Collected Evidence: Collected Evidence: Use fences or barriers to protect brackish/saline wetlands planted with non-woody plantsWe found no studies that evaluated the effects, on vegetation, of using fences or barriers to protect brackish/saline wetlands planted with emergent, non-woody plants.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3329https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3329Sun, 11 Apr 2021 13:14:53 +0100Collected Evidence: Collected Evidence: Use fences or barriers to protect freshwater wetlands planted with trees/shrubs Five studies evaluated the effects, on vegetation, of using fences or barriers to protect freshwater wetlands planted with trees/shrubs. Four studies were in the USA and one was in Australia. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Tree/shrub abundance (1 study): One replicated, paired, controlled study in a floodplain swamp clearing in the USA found that amongst plots sown with tree seeds, fencing to exclude deer had no significant effect on total tree seedling density after three years. VEGETATION STRUCTURE Height (2 studies): One replicated, paired, controlled study in a floodplain swamp clearing in the USA found that amongst plots sown with tree seeds, those also fenced to exclude deer contained taller tree seedlings, after three years, than those left unfenced. One replicated, paired, controlled study in created freshwater wetlands in the USA found that the average height of white cedar Thuja occidentalis saplings typically increased by a similar amount, between two and five years after planting, in plots fenced to exclude deer and plots left unfenced. OTHER Survival (3 studies): One replicated, paired, controlled study in floodplain swamps in Australia reported that planted swamp gum Eucalyptus camphora seedlings had a much higher survival rate, over one year, in plots fenced to exclude mammals than in open plots. Two replicated, paired, controlled studies in freshwater wetlands in the USA reported that exclusion fencing sometimes increased survival of planted tree seedlings but sometimes had no clear or significant effect. This depended on factors such as the season of planting, seedling elevation, and site. Growth (1 study): One replicated, randomized, controlled study in a nutria-invaded wetland in the USA found that planted baldcypress Taxodium distichum seedlings grew more, over one growing season, when protected than when left unprotected. Plastic guards increased height and diameter growth rates. Sticky, insect-repellent oil increased the growth rate for height, but not diameter. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3330https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3330Sun, 11 Apr 2021 13:15:05 +0100Collected Evidence: Collected Evidence: Use fences or barriers to protect planted brackish/saline wetlands planted with trees/shrubs One study evaluated the effects, on vegetation, of using fences or barriers to protect brackish/saline wetlands planted with trees/shrubs. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE Height (1 study): One replicated, paired, controlled study in exposed coastal sites in the USA found that red mangrove Rhizophora mangle propagules planted within full-length plastic shelters had grown taller than propagules planted without shelter in three of four comparisons, made 22–129 days after planting. OTHER Survival (1 study): One replicated, paired, controlled study in exposed coastal sites in the USA reported that full-length plastic shelters increased the survival rate of planted red mangrove Rhizophora mangle propagules over 4–8 months, but that full-length bamboo shelters and below-ground plastic shelters had no clear effect on survival. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3331https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3331Sun, 11 Apr 2021 13:15:17 +0100Collected Evidence: Collected Evidence: Remove vegetation that could compete with planted non-woody plants: freshwater wetlands Three studies evaluated the effects, on emergent non-woody vegetation planted in freshwater wetlands, of removing competing plants. All three studies were in the USA. Two studies used the same experimental wet basins but planted different species. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Herb abundance (1 study): One replicated, randomized, paired, controlled study in wet meadows in the USA found removing an invasive species with herbicide before sowing mixed grass and forb seeds increased the total biomass of sown species after 1–2 growing seasons, but that burning to remove the invasive species had no significant effect on sown species biomass. Individual species abundance (1 study): One replicated, paired, controlled study in wet basins in the USA found that the effect of weeding to remove competitors on lake sedge Carex lacustris biomass and density, in the three years after planting, depended on the year and water level. VEGETATION STRUCTURE Height (2 studies): Two replicated, paired, controlled studies in wet basins in the USA examined the effect of weeding to remove competitors on the height of planted sedges. One of the studies found that weeding had no significant effect on the height of planted tussock sedge Carex stricta in three of three years. The other study found that weeding reduced the average height of lake sedge Carex lacustris in the first year after planting, but had no significant effect in the following two years. OTHER Survival (2 studies): Two replicated, paired, controlled studies in wet basins in the USA examined the effect of weeding to remove competitors on the survival of planted sedges Carex spp. Both studies found that weeding had no significant effect on sedge survival in at least two of three years. One of the studies found that weeding affected tussock sedge Carex stricta survival in the second year after planting, but that the direction of the effect depended on plot elevation. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3332https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3332Sun, 11 Apr 2021 14:05:56 +0100Collected Evidence: Collected Evidence: Remove vegetation that could compete with planted non-woody plants: brackish/saline wetlands One study evaluated the effects, on emergent non-woody vegetation planted in brackish/saline wetlands, of removing competing plants. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER Germination/emergence (1 study): One replicated, randomized, paired, controlled study in an estuarine salt marsh in the USA found that thinning cover of the dominant plant before sowing dwarf saltwort Salicornia bigelovii seeds had no significant effect on saltwort seedling density, over the following two months. Survival (1 study): The same study found that thinning the dominant plant increased the survival rate of dwarf saltwort Salicornia bigelovii transplants over the first six months after planting. