Biological Invasions

, Volume 19, Issue 3, pp 925–937 | Cite as

Aliens in the nursery: assessing the attitudes of nursery managers to invasive species regulations

  • Kate CroninEmail author
  • Haylee Kaplan
  • Mirijam Gaertner
  • Ulrike M. Irlich
  • M. Timm Hoffman
Original Paper


The horticultural industry is recognised as a major pathway for the introduction and spread of invasive alien plants (IAPs). The Conservation of Agricultural Resources Act (CARA) of 1983 (Act No. 43 of 1983) listed and categorised invasive species with an aim to curb their spread. The more recently enacted Alien and Invasive Species Regulations under South Africa’s National Environmental Management: Biodiversity Act (NEMBA) are intended, in part, to improve controls on the horticultural industry’s role in the spread of IAPs. In order to assess, and enhance, the likely effectiveness of NEMBA, it is important to build an understanding of stakeholders’ awareness and attitudes towards the control of IAPs and associated regulatory policies. A two-pronged approach—involving nursery manager interviews (n = 30) and plant stock audit assessments (n = 41)—was used to gauge the awareness, compliance and attitudes of nursery managers towards both the CARA and NEMBA invasive species regulations. Less than ten percent of audited nurseries were fully compliant with the NEMBA regulations, and over 50% were stocking IAPs that have been regulated for at least 13 years under CARA. This is despite high levels of awareness (70%) about the CARA regulations reported in the interviews. The majority (73.5%) of IAP species stocked in nurseries were NEMBA category 1b invaders such as Nerium oleander and Canna indica. These are widespread and well-established invaders that require compulsory control under NEMBA. Half of the managers were not aware that the NEMBA regulations had been promulgated, but most respondents nevertheless reported being enthusiastic about compliance. Several factors were quoted as constraints on compliance by the industry. These included a perceived lack of enforcement, weak communication from government, and the lack of inclusion of the industry in the regulatory process. Suggested interventions that could enhance the impact of IAP regulations will involve improving the user-friendliness of the regulations, and supplementing the current top-down approach to regulation with an inclusive partner-centred approach.


Compliance Invasive species Legislation Ornamental horticulture Perceptions 



The authors are grateful to the following people for their assistance and support: Katya Mauff for statistical assistance; Ariella Rink and Lukas Otto for assistance with data collection; Ana Novoa, Guy Preston and Kay Montgomery for advice and insight with the project design; and Ernita Van Wyk for useful comments on the manuscript. HK acknowledges support from the Working for Water (WfW) Programme of the South African Department of Environmental Affairs, through the South African National Biodiversity Institute Invasive Species Programme. Lastly, we thank the nursery managers who agreed to participate in this study and took the time to respond to the questionnaire.

Compliance with ethical standards

This research was approved by the University of Cape Town Faculty of Science’s Research Ethics Committee (7 October 2014, FSREC 074).

Conflict of interest

The authors declare that they have no conflict of interest.

Informed consent

Prior to being interviewed, participants were provided with an informed consent letter, detailing the content of the interview, how the information would be used and assurances that strict confidentiality would be preserved.

Supplementary material

10530_2016_1363_MOESM1_ESM.pdf (349 kb)
Online resource 1 Questionnaire used during interviews with nursery managers (PDF 348 kb)


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Copyright information

© Springer International Publishing Switzerland 2017

Authors and Affiliations

  1. 1.Department of Biological Sciences, Percy FitzPatrick InstituteUniversity of Cape TownCape TownSouth Africa
  2. 2.Invasive Species Programme, South African National Biodiversity InstituteKirstenbosch Research CentreClaremontSouth Africa
  3. 3.Department of Botany and Zoology, Centre for Invasion BiologyStellenbosch UniversityMatielandSouth Africa
  4. 4.Green Jobs UnitEnvironmental Resource Management Department (ERMD)Cape TownSouth Africa
  5. 5.Plant Conservation Unit, Department of Biological SciencesUniversity of Cape TownCape TownSouth Africa

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