Collected Evidence: Collected Evidence: Control problematic plants (specific intervention unclear): freshwater marshes or swamps One study evaluated the effects, on vegetation, of controlling problematic plants in freshwater marshes or swamps using unspecified or unclear methods. The study was in the USA. VEGETATION COMMUNITY Overall richness/diversity (1 study): One replicated, site comparison study in the USA found that marshes in which non-native plants were actively controlled had higher overall plant richness and diversity, after three years, than marshes in which non-native plants were not controlled. VEGETATION ABUNDANCE Overall abundance (1 study): One replicated, site comparison study in the USA found that marshes in which non-native plants were actively controlled had similar overall vegetation cover, after three years, to marshes in which non-native plants were not controlled. Individual species abundance (1 study): One study quantified the effect of this action on the abundance of individual plant species, other than those being controlled. The replicated, site comparison study in the USA found, for example, that spikerush Eleocharis cover was greater in marshes where non-native plants were actively controlled than where they were not controlled. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3083https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3083Fri, 02 Apr 2021 17:04:16 +0100Collected Evidence: Collected Evidence: Control problematic plants (specific intervention unclear): brackish/saline marshes or swamps One study evaluated the effects, on vegetation, of controlling problematic plants in brackish/saline marshes or swamps using unspecified or unclear methods. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Overall abundance (1 study): One replicated, site comparison study in salt marshes in the USA found that plots in which common reed Phragmites australis had been controlled 4–10 years previously contained a similar density of plant stems to nearby natural marshes Individual species abundance (1 study): One study quantified the effect of this action on the abundance of individual plant species, other than those being controlled. The replicated, site comparison study in salt marshes in the USA found that plots in which common reed Phragmites australis had been controlled 4–10 years previously had similar cover of saltmarsh cordgrass Spartina patens to nearby natural marshes. VEGETATION STRUCTURE Height (1 study): One replicated, site comparison study in salt marshes in the USA found that plots in which common reed Phragmites australis had been controlled 4–10 years previously contained vegetation of similar height to nearby natural marshes. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3084https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3084Fri, 02 Apr 2021 17:04:33 +0100Collected Evidence: Collected Evidence: Control problematic plants (multiple interventions): brackish/saline marshes or swampsWe found no studies that evaluated the effects, on vegetation, of controlling problematic plants in brackish/saline marshes or swamps using >3 combined interventions.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3088https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3088Sat, 03 Apr 2021 14:52:44 +0100Collected Evidence: Collected Evidence: Physically remove problematic plants: freshwater swampsWe found no studies that evaluated the effects, on vegetation, of physically removing problematic plants from freshwater swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3093https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3093Sat, 03 Apr 2021 15:00:05 +0100Collected Evidence: Collected Evidence: Physically remove problematic plants: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of physically removing problematic plants from brackish/saline swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3094https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3094Sat, 03 Apr 2021 15:00:18 +0100Collected Evidence: Collected Evidence: Physically damage problematic plants: brackish/salt marshesWe found no studies that evaluated the effects, on vegetation, of physically damaging problematic plants in brackish/salt marshes.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3096https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3096Sat, 03 Apr 2021 16:05:40 +0100Collected Evidence: Collected Evidence: Physically damage problematic plants: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of physically damaging problematic plants in brackish/saline swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3098https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3098Sat, 03 Apr 2021 16:06:14 +0100Collected Evidence: Collected Evidence: Manage water level to control problematic plantsWe found no studies that evaluated the effects, on vegetation, of managing water levels to control problematic plants in marshes or swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3099https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3099Sun, 04 Apr 2021 09:18:38 +0100Collected Evidence: Collected Evidence: Add salt to control problematic plants: freshwater marshesWe found no studies that evaluated the effects, on vegetation, of directly adding salt to control problematic plants in freshwater marshes.