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3333https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3333Sun, 11 Apr 2021 14:08:52 +0100Collected Evidence: Collected Evidence: Remove vegetation that could compete with planted trees/shrubs: freshwater wetlands Five studies evaluated the effects, on trees/shrubs planted in freshwater wetlands, of removing competing plants. Four studies were in the USA. Two of these took place in the same swamp, but with different experimental set-ups. One study was in Australia. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE Height (3 studies): Three replicated, controlled studies (two also randomized, two also paired) in a wet meadow in Australia and a degraded swamp in the USA found that clearing vegetation before planting tree/shrub seedlings typically had no clear or significant effect on their height, after 1–4 growing seasons. However, one of the studies in the USA found that planted baldcypress Taxodium distichum seedlings were taller, after three growing seasons, when planted amongst cut woody vegetation than below an uncleared canopy. Diameter/perimeter/area (1 study): One replicated, randomized, paired, controlled study in a wet meadow in Australia found that clearing vegetation, before planting tree/shrub seedlings, typically had no significant effect on the diameter of these seedlings nine months later. OTHER Germination/emergence (1 study): One replicated, randomized, paired, controlled study in a wet meadow in Australia found that there were more seedlings in plots that had been cleared of vegetation before sowing tree/shrub seeds, than in plots that had not been cleared before sowing. Seedlings were counted two months after sowing. Survival (4 studies): Three replicated, controlled studies (two also randomized, two also paired) in a wet meadow in Australia and a degraded swamp in the USA found that clearing vegetation before planting tree/shrub seedlings typically had no clear or significant effect on their survival, after 1–4 growing seasons. However, one of the studies in the USA found that planted baldcypress Taxodium distichum seedlings had a lower survival rate, after three growing seasons, when planted amongst cut woody vegetation than below an uncleared canopy. One replicated, randomized, paired, controlled study in degraded swamps in the USA found that removing reed canarygrass Phalaris arundinacea before planting tree/shrub seedlings never significantly reduced their survival rate over 1–2 growing seasons, and often increased it. Growth (1 study): One replicated, randomized, controlled study in the USA found that baldcypress Taxodium distichum seedlings planted into a marsh grew more in diameter, but less in height, when planted into plots cleared of vines than when planted into uncleared plots. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3334https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3334Sun, 11 Apr 2021 14:09:05 +0100Collected Evidence: Collected Evidence: Remove vegetation that could compete with planted trees/shrubs: brackish/saline wetlandsWe found no studies that evaluated the effects, on trees/shrubs planted in brackish/saline wetlands, of removing competing plants.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3335https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3335Sun, 11 Apr 2021 14:09:29 +0100Collected Evidence: Collected Evidence: Install physical supports for planted non-woody plants: freshwater wetlands One study evaluated the effects of installing physical supports for emergent, non-woody plants planted in freshwater wetlands. The study was in the Netherlands. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE Biomass/plant (1 study): One replicated, controlled study at the edge of a freshwater lake in the Netherlands found that supporting planted bulrushes Scirpus with wire mesh had no significant effect on biomass of individual plants after 1–2 years. Stems/plant (1 study): The same study found that supporting planted bulrushes Scirpus with wire mesh had no significant effect on number of shoots/plant after 1–2 years. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3336https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3336Sun, 11 Apr 2021 16:38:18 +0100Collected Evidence: Collected Evidence: Install physical supports for planted non-woody plants: brackish/saline wetlandsWe found no studies that evaluated the effects of installing physical supports for emergent, non-woody plants planted in brackish/saline wetlands.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3337https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3337Sun, 11 Apr 2021 16:38:28 +0100Collected Evidence: Collected Evidence: Install physical supports for planted trees/shrubs: freshwater wetlandsWe found no studies that evaluated the effects of installing physical supports for trees/shrubs planted in freshwater wetlands.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3338https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3338Sun, 11 Apr 2021 16:38:46 +0100Collected Evidence: Collected Evidence: Install physical supports for planted trees/shrubs: brackish/saline wetlandsWe found no studies that evaluated the effects of installing physical supports for trees/shrubs planted in brackish/saline wetlands.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3339https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3339Sun, 11 Apr 2021 16:39:01 +0100Collected Evidence: Collected Evidence: Use flotation devices to support planted vegetationWe found no studies that evaluated the effects of using flotation devices to support emergent vegetation planted in wetlands.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3340https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3340Sun, 11 Apr 2021 16:45:23 +0100Collected Evidence: Collected Evidence: Plant non-woody plants into moisture-retaining peat pots: freshwater wetlands One study evaluated the effects of using moisture-retaining peat pots when planting emergent, non-woody vegetation in freshwater wetlands. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Individual species abundance (1 study): One replicated, randomized, paired, controlled study in a wetland in the USA found that tussock sedge Carex stricta cover was similar across plots, after two growing seasons, whether sedges were planted into peat pots or into existing wetland soil. VEGETATION STRUCTURE Individual plant size (1 study): One replicated, randomized, paired, controlled study in a wetland in the USA found that the biomass of tussock sedge Carex stricta plants was similar, after two growing seasons, whether they were planted into peat pots or into existing wetland soil. OTHER Survival (1 study): One replicated, randomized, paired, controlled study in a wetland in the USA found that the survival rate of tussock sedge Carex stricta plants was similar, after two growing seasons, whether they were planted into peat pots or into existing wetland soil. Growth (1 study): The same study found that the growth rate of tussock sedge Carex stricta was typically similar, over two growing seasons, when planted into peat pots or into existing wetland soil. However, in a dry area and in a dry year, planting in peat pots did increase the growth rate. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3341https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3341Sun, 11 Apr 2021 16:45:47 +0100Collected Evidence: Collected Evidence: Plant non-woody plants into moisture-retaining peat pots: brackish/saline wetlandsWe found no studies that evaluated the effects of using moisture-retaining peat pots when planting emergent, non-woody vegetation in brackish/saline wetlands.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3342https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3342Sun, 11 Apr 2021 16:46:08 +0100Collected Evidence: Collected Evidence: Plant trees/shrubs into moisture-retaining peat pots: freshwater wetlandsWe found no studies that evaluated the effects of using moisture-retaining peat pots when planting trees/shrubs in freshwater wetlands.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3343https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3343Sun, 11 Apr 2021 16:46:17 +0100Collected Evidence: Collected Evidence: Plant trees/shrubs into moisture-retaining peat pots: brackish/saline wetlandsWe found no studies that evaluated the effects of using moisture-retaining peat pots when planting trees/shrubs in brackish/saline wetlands.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3344https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3344Sun, 11 Apr 2021 16:46:35 +0100Collected Evidence: Collected Evidence: Plant vegetation into heavy containersWe found no studies that evaluated the effects of planting emergent wetland vegetation into heavy containers.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3345https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3345Sun, 11 Apr 2021 16:55:25 +0100Collected Evidence: Collected Evidence: Allow plants to adjust to field conditions before plantingWe found no studies that evaluated the effects of allowing emergent vegetation to adjust to field conditions before planting in wetlands.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3349https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3349Sun, 11 Apr 2021 16:56:48 +0100Collected Evidence: Collected Evidence: Add root-associated fungi to plants before plantingWe found no studies that evaluated the effects – on emergent wetland plants – of adding root-associated fungi before planting.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3350https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3350Sun, 11 Apr 2021 16:59:38 +0100Collected Evidence: Collected Evidence: Apply root dip to non-woody plants before planting: freshwater wetlandsWe found no studies that evaluated the effects – on emergent, non-woody plants typical of freshwater wetlands – of applying a non-fungal root dip before planting.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3351https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3351Sun, 11 Apr 2021 17:12:52 +0100Collected Evidence: Collected Evidence: Apply root dip to non-woody plants before planting: brackish/saline wetlands One study evaluated the effects – on emergent, non-woody plants typical of brackish/saline wetlands – of applying a non-fungal root dip before planting. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Individual species abundance (1 study): One replicated, randomized, paired, controlled study on mudflats in the USA found that root-dipping smooth cordgrass Spartina alterniflora before planting had mixed effects on cordgrass density after 1–2 growing seasons, but never increased it. VEGETATION STRUCTURE Height (1 study): One replicated, randomized, paired, controlled study on mudflats in the USA found that root-dipping smooth cordgrass Spartina alterniflora before planting had mixed effects on cordgrass height after two growing seasons. OTHER Survival (1 study): One replicated, randomized, paired, controlled study on mudflats in the USA found that root-dipped smooth cordgrass Spartina alterniflora plants typically had a lower survival rate, after one growing season, than plants that had not been root-dipped. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3352https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3352Sun, 11 Apr 2021 17:13:05 +0100Collected Evidence: Collected Evidence: Apply root dip to trees/shrubs before planting: freshwater wetlandsWe found no studies that evaluated the effects – on trees/shrubs typical of freshwater wetlands – of applying a non-fungal root dip before planting.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3353https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3353Sun, 11 Apr 2021 17:13:16 +0100Collected Evidence: Collected Evidence: Apply root dip to trees/shrubs before planting: brackish/saline wetlandsWe found no studies that evaluated the effects – on trees/shrubs typical of brackish/saline wetlands – of applying a non-fungal root dip before planting.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3354https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3354Sun, 11 Apr 2021 17:13:29 +0100Collected Evidence: Collected Evidence: Prune roots of non-woody plants before planting: freshwater wetlandsWe found no studies that evaluated the effects – on emergent, non-woody plants typical of freshwater wetlands – of pruning their roots before planting.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3355https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3355Sun, 11 Apr 2021 17:23:33 +0100Collected Evidence: Collected Evidence: Prune roots of non-woody plants before planting: brackish/saline wetlandsWe found no studies that evaluated the effects – on emergent, non-woody plants typical of brackish/saline wetlands – of pruning their roots before planting.   ‘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%2Fwww.conservationevidence.com%2Factions%2F3356https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3356Sun, 11 Apr 2021 17:23:56 +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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