Collected Evidence: Collected Evidence: Sow grass seeds Thirteen studies examined the effects of sowing grass seeds on grassland vegetation. Six studies were in North America, five studies were in Europe and one study was in each of Canada and South Africa. VEGETATION COMMUNITY (6 STUDIES) Community composition (2 studies): One of two paired studies (one of which was replicated, randomized and controlled) in Hungary and the UK found that, over time, plant communities in areas where grass seeds were sown and in areas where no seeds were sown became more similar to those of intact grasslands. The other study found that plant communities in sown areas were different from those of ancient grasslands or sites where natural regeneration was allowed. Overall richness/diversity (4 studies): Three of four studies (three of which were replicated and controlled, and one of which was a site comparison) in the UK, Hungary, Iceland and the USA found that sowing grass seeds did not change or reduced overall plant species richness. The other study found that species richness was lower than that found in nearby intact prairies. Native/non-target species richness/diversity (1 study): One replicated, controlled study in the USA found that sowing grass seeds did not alter the species richness of native plants. VEGETATION ABUNDANCE (10 STUDIES) Overall abundance (3 studies): Two of three studies (including two replicated, controlled studies and one site comparison) in the USA, Iceland and Norway found that sowing grass seeds increased vegetation cover. The other study found that in two of three years there was no difference in vegetation cover between areas where grass seeds were sown and those where no seeds were sown. Characteristic plant abundance (1 study): One replicated, randomized, paired, controlled study in Hungary found that sowing grass seeds reduced the abundance of grassland species. Sown/planted species abundance (1 study): One replicated, controlled study in South Africa found that sowing grass seeds increased the abundance of sown species. Grass abundance (4 studies): Three of four replicated studies (two of which were randomized, controlled studies and the other a site comparison) in the USA and Canada found that sowing grass seeds either reduced native grass cover or did not alter native grass density. The other study found that after two years grass cover was higher in areas where grass seeds were sown than in areas were no seeds were sown, but after seven years there was no longer a difference between areas. Forb abundance (2 studies): One of two replicated studies (one randomized, controlled study and one site comparison) in the USA and Canada found that sowing grass seeds reduced the abundance of native forb species. The other study found no change in the density of native forb species. Tree/shrub abundance (2 studies): Two replicated studies (one randomized, controlled study and one site comparison) in the USA and Canada found that sowing grass seeds reduced the abundance of shrub species. Native/non-target species abundance (1 study): One replicated, controlled study in the USA found that sowing grass seeds did not alter the cover of native plant species. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3397https%3A%2F%2Fconservationevidence.com%2Factions%2F3397Fri, 25 Jun 2021 13:05:51 +0100Collected Evidence: Collected Evidence: Sow grassland forb species One study examined the effects of sowing grassland forb species on grassland vegetation. The study was in Belgium. VEGETATION COMMUNITY (0 STUDIES) VEGETATION ABUNDANCE (0 STUDIES) VEGETATION STRUCTURE (0 STUDIES) OTHER (1 STUDY) Germination/Emergence (1 study): One replicated, controlled study in Belgium found that sowing seeds of grassland forb species did not increase the number of seedlings for three forb species. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3398https%3A%2F%2Fconservationevidence.com%2Factions%2F3398Fri, 25 Jun 2021 13:53:08 +0100Collected Evidence: Collected Evidence: Plant grassland plants Four studies examined the effects of planting grassland plants on grassland vegetation. One study was in each of the UK, Germany and the USA. One review included studies from the UK and Australia. VEGETATION COMMUNITY (2 STUDIES) Overall richness/diversity (1 study): One replicated, controlled study in the USA found that planting seedlings in addition to sowing seeds increased the number of plant species compared to sowing seeds alone. Grass richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that planting plants increased species richness of grasses in 50% of cases. Forb richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that planting plants increased species richness of forbs in 83% of cases. Native/non-target richness/diversity (1 study): One replicated, controlled study in the USA found that planting plants in addition to sowing seeds increased the number of native plant species compared to sowing seeds alone. VEGETATION ABUNDANCE (2 STUDIES) Individual plant species abundance (1 study): One study in Germany found that transplanted pepper saxifrage plants increased in number and spread to adjacent grassland. Sown/planted species abundance (1 study): One review in the UK and Australia found that planting grassland plants had mixed effects on planted species abundance. VEGETATION STRUCTURE (0 STUDIES) OTHER (1 STUDY) Survival (1 study): One study in Germany found that 44% of new seedlings from transplanted pepper saxifrage plants survived over four months. