Collected Evidence: Collected Evidence: Floating pennywort: Biological control using co-evolved, host specific herbivores A replicated laboratory and field study in South America found that the South American weevil caused more feeding lesions on floating pennywort than on any other plant species, but field results found that the weevil did not reduce floating pennywort biomass.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1123https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1123Tue, 13 Oct 2015 15:27:21 +0100Collected Evidence: Collected Evidence: Floating pennywort: Biological control using native herbivores No evidence was captured on biological control of floating pennywort using native herbivores. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1124https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1124Tue, 13 Oct 2015 15:28:43 +0100Collected Evidence: Collected Evidence: Floating pennywort: Biological control using fungal-based herbicides No evidence was captured on biological control of floating pennywort using fungal-based herbicides. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1125https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1125Tue, 13 Oct 2015 15:29:58 +0100Collected Evidence: Collected Evidence: Floating pennywort: Physical removal A study in Western Australia found that following a two-week program of physical removal of floating pennywort, the rate of growth exceeded the rate of removal. A study in the UK, found that removal using a mechanical digger and monthly picking by hand greatly reduced the cover of floating pennywort but did not completely eradicate it. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1126https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1126Tue, 13 Oct 2015 15:33:08 +0100Collected Evidence: Collected Evidence: Floating pennywort: Chemical control using herbicides 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. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1127https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1127Tue, 13 Oct 2015 15:36:51 +0100Collected Evidence: Collected Evidence: Floating pennywort: Combination treatment using herbicides and physical removal A before-and-after study in Western Australia found that a combination of cutting followed by glyphosate chemical treatment, removed floating pennywort. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1128https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1128Tue, 13 Oct 2015 15:39:22 +0100Collected Evidence: Collected Evidence: Floating pennywort: Use of hydrogen peroxide A controlled, replicated pilot study in The Netherlands, found that hydrogen peroxide sprayed on potted floating pennywort plants resulted in curling and transparency of the leaves when applied at the highest tested concentration (30%), but this was still not sufficient to kill the plant.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1129https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1129Tue, 13 Oct 2015 15:41:57 +0100Collected Evidence: Collected Evidence: Floating pennywort: Use of liquid nitrogen No evidence was captured on the use of liquid nitrogen for control of floating pennywort. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1130https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1130Tue, 13 Oct 2015 15:43:21 +0100Collected Evidence: Collected Evidence: Floating pennywort: Flame treatment A controlled, replicated, pilot experiment in 2010 in The Netherlands, found that flame treatments of 1, 2 or 3 seconds had a significantly negative and progressive impact on floating pennywort, and a 3 second repeat treatment after 11 days proved fatal. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1131https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1131Tue, 13 Oct 2015 15:46:00 +0100Collected Evidence: Collected Evidence: Floating pennywort: Excavation of banks No evidence was captured on the effects of excavation of banks using a sod-cutter or ‘turf-cutter’ to remove floating pennywort. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1132https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1132Tue, 13 Oct 2015 15:46:58 +0100Collected Evidence: Collected Evidence: Floating pennywort: Environmental control (e.g. shading, reduced flow, reduction of rooting depth, or dredging) No evidence was captured on the potential for environmental control of floating pennywort using shading, increased flow, reduction of rooting depth to below 1 metre, or dredging. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1133https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1133Tue, 13 Oct 2015 15:48:34 +0100Collected Evidence: Collected Evidence: Floating pennywort: Public education No evidence was captured on the impact of education programmes on control of floating pennywort. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1134https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1134Tue, 13 Oct 2015 15:49:48 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use hot water to control plants We found no evidence on the use of hot water to control Crassula helmsii. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1275https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1275Thu, 30 Jun 2016 08:21:56 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use hydrogen peroxide to control plants One controlled study in the UK using tank trials found that hydrogen peroxide did not control Crassula helmsii.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1281https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1281Tue, 12 Jul 2016 08:42:23 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use liquid nitrogen to kill plants We found no evidence for the effects of treating Crassula helmsii with liquid nitrogen. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1282https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1282Tue, 12 Jul 2016 08:51:36 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use hot foam to control plants One replicated, controlled study in the UK found that treatment with hot foam, along with other treatments, did not reduce cover of Crassula helmsii. One before-and-after study in the UK found that applying hot foam partially destroyed C. helmsii.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1286https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1286Tue, 12 Jul 2016 08:56:05 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use salt water to kill plants Two replicated, controlled container trials and two before-and-after field trials in the UK found that seawater eradicated Crassula helmsii.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1288https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1288Tue, 12 Jul 2016 09:14:42 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use flame-throwers to control plants We found no evidence on the use of flame-throwers to control Crassula helmsii. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1291https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1291Tue, 12 Jul 2016 09:26:14 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use dyes to reduce light levels One replicated, controlled study in the UK found that applying aquatic dye, along with other treatments, did not reduce coverage of Crassula helmsii. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1293https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1293Tue, 12 Jul 2016 09:32:38 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use lightproof barriers to control plants Five before-and-after studies in the UK found that covering Crassula helmsii with black sheeting or carpet strips eradicated or severely reduced the cover of the plant. However, C. helmsii was reported to have progressively recolonized two of the sites where it had been had initially been reported as eradicated.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1294https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1294Tue, 12 Jul 2016 09:39:41 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use grazing to control plants One of two replicated, controlled studies in the UK found that excluding grazing reduced the abundance and coverage of Crassula helmsii. The other study found no difference in cover of C. helmsii between ungrazed and grazed plots. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1301https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1301Tue, 12 Jul 2016 10:48:03 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Biological control using fungal-based herbicides We found no evidence for the effects of biological control of parrot’s feather using fungal-based herbicides. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1598https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1598Fri, 20 Oct 2017 14:56:08 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Biological control using herbivores One replicated, controlled laboratory study in Portugal found that grass carp did not reduce biomass or cover of parrot’s feather. Two replicated, randomized field studies in Argentina and the USA found that stocking with grass carp reduced the biomass or abundance of parrot’s feather. One field study in South Africa reported reduced growth of parrot’s feather following the release a South American leaf-feeding Lysathia. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1599https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1599Fri, 20 Oct 2017 14:58:11 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Biological control using plant pathogens One study in South Africa found that parrot’s feather plants survived after being treated with a strain of the bacterium Xanthomonas campestris. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1601https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1601Fri, 20 Oct 2017 15:05:32 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Decontamination / preventing further spread We found no evidence on the effects of decontamination to prevent further spread of parrot’s feather. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1602https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1602Fri, 20 Oct 2017 15:09:30 +0100
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What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

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