Collected Evidence: Collected Evidence: Use prescribed fire: effects on mature trees Four of eight studies (including two replicated, randomized, controlled studies) from the USA found that prescribed fire decreased tree cover, density and diversity. One study found it increased tree cover and three found no effect or mixed effects of prescribed fire on cover and density of trees. Seven studies from the USA (including one replicated, randomized, controlled study) found that prescribed fire increased tree mortality. One of three studies from the USA (including one replicated, controlled study) found that prescribed fire increased tree size while two found no effect of prescribed fire on tree size.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1217https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1217Fri, 20 May 2016 14:09:36 +0100Collected Evidence: Collected Evidence: Use herbicides to remove understory vegetation to reduce wildfires We found no evidence for the effects of using herbicides to remove understory vegetation to reduce wildfiress. '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%2F1218https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1218Fri, 20 May 2016 14:40:39 +0100Collected Evidence: Collected Evidence: Mechanically remove understory vegetation to reduce wildfires We found no evidence for the effects of mechanically removing understory vegetation to reduce wildfires. '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%2F1219https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1219Fri, 20 May 2016 14:42:38 +0100Collected Evidence: Collected Evidence: Use prescribed fire: effects on young trees Five of 15 studies (including four replicated, randomized, controlled studies) from Canada, France and the USA found that prescribed fire increased the density and biomass of young trees. Two studies found that fire decreased new tree density. Eight found no effect or mixed effects depending on the tree species, location and fire frequency. Two of the above studies found mixed effects of prescribed fire on species diversity of young trees depending on the location. Two replicated, controlled studies from the USA found mixed effects of prescribed fire on the survival of young trees.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1220https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1220Fri, 20 May 2016 14:45:40 +0100Collected Evidence: Collected Evidence: Use prescribed fire: effect on understory plants Eight of 22 studies (including seven replicated, randomized, controlled studies) from the USA, Australia and Canada found that prescribed fire increased the cover, density and biomass of understory plants. Six of the studies found it decreased plant cover. Eight found no effect or mixed effects on cover and density of understory plants. Fourteen of 24 studies (including ten replicated, randomized, controlled studies) from the USA, Australia, France and West Africa found that prescribed fire increased species richness and diversity of understory plants. One study found that it decreased species richness.  Nine found no effect or mixed effects on species richness and diversity of understory plants.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1221https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1221Mon, 23 May 2016 08:21:42 +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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