The Foliar Browse Index method uses ground-based assessment of permanently marked plant indicator species to determine the impact of possums on forest trees/mistletoes and their response to possum control.
Possum control in New Zealand is necessary to protect the biodiversity of native forests and other communities. Measuring the results and outcomes of this work is an important aspect of control programmes and helps managers plan and determine the efficacy of their work.
The Foliar Browse Index (FBI) method uses ground-based assessment of permanently marked plant indicator species to determine the impact of possums on forest trees/mistletoes and their response to possum control. It has been used extensively around New Zealand since its development in the late 1990s.
This updated field manual incorporates changes and improvements to the method based on the knowledge that has been gained over the last decade.
- Designing a survey to monitor possum damage to vegetation
- Choice of indicator species
- Sampling design
- Locating transects, plots and selecting sample trees
- Sample size
- Sampling time and re-measurement frequency
- The Foliar Browse Index method
- Transect data
- Plot data
- Assessment of indicator species
- Large-leaved mistletoes
- Reassessment of indicator species
- Technical considerations and tips
- Data analysis and storage
- Appendix 1 FBI indicator species assessment sheet
- Appendix 2 Suitability of indicator species that have been used in FBI assessments
and their attributes
- Appendix 3 Examples of possum browse on a range of indicator species
- Appendix 4 FBI work flow chart
- Appendix 5 List of equipment required for establishing or re-measuring
- Appendix 6A FBI transect and plot data sheet
- Appendix 6B FBI indicator species data sheet
- Appendix 6C FBI mistletoe data sheet
- Appendix 7 Foliage cover scale
- Appendix 8 Observer calibration exercise
This field manual has been produced by the Department of Conservation and updates the original document: Payton, I.J.; Pekelharing, C.J.; Frampton, C.M. 1999: A Foliar Browse Index: a method for monitoring possum (Trichosurus vulpecula) damage to plant species and forest communities. Manaaki Whenua Landcare Research, Lincoln, New Zealand.