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3100https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3100Sun, 04 Apr 2021 09:24:05 +0100Collected Evidence: Collected Evidence: Add salt to control problematic plants: freshwater swampsWe found no studies that evaluated the effects, on vegetation, of directly adding salt to control problematic plants in freshwater swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3102https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3102Sun, 04 Apr 2021 09:25:07 +0100Collected Evidence: Collected Evidence: Add salt to control problematic plants: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of directly adding salt to control problematic plants in brackish/saline swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3103https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3103Sun, 04 Apr 2021 09:25:17 +0100Collected Evidence: Collected Evidence: Use cutting/mowing to control problematic herbaceous plants: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of cutting/mowing problematic herbaceous plants or small shrubs in brackish/saline swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3107https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3107Sun, 04 Apr 2021 10:00:38 +0100Collected Evidence: Collected Evidence: Use cutting to control problematic large trees/shrubs: freshwater swampsWe found no studies that evaluated the effects, on vegetation, of cutting down problematic large trees/shrubs in freshwater swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3110https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3110Sun, 04 Apr 2021 14:32:24 +0100Collected Evidence: Collected Evidence: Use cutting to control problematic large trees/shrubs: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of cutting down problematic large trees/shrubs in brackish/saline swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3111https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3111Sun, 04 Apr 2021 14:32:37 +0100Collected Evidence: Collected Evidence: Use grazing to control problematic plants: brackish/salt marshesWe found no studies that evaluated the effects, on vegetation, of using grazing to control problematic plants in brackish/salt marshes.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3113https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3113Sun, 04 Apr 2021 15:42:40 +0100Collected Evidence: Collected Evidence: Use grazing to control problematic plants: freshwater swampsWe found no studies that evaluated the effects, on vegetation, of using grazing to control problematic plants in freshwater swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3114https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3114Sun, 04 Apr 2021 15:47:05 +0100Collected Evidence: Collected Evidence: Use grazing to control problematic plants: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of using grazing to control problematic plants in brackish/saline swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3115https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3115Sun, 04 Apr 2021 15:47:21 +0100Collected Evidence: Collected Evidence: Use prescribed fire to control problematic plants: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of using prescribed fire to control problematic plants in brackish/saline swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3119https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3119Sun, 04 Apr 2021 16:05:37 +0100Collected Evidence: Collected Evidence: Use herbicide to control problematic plants: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of using herbicide to control problematic plants in brackish/saline swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3123https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3123Sun, 04 Apr 2021 17:19:48 +0100Collected Evidence: Collected Evidence: Use covers/barriers to control problematic plants: brackish/salt marshesWe found no studies that evaluated the effects, on vegetation, of using covers or barriers to control problematic plants in brackish/salt marshes.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3125https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3125Mon, 05 Apr 2021 09:58:54 +0100Collected Evidence: Collected Evidence: Use covers/barriers to control problematic plants: freshwater swampsWe found no studies that evaluated the effects, on vegetation, of using covers or barriers to control problematic plants in freshwater swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3126https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3126Mon, 05 Apr 2021 09:59:05 +0100Collected Evidence: Collected Evidence: Use covers/barriers to control problematic plants: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of using covers or barriers to control problematic plants in brackish/saline swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3127https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3127Mon, 05 Apr 2021 09:59:17 +0100Collected Evidence: Collected Evidence: Introduce organisms to control problematic plants: brackish/salt marshesWe found no studies that evaluated the effects, on vegetation, of introducing organisms (other than large vertebrate grazers) to control problematic plants in brackish/salt marshes.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3129https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3129Mon, 05 Apr 2021 11:56:07 +0100Collected Evidence: Collected Evidence: Introduce organisms to control problematic plants: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of introducing organisms (other than large vertebrate grazers) to control problematic plants in brackish/saline swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3131https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3131Mon, 05 Apr 2021 11:56:34 +0100Collected Evidence: Collected Evidence: Control populations of wild vertebrates: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of controlling populations of wild vertebrates in brackish/saline swamps.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated 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%2Fconservationevidencejournal.com%2Factions%2F3139https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3139Mon, 05 Apr 2021 14:10:25 +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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