Floating pennywort: Combination treatment using herbicides and physical removal

How is the evidence assessed?
  • Effectiveness
    70%
  • Certainty
    35%
  • Harms
    not assessed

Source countries

Key messages

  • A before-and-after study in Western Australia found that a combination of cutting followed by glyphosate chemical treatment, removed floating pennywort.

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A before-and-after study from 1993 to 1994 in a river in Western Australia (Ruiz-Avila & Klemm 1996) found that a combination of cutting followed by glyphosate chemical treatment, removed approximately 2,000 tonnes of floating pennywort Hydrocotyle ranunculoides.  Floating pennywort mats were cut with sickles from small boats. The boats pushed mats to a conveyor harvester and mats were then floated to the bank, where they were removed. After most of the weed had been removed, the chemical glyphosate (Tradename Roundup) was applied along the banks at a rate of 360 g/ha of active ingredient in 1993 and 450 g/ha in 1994. The amount of floating pennywort removed was estimated from the number of truckloads. The area was monitored to assess re-infestation of floating pennywort and assess water quality.  No further details were available.

    Study and other actions tested
Please cite as:

Aldridge, D., Ockendon, N., Rocha, R., Smith, R.K. & Sutherland, W.J. (2020) Some Aspects of Control of Freshwater Invasive Species. Pages 555-87 in: W.J. Sutherland, L.V. Dicks, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2020. Open Book Publishers, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

Control of Freshwater Invasive Species

This Action forms part of the Action Synopsis:

Control of Freshwater Invasive Species
Control of Freshwater Invasive Species

Control of Freshwater Invasive Species - Published 2017

Control of Freshwater Invasive Species Synopsis

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