Collected Evidence: Collected Evidence: Enhance soil compaction Three studies (including two replicated, randomized, controlled) in Canada and the USA found that soil compaction decreased tree regeneration height and density. Two of the studies found it increased understory plant cover and density, while one found it decreased understory plant species richness.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1253https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1253Fri, 03 Jun 2016 14:05:56 +0100Collected Evidence: Collected Evidence: Fence to prevent grazing after tree planting Four of five studies (including two replicated, randomized, controlled studies) in Australia, Canada , Finland and the USA found that using fences to exclude grazing increased the survival, size and cover of planted trees. Two studies found no effect on tree survival rate and one found mixed effects on planted tree size depending on the structure of the fence.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1254https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1254Fri, 03 Jun 2016 14:24:30 +0100Collected Evidence: Collected Evidence: Use prescribed fire after tree planting Two of four studies (including one replicated, randomized, controlled study) in Finland, France and the USA found that using prescribed fire after replanting increased the survival and sprouting rate of planted trees.  One study found fire decreased planted tree size and one found no effect of prescribed fire on the size and survival rate of planted trees.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1255https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1255Fri, 03 Jun 2016 15:33:52 +0100Collected Evidence: Collected Evidence: Mechanically remove understory vegetation after tree planting Five studies (including three replicated, randomized, controlled studies) in Canada, the USA, France, Panama and Sweden found no effect of controlling understory vegetation on the emergence, survival, growth rate or frost damage in planted seedlings. However, one found removing competing herbs increased seedling biomass. One replicated, controlled study in Canada found that removal of sheep laurel shrubs increased the growth rate and height of planted black spruce seedlings.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1256https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1256Mon, 06 Jun 2016 09:06:01 +0100Collected Evidence: Collected Evidence: Manage woody debris before tree planting One replicated, randomized, controlled study in Canada found that removal of woody debris increased the survival rate of planted trees. One replicated, controlled study in the USA found mixed effects of removing, chopping and burning woody debris on the size of planted trees.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1257https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1257Mon, 06 Jun 2016 09:39:53 +0100Collected Evidence: Collected Evidence: Add organic matter after tree planting Two replicated, randomized, controlled studies in the USA found that adding leaf litter or wood-chips before restoration planting increased seedling biomass, but decreased seedling emergence and survival.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1258https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1258Mon, 06 Jun 2016 10:36:39 +0100Collected Evidence: Collected Evidence: Add lime to the soil after tree planting One of two replicated, randomized, controlled studies in the USA found that adding lime before restoration planting decreased the survival of pine seedlings. The other study found no effect of adding lime on planted oak seedling growth.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1259https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1259Mon, 06 Jun 2016 10:42:49 +0100Collected Evidence: Collected Evidence: Use fertilizer after tree planting Two replicated, controlled studies in Canada and Portugal found that applying fertilizer after planting increased the size of the planted trees. One randomized, replicated, controlled study in Australia found that soil enhancers including fertilizer had a mixed effect on seedling survival and height. Three studies (including two randomized, replicated, controlled study) in France and Australia found no effect of applying fertilizer on the size and survival rate or health of planted trees.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1260https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1260Mon, 06 Jun 2016 10:48:59 +0100Collected Evidence: Collected Evidence: Use mechanical thinning before or after planting Five of six studies (including two replicated, randomized, controlled studies) in Brazil, Canada, Finland, France and the USA found that thinning trees after planting increased survival and size of the planted trees. One study found it decreased their density. One study found that the effects of thinning on the size and survival rate of planted trees varied between species. One replicated study in the USA found that the survival rate of red oak seedlings increased with the size of the thinned area.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1261https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1261Mon, 06 Jun 2016 11:04:37 +0100Collected Evidence: Collected Evidence: Use herbicides after tree planting Two of three studies (including two replicated, randomized, controlled studies) in Sweden and the USA found that using herbicide increased the size of planted trees. One study found no effect on tree size. One replicated, randomized, controlled study in Sweden found no effect of using herbicide on frost damage caused to planted Norway spruce seedlings.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1262https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1262Mon, 06 Jun 2016 13:13:27 +0100Collected Evidence: Collected Evidence: Prepare the ground before tree planting Six of seven studies (including five replicated, randomized, controlled studies) in Canada and Sweden found that ground preparation treatments increased the survival and growth rate of planted trees. One study found no effect of creating mounds on frost damage of planted Norway spruce seedlings.