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Providing evidence to improve practice

Action: Crassula helmsii: Use hydrogen peroxide to control plants Control of Freshwater Invasive Species

Key messages

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  • One controlled study in the UK using tank trials found that hydrogen peroxide did not control Crassula helmsii.


Supporting evidence from individual studies


A controlled tank trial in 1988-1989 in southern England, UK (Dawson & Henville 1991) reported that hydrogen peroxide did not reduce the biomass of C. helmsii, although no statistical tests were carried out. Tank trials using low concentrations of hydrogen peroxide did not reduce the mass of emergent or submerged C. helmsii (data not given). Treatment with a higher concentration of hydrogen peroxide led to a 24% reduction in emergent vegetation, but a 45% increase in submerged vegetation compared to a control. C. helmsii was grown either in deep water as submerged plants, or in shallow water as emergent plants, in 300 l tanks. In low concentration trials hydrogen peroxide was applied to submerged and emergent vegetation at 20 g/m2 or 100 g/m2 in autumn 1988. High concentration trials used 250 g/m2 in spring 1989. Final biomass was measured after ten weeks.


Referenced papers

Please cite as:

Aldridge, D., Ockendon, N., Rocha, R., Smith, R.K. & Sutherland, W.J. (2019) Some aspects of control of freshwater invasive species. Pages 569-602 in: W.J. Sutherland, L.V. Dicks, N. Ockendon, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2019. Open Book Publishers, Cambridge, UK.