Floating pennywort: Chemical control using herbicides

How is the evidence assessed?
  • Effectiveness
  • Certainty
  • Harms
    not assessed

Study locations

Key messages

  • A controlled, replicated study in the UK found that the herbicide 2,4-D amine applied at 4.2 kg/ha achieved near to 100% mortality, compared with the herbicide glyphosate applied at 2.2 kg active ingredient/ha (without an adjuvant) which achieved  negligible mortality.

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 controlled, replicated field experiment in 1997 in the Addlestone Bourne flood relief channel England, UK (Newman & Dawson 1999) found that the herbicide 2,4-D amine achieved near to 100% mortality, compared with the herbicide glyphosate which achieved  negligible mortality. The chemical 2,4-D amine applied at 4.2 kg/ha achieved 76% decrease in floating pennywort Hydrocotyle ranunculoides biomass and almost 100% mortality over the first four weeks of treatment.  In comparison, treatment with glyphosate applied at 2.2 kg/ha (without an adjuvant) resulted in a 20% decrease in biomass over the first four weeks and negligible mortality.  Two trial plots in a 65m section of the channel were marked out and subdivided into six treatment blocks.  Two blocks were sprayed in 2,4-D amine, two in glyphosate, and two were left untreated in control plots. Wet weight of root and shoot material/m2 was taken before treatment, and each week after treatment for four weeks following herbicide application. Percentage cover measurements were made each week until nine weeks after spraying.

    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

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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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