et al (2007), Byron (2008); d Mack et al (2000), Moore et al (2010); e Fischer and van der Wal (2007); f Andreu et al (2009); g Bodey et al (2010) to analyze, explain, and predict. Invasion processes are complex (Lodge 1993;Hayes and Barry 2008;B1 in Table 2) and context-dependent (Zedler and Kercher 2004;Gurevitch et al 2008;Blackburn et al 2009) (B2 in Table 2).…”

The role of intraspecific hybridization in the evolution of invasiveness: a case study of the ornamental pear tree Pyrus calleryana

“…Intraspecific hybridization is most likely to follow multiple introductions of a species (Kolbe et al 2004), especially non-native species that are transplanted from different parts of their native range into a new locality. Multiple introductions may be done deliberately, for example, when plant species are imported for horticulture (Reichard and White 2001;Burt et al 2007) or accidentally as when seeds are introduced as contaminants during shipping (Sakai et al 2001). Once introduced, genetically distinct individuals may cross-pollinate to create novel genotypes through admixture that otherwise would never have been possible in the native environment (Arnold 1997;Novak and Mack 2005;Roman and Darling 2007).…”

Assessing Stakeholder Perspectives on Invasive Plants to Inform Risk Analysis

“…This aspect of risk analysis for invasive plants has received less attention than has risk-assessment model development. Some surveys have been conducted on attitudes towards invasive plants (e.g., Andreau et al 2009;Bardsley and Edwards-Jones 2006;Bremer and Park 2007;Burt et al 2007;Colton and Alpert 1998;Daab and Flint 2010;García-Llorente et al 2008;Peters et al 2006), but similar efforts are lacking with respect to risk-assessment modeling and determining what stakeholders deem as acceptable risk. These previous surveys suggest that there are differences of opinion about invasive plants that could present challenges for the effective application of risk-assessment models.…”