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3399https%3A%2F%2Fconservationevidence.com%2Factions%2F3399Fri, 25 Jun 2021 13:56:45 +0100Collected Evidence: Collected Evidence: Sow grassland seeds from a local source Five studies examined the effects of sowing grassland seeds from a local source on grassland vegetation. Two studies were in Germany, two were in the USA and one was in Italy. VEGETATION COMMUNITY (2 STUDIES) Overall richness/diversity (1 study): One replicated, controlled study in Italy found that sowing grassland seeds from a local source increased plant species richness compared to sowing a commercial seed mix. Characteristic plant richness/diversity (1 study): One replicated, controlled study in Germany found that sowing grassland seeds from a local source, along with increasing the number of species in a seed mix, led to an increase in the species richness of target plants. VEGETATION ABUNDANCE (3 STUDIES) Overall abundance (2 studies): One of two replicated studies (including one site comparison and one controlled study) in the USA and Germany found that after sowing grassland seeds from a local source vegetation cover increased over time compared to areas sown with non-native seeds, but the density of individual plants declined. The other study found that vegetation cover did not differ to that in areas sown with commercial grass seed. Characteristic plant abundance (2 studies): One replicated, controlled study in Germany found that sowing grassland seeds from a local source, along with increasing the number of species in a seed mix, led to an increase in the cover of target plant species. One replicated, randomized, paired, controlled study in Germany found that sowing grassland seeds from a local source increased the abundance of one of four characteristic plant species that were sown. VEGETATION STRUCTURE (2 STUDIES) Height (2 studies): Two replicated studies (including one controlled and one site comparison study) in the USA and Italy found that sowing grassland seeds from a local source did not alter vegetation height compared to sowing non-native grass seeds or a commercial seed mix. OTHER (1 STUDY) Survival (1 study): One replicated, randomized, controlled experiment in the USA found that sowing Sandberg bluegrass seeds from a local source did not change the survival of sown plants compared to sowing non-local varieties. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3400https%3A%2F%2Fconservationevidence.com%2Factions%2F3400Fri, 25 Jun 2021 14:08:23 +0100Collected Evidence: Collected Evidence: Sow or plant nurse plants (alongside seeding/planting of grassland species) Four studies examined the effects of sowing or planting nurse plants alongside seeding/planting grassland species on grassland vegetation. Two studies were in Europe, one study was in the USA and one was in Kenya. VEGETATION COMMUNITY (1 STUDY) Community composition (1 study): One replicated, controlled study in Slovenia found that sowing a seed mix containing nurse species resulted in a community composition that was less similar to the target community when compared to sowing a seed mix that did not contain nurse species. Overall richness/diversity (1 study): One replicated, controlled study in Slovenia found that sowing a seed mix containing nurse species did not increase species richness compared to sowing a seed mix that did not contain nurse species. VEGETATION ABUNDANCE (1 STUDY) Grass abundance (1 study): One replicated, paired, controlled study in the USA found that sowing seeds of nurse plants alongside that of grassland species did not change grass abundance. Forb abundance (1 study): One replicated, paired, controlled study in the USA found that sowing seeds of nurse plants alongside that of grassland species did not change forb abundance. VEGETATION STRUCTURE (0 STUDIES) OTHER (2 STUDIES) Germination/Emergence (1 study): One replicated, controlled study in Spain found that sowing seeds under nurse plants increased seed germination. Survival (2 studies): One of two replicated, controlled studies (one of which was randomized and paired) in Kenya and Spain found that sowing seeds or planting under nurse plants increased survival of planted plants. The other study found that sowing seeds under nurse plants initially increased seedling survival, but there was no difference in survival after two to three years. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3402https%3A%2F%2Fconservationevidence.com%2Factions%2F3402Fri, 25 Jun 2021 14:22:50 +0100Collected Evidence: Collected Evidence: Increase number of species in seed mix Five studies examined the effects of increasing the number of species in a seed mix on grassland vegetation. Four studies were in the USA and one was in Germany. VEGETATION COMMUNITY (4 STUDIES) Overall richness/diversity (1 study): One replicated, site comparison study in the USA found that increasing the number of species in a seed mix did not change plant species richness. Characteristic plant richness/diversity (1 study): One replicated, controlled study in Germany found that increasing the number of species in a seed mix, along with sowing seeds from a local source, increased the species richness of target plants. Sown/planted species richness/diversity (2 studies): Two replicated, controlled studies in the USA (one of which was randomized) found that increasing the number species in a seed mix increased the species richness of sown plants. VEGETATION ABUNDANCE (3 STUDIES) Characteristic plant abundance (1 study): One replicated, controlled study in Germany found that increasing the number of species in a seed mix, along with sowing seeds from a local source, increased the cover of target plant species. Sown/planted species abundance (2 studies): One of two replicated, controlled studies (one of which was randomized) in the USA found that increasing the number of species in a seed mix increased the cover of sown plant species. The other study found that there was no change in the cover of sown species. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3406https%3A%2F%2Fconservationevidence.com%2Factions%2F3406Fri, 25 Jun 2021 14:56:06 +0100Collected Evidence: Collected Evidence: Drill seed rather than seeding by hand Five studies examined the effects of drill seeding rather than sowing by hand on grassland vegetation. The studies were in the USA. VEGETATION COMMUNITY (3 STUDIES) Overall richness/diversity (3 studies): Two of three replicated, controlled studies (two of which were paired) in the USA found that sowing seeds with a seed drill did not alter plant species richness. The other study found mixed effects. VEGETATION ABUNDANCE (4 STUDIES) Sown/planted species abundance (3 studies): One of three replicated, controlled studies (two of which were randomized and one paired) in the USA found that sowing seeds with a seed drill increased the density of two sown grass species compared to sowing by hand. The two other studies found that in most cases sowing seeds with a seed drill led to no change or a reduction in the abundance of sown plants compared to hydroseeding or sowing by hand. Grass abundance (1 study): One replicated, paired, controlled study in the USA found that sowing grassland seeds with a seed drill increased the abundance of warm-season grass species compared to sowing by hand. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3410https%3A%2F%2Fconservationevidence.com%2Factions%2F3410Fri, 25 Jun 2021 15:23:50 +0100Collected Evidence: Collected Evidence: Disturb soil before seeding/planting Seven studies examined the effects of disturbing soil before seeding/planting on grassland vegetation. Five studies were in Europe and one study was in each of the USA and China. VEGETATION COMMUNITY (3 STUDIES) Overall richness/diversity (2 studies): One of two replicated, controlled studies in the UK and Germany found that disturbing soil before sowing seeds increased plant and seedling species richness. The other study found no change in plant species richness or diversity. Grass richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that rotovating soil before sowing seeds increased grass species richness in most cases compared to harrowing before sowing. Forb richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that rotovating soil before sowing seeds increased forb species richness in most cases compared to harrowing before sowing. VEGETATION ABUNDANCE (2 STUDIES) Overall abundance (1 study): One replicated, controlled study in the UK found that disturbing soil before sowing seeds did not alter total plant biomass. Forb abundance (1 study): One replicated, randomized, paired, controlled study in the USA found that disturbing soil before sowing forb seeds increased the cover of forb species. VEGETATION STRUCTURE (0 STUDIES) OTHER (5 STUDIES) Germination/Emergence (5 studies): Four of five replicated, controlled studies (three of which were randomized and paired) in the USA, Germany, China and Spain found that disturbing soil before sowing seeds increased plant emergence in most cases compared to sowing alone. The other study found no change in seed germination. Survival (2 studies): One of two replicated, controlled studies (one of which was randomized and paired) in China and Spain found that disturbing soil before sowing seeds increased the survival of seedlings. The other study found that ploughing to disturb soil followed by planting did not alter the survival of planted species. Growth (1 study): One replicated, randomized, paired, controlled study in the USA found that disturbing soil before planting forb seedlings had no effect on seedling growth. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3413https%3A%2F%2Fconservationevidence.com%2Factions%2F3413Fri, 25 Jun 2021 15:51:17 +0100Collected Evidence: Collected Evidence: Remove leaf litter before seeding/planting Three studies examined the effects of removing leaf litter before seeding/planting on grassland vegetation. One study was in each of Germany, Belgium and Hungary. VEGETATION COMMUNITY (0 STUDIES) VEGETATION ABUNDANCE (2 STUDIES) Sown/planted species abundance (1 study): One replicated, randomized, paired, controlled study in Hungary found that removing leaf litter before sowing seeds did not increase the cover of either of two sown grass species. Individual plant species abundance (1 study): One replicated, controlled study in Germany found that removing leaf litter before planting did not alter the biomass of ragged robin and marsh birdsfoot trefoil transplants in most cases. VEGETATION STRUCTURE (0 STUDIES) OTHER (3 STUDIES) Germination/Emergence (3 studies): Two of three replicated, controlled studies (one of which was also randomized and paired) in Germany, Belgium and Hungary found that removing leaf litter, and in one study also removing vegetation, before sowing seeds had mixed effects on the number of seedlings of sown plant species. The other study found no change in the number of seedlings of either of two grass species. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3414https%3A%2F%2Fconservationevidence.com%2Factions%2F3414Fri, 25 Jun 2021 16:00:36 +0100Collected Evidence: Collected Evidence: Remove topsoil or turf before seeding/planting Six studies examined the effects of removing topsoil or turf before seeding/planting on grassland vegetation. Three studies were in the UK, two studies were in the USA and one was in France. VEGETATION COMMUNITY (3 STUDIES) Community composition (1 study): One replicated, randomized, controlled study in France found that removing topsoil before sowing seeds increased plant community similarity to that of intact steppe. Overall richness/diversity (1 study): One replicated, randomized, controlled study in France found that removing topsoil before sowing seeds increased plant species richness. Sown/planted species richness/diversity (1 study): One replicated, controlled study in the UK found that removing topsoil before sowing seeds increased the species richness of sown plants. Grass richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that removing turf before sowing seeds increased grass species richness in most cases compared to disturbing the soil before sowing. Forb richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that removing turf before sowing seeds increased forb species richness in most cases compared to disturbing the soil before sowing. VEGETATION ABUNDANCE (2 STUDIES) Overall abundance (1 study): One replicated, randomized, controlled study in France found that removing topsoil before sowing seeds did not alter overall vegetation cover. Sown/planted species abundance (1 study): One replicated, randomized, controlled study in the UK found that removing topsoil before planting seedlings led to higher cover of planted species. Individual species abundance (1 study): One replicated, randomized, controlled study in the UK found that removing topsoil before planting seedlings led to lower cover of common knapweed. VEGETATION STRUCTURE (0 STUDIES) OTHER (2 STUDIES) Survival (2 studies): Two replicated, controlled studies (one paired and one randomized) in the USA found that removing topsoil before planting California oatgrass or sowing and planting purple needlegrass increased the survival of seedlings and plants. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3415https%3A%2F%2Fconservationevidence.com%2Factions%2F3415Fri, 25 Jun 2021 16:09:07 +0100Collected Evidence: Collected Evidence: Remove vegetation before seeding/planting Two studies examined the effects of removing vegetation before seeding/planting on grassland vegetation. One study was in each of the UK and Belgium. VEGETATION COMMUNITY (0 STUDIES) VEGETATION ABUNDANCE (0 STUDIES) VEGETATION STRUCTURE (0 STUDIES) OTHER (2 STUDIES) Germination/Emergence (2 studies): One of two replicated, controlled studies in the UK and Belgium found that removing vegetation before sowing seeds increased the germination rate of sown species. The other study found that removing vegetation, along with removing leaf litter, before sowing seeds increased the number of seedlings for one of three species. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3416https%3A%2F%2Fconservationevidence.com%2Factions%2F3416Fri, 25 Jun 2021 16:14:10 +0100Collected Evidence: Collected Evidence: Burn vegetation before seeding/planting We found no studies that evaluated the effects of burning vegetation before seeding/planting on grassland vegetation. ‘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%2Fconservationevidence.com%2Factions%2F3417https%3A%2F%2Fconservationevidence.com%2Factions%2F3417Fri, 25 Jun 2021 16:16:14 +0100Collected Evidence: Collected Evidence: Apply herbicide before seeding/planting Four studies examined the effects of applying herbicide before seeding/planting on grassland vegetation. Two studies were in the USA and one study was in each of Germany and the UK. VEGETATION COMMUNITY (1 STUDY) Sown/planted species richness/diversity (1 study): One replicated, controlled study in the UK found that applying herbicide before sowing seeds increased sown species richness. VEGETATION ABUNDANCE (2 STUDIES) Sown/planted species abundance (1 study): One replicated, randomized, controlled study in the USA found that spraying with herbicide before sowing seeds increased the cover of sown grass species. Forb abundance (1 study): One replicated, randomized, controlled study in the USA found that spraying with herbicide before sowing grass seeds did not alter or reduced the density of native forb species. Tree/shrub abundance (1 study): One replicated, randomized, controlled study in the USA found that spraying with herbicide before sowing grass seeds led to an increase in the density of shrubs. Individual plant species abundance (1 study): One replicated, randomized, controlled study in the USA found that spraying with herbicide before sowing grass seeds did not alter the density of crested wheatgrass. VEGETATION STRUCTURE (0 STUDIES) OTHER (1 STUDY) Germination/Emergence (1 study): One replicated, randomized, paired, controlled study in Germany found that spraying with herbicide before sowing seeds increased seedling emergence for five of eight wildflower species. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3418https%3A%2F%2Fconservationevidence.com%2Factions%2F3418Fri, 25 Jun 2021 16:22:52 +0100Collected Evidence: Collected Evidence: Mow before or after seeding/planting Ten studies examined the effects of mowing before or after seeding/planting on grassland vegetation. Nine studies were in Europe and one was in China. VEGETATION COMMUNITY (5 STUDIES) Community composition (1 study): One replicated, site comparison study in Hungary found that annual mowing after sowing seeds increased plant community similarity to that of natural grassland. Overall richness/diversity (1 study): One replicated, controlled study in the UK found that cutting vegetation yearly after sowing