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1263https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1263Mon, 06 Jun 2016 14:23:39 +0100Collected Evidence: Collected Evidence: Use different planting or seeding methods Four studies (including one replicated, randomized study) in Australia, Brazil, Costa Rica and Mexico found no effect of planting or seeding methods on the size and survival rate of seedlings. One replicated, controlled study in Brazil found that planting early succession pioneer tree species decreased the height of other planted species.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1264https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1264Mon, 06 Jun 2016 15:01:28 +0100Collected Evidence: Collected Evidence: Cover the ground with straw after tree planting One replicated, randomized, controlled study in the Czech Republic found that covering the ground with straw, but not bark or fleece, increased the growth rate of planted trees and shrubs.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1266https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1266Fri, 10 Jun 2016 08:44:29 +0100Collected Evidence: Collected Evidence: Use weed mats to protect planted trees One replicated, controlled study in Hong Kong found no effect of using weed mats on thick-leaved oak seedling height.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1267https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1267Fri, 10 Jun 2016 08:53:49 +0100Collected Evidence: Collected Evidence: Use tree guards or shelters to protect planted trees One replicated, randomized, controlled study in the USA found that using light but not dark coloured plastic tree shelters increased the survival rate of planted tree seedlings. One replicated, controlled study in Hong Kong found that tree guards increased tree height after 37 but not 44 months.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1268https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1268Fri, 10 Jun 2016 09:07:23 +0100Collected Evidence: Collected Evidence: Use shading for planted trees One replicated, controlled study in Panama found that shading increased the survival rate of planted native tree seedlings.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1269https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1269Fri, 10 Jun 2016 09:19:59 +0100Collected Evidence: Collected Evidence: Log/remove trees within forests: effects on non-vascular plants Two of three studies (including one replicated, paired sites study) in Australia, Norway and Sweden found logging trees in forests decreased epiphytic plant abundance and fern fertility. One found mixed effects depending on species.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1270https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1270Fri, 10 Jun 2016 09:37:49 +0100Collected Evidence: Collected Evidence: Log/remove trees within forests: effects on mature trees Three of seven studies (including two replicated, controlled studies) in Bolivia, Central African Republic, China, Finland, Malaysia, Uganda and the USA found that logging trees in forests decreased the density and cover of trees. Two found it increased tree density and two found no effect of logging on tree density. Three of six studies (including one replicated, randomized, controlled study) in Bolivia, Canada, China, Kenya, Malaysia and the USA found that logging trees in forests increased tree size. Two found it decreased tree size and one found no effect of  logging on tree size. Two of four studies (including one paired site study) in Bolivia, China, Mexico and Papua New Guinea found that logging trees in forests decreased tree species richness and diversity. One study found it increased diversity and one found no effect of logging on tree species diversity. One replicated, controlled study in Canada found that logging trees in forests increased tree mortality rate.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1271https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1271Mon, 13 Jun 2016 08:55:36 +0100Collected Evidence: Collected Evidence: Log/remove trees within forests: effects on young trees One replicated controlled study in Canada found that logging trees in forests increased the density of young trees. One replicated controlled study in Costa Rica found mixed effects on the density of young trees.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1272https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1272Mon, 13 Jun 2016 09:18:50 +0100Collected Evidence: Collected Evidence: Log/remove trees within forests: effects on understory plants Five of ten studies (including four replicated, randomized, controlled studies) in Bolivia, Canada, India and the USA found that logging trees in forests increased the density and cover of understory plants. Five studies found no effect or mixed effects. Four of seven studies (including one replicated, randomized, controlled study) in Australia, Canada and the USA found that logging trees in forests increased species richness and diversity of understory plants. Three studies found no effect.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1273https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1273Mon, 13 Jun 2016 09:29:47 +0100Collected Evidence: Collected Evidence: Use vegetation removal together with mechanical disturbance to the soil Two studies (including one replicated, randomized, controlled study) in Portugal and France found that vegetation removal together with mechanical disturbance of the soil increased the cover and diversity of understory plants. One of the studies found it also decreased understory shrub cover. One replicated, randomized, controlled study in France found that vegetation removal together with mechanical disturbance of the soil increased the density of young trees.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1274https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1274Tue, 28 Jun 2016 10:55:55 +0100Collected Evidence: Collected Evidence: Use herbicides to remove invasive plant species One replicated, randomized, controlled study in the USA found no effect of invasive plant control using herbicide on the total native plant species richness.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1314https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1314Fri, 23 Sep 2016 14:49:03 +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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