Collected 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: Alter environmental conditions to control plants No evidence was captured on altering environmental conditions to control Crassula helmsii by using shading, increasing turbidity, re-shaping or re-profiling banks of waterbodies 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%2F1296https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1296Tue, 12 Jul 2016 10:38:54 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Plant other species to suppress growth We found no evidence for the effects of using other plant species to control growth of 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%2F1299https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1299Tue, 12 Jul 2016 10:42:46 +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: Crassula helmsii: Dry out waterbodies to control plants We found no evidence for the effects of draining waterbodies on 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%2F1303https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1303Tue, 12 Jul 2016 10:51:10 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Bury plants We found no evidence on the use of burying with soil alone 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%2F1305https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1305Tue, 12 Jul 2016 10:53:24 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Surround with wire mesh We found no evidence that surrounding Crassula helmsii with wire mesh reduced its rate of spread. '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%2F1307https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1307Tue, 12 Jul 2016 10:54:59 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Decontamination to prevent further spread One controlled, replicated container study in the UK found that submerging Crassula helmsii in hot water led to higher mortality than drying out plant fragments or a control.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1308https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1308Tue, 12 Jul 2016 10:57:56 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Public education No evidence was captured on the impact of education programmes on control of 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%2F1311https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1311Tue, 12 Jul 2016 11:01:15 +0100Collected Evidence: Collected Evidence: Crassula helmsii: Use a combination of control measures One before-and-after study at a single pond in the UK found covering Crassula helmsii with carpet, followed by treatment with the herbicide glyphosate, killed 80% of the plant. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1313https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1313Tue, 12 Jul 2016 11:04:35 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Mechanical harvesting and cutting We found no evidence on the use of manual harvesting to control 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%2F1568https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1568Fri, 20 Oct 2017 11:31:24 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Mechanical excavation We found no evidence on the use of mechanical excavation to control 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%2F1570https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1570Fri, 20 Oct 2017 11:44:58 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Removal using water jets We found no evidence on the use of water jets to control 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%2F1572https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1572Fri, 20 Oct 2017 12:26:00 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Suction dredging and diver-assisted suction removal We found no evidence on the use of suction dredging and diver-assisted suction removal to control 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%2F1573https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1573Fri, 20 Oct 2017 12:27:56 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Manual harvesting (hand-weeding) We found no evidence on the effects of manual to control 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%2F1575https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1575Fri, 20 Oct 2017 12:31:39 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Use of lightproof barriers We found no evidence on the use of lightproof barriers to control 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%2F1576https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1576Fri, 20 Oct 2017 12:32:56 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Water level drawdown One replicated, randomized, controlled laboratory study in the USA found that water removal to expose plants to drying during the summer led to lower survival of parrot’s feather plants than exposing plants to drying during the winter. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1585https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1585Fri, 20 Oct 2017 13:07:37 +0100Collected Evidence: Collected Evidence: Parrot’s feather: Dye application We found no evidence on the use of dye treatments to control 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%2F1587https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1587Fri, 20 Oct 2017 13:10:23 +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 +0100
What Works 2021 cover

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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