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Herbicide impacts on exotic grasses and a population of the critically endangered herb "Calystegia affinis" (Convolvulaceae) on Lord Howe Island

By Ian Hutton, Robert Coenraads, Tony D. Auld, Andrew J. Denham, M. K. J. Ooi and Dianne Brown


Introduced perennial grasses are capable of altering the habitat of native species, causing reductions in population size and vigour, and potentially affecting life-history processes such as survival, pollination and seedling recruitment. We examined the utility of herbicide treatment on two exotic grasses, Pennisetum clandestinum (Kikuyu) and Stenotaphrum secundatum (Buffalo grass) to restore the habitat of Calystegia affinis, a critically endangered species endemic to Lord Howe and Norfolk Islands. Using two herbicides, Asset (designed to affect only grasses) and Glyphosate (a general herbicide), we compared effectiveness in reducing grass cover on a population of Calystegia affinis. We protected Calystegia plants from the herbicides by ensuring their leaves were covered by plastic bags during herbicide application. Both herbicides were similarly effective in reducing grass cover after four weeks and had no noticeable adverse affect on Calystegia (suggesting the plastic bag protection was effective). After 26 weeks, Glyphosate was more effective in maintaining a reduced grass cover. Plots treated with either herbicide had a greater relative increase in abundance of Calystegia stems compared to untreated controls. The Glyphosate treatment resulted in the greatest relative increase in stem abundance, but this was not significantly greater than in the Asset treatment. We consider that spraying with Glyphosate treatment, with follow-up monitoring and spot-spraying, will assist the recovery of the Calystegia affinis population. Ultimately, the maintenance of a weed-free zone at the forest edge will provide suitable habitat for additional recruitment of this and other native species

Topics: ddc:580
Year: 2013
OAI identifier:

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  1. (2007). Available from URL: stenotaphrum_secundatum.htm. Accessed
  2. (1989). Biological invasion by Myrica faya in Hawai’i: Plant demography, nitrogen fixation, ecosystem effects.
  3. (1984). Biostatistical Analysis.
  4. (2005). Cattle grazing for Para Grass management in a mixed species wetland of north-eastern Australia.
  5. (1983). Census of vascular flora of Lord Howe Island.
  6. (2006). Control of Bulbil Watsonia (Watsonia meriana var. meriana) invading a banksia woodland: Effectiveness of 2,2– DPA and its impacts on native flora.
  7. (2002). Control of the exotic bulb, Yellow Soldier (Lachenalia reflexa) invading a Banksia woodland,
  8. (1984). Exotic plants on Lord Howe Island: distribution in space and time, 1853 –
  9. (2002). Final determination to list Calystegia affinis as an endangered species. Available from URL: Calystegia+affinis+a+twining+plant+endangered+species+listi ng.
  10. (2000). Genetic diversity and population structure of the serpentine endemic Calystegia collina (Convolvulaceae) in northern California.
  11. (2002). Herbicides, weeds and endangered species: management of bitou bush (Chrysanthemoides monilifera ssp rotundata) with glyphosate and impacts on the endangered shrub, Pimelea spicata.
  12. (2004). Impact of the invasive alien grass Melinis minutiflora at the savanna-forest ecotone in the Brazilian Cerrado.
  13. (1998). Impacts of biological invasions on disturbance regimes.
  14. (2005). Invasive plants can inhibit native tree seedlings: testing potential allelopathic mechanisms.
  15. (2005). Is there a relationship between herbaceous species richness and buffel grass (Cenchrus ciliaris)?
  16. (2000). Life span and biomass allocation of stunted black spruce clones in the subarctic environment.
  17. (2006). Limitations to seedling establishment in a mesic Hawaiian forest.
  18. (2006). Long-distance seed dispersal, clone longevity and lack of phylogeographical structure in the European distributional range of the coastal Calystegia soldanella
  19. (2007). Lord Howe Island Biodiversity Management Plan. Department of Environment & Climate Change,
  20. (2006). Mechanisms of exclusion of native coastal marsh plants by an invasive grass.
  21. (1960). Plant communities of the Mokohinau Islands, northern N.Z.
  22. (2004). Rare plant surveys Lord Howe Island 2.
  23. (2001). Rare plant surveys Lord Howe Island. Unpublished report to NSW Scientific Committee.
  24. (1999). Report on survey of Calystegia affinis on Lord Howe Island. Unpublished report to Lord Howe Island Board.
  25. (1995). Solution to weed problems in urban bushland. In: Conserving biodiversity: Threats and Solutions
  26. (1981). Techniques of analysis of variance in experimental marine biology and ecology.
  27. (2000). The determination of weeds of national significance. National Weeds Strategy Executive Committee,
  28. (2004). The role of alien plants in the natural coastal vegetation in central-northern Spain.
  29. (1995). The threat of environmental weeds to biodiversity in Australia: a search for solutions. In: Conserving Biodiversity: Threats and Solutions
  30. (1977). The world’s worst weeds: distribution and biology. East-West Center/University Press of Hawaii,
  31. (1992). Threatened Australian plants: Overview and case studies.
  32. (1999). Variation of breeding system, floral rewards, and reproductive success in clonal Calystegia species (Convolvulaceae).
  33. (1983). Vegetation of Lord Howe Island.

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