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Providing evidence to improve practice

Individual study: Controlling New Zealand pygmyweed Crassula helmsii using hot foam, herbicide and by burying at Old Moor RSPB Reserve, South Yorkshire, England

Published source details

Bridge T. (2005) Controlling New Zealand pygmyweed Crassula helmsii using hot foam, herbicide and by burying at Old Moor RSPB Reserve, South Yorkshire, England. Conservation Evidence, 2, 33-34


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Crassula helmsii: Use lightproof barriers to control plants Control of Freshwater Invasive Species

A before-and-after field trial in 2003 at waterbodies in a nature reserve in South Yorkshire, UK (Bridge 2005) reported that covering C. helmsii with black plastic and soil killed all plants, although no statistical tests were carried out. C. helmsii was covered with black plastic and topped with 1 m of soil in March 2003. No details about the area covered, duration of treatment or subsequent monitoring was provided.

 

Crassula helmsii: Use hot foam to control plants Control of Freshwater Invasive Species

A before-and-after study in 2003 at waterbodies in a nature reserve in South Yorkshire, UK (Bridge 2005) reported that spraying with hot foam partially destroyed C. helmsii, although statistical tests were not carried out.  Approximately 50% of C. helmsii was killed by the treatment, but only the top layers of the plant were affected. Biodegradable ‘Waipuna’ hot foam, an organic compound of corn and coconut sugars, was sprayed three times between September and November 2003. No information about the size of area treated or monitoring was provided.

 

Crassula helmsii: Chemical control using herbicides Control of Freshwater Invasive Species

A before-and-after field trial in 2004 at a single waterbody in a nature reserve in South Yorkshire, UK (Bridge 2005) reported that treating C. helmsii with glyphosate-based herbicide partially destroyed the plants, although no statistical tests were carried out.  Spraying with glyphosate killed approximately 50% of C. helmsii, but did not eradicate it. Glyphos biactive was sprayed on exposed plants in a shallow pond at 5 l/ha in July-August 2004. No details of the size of area treated or monitoring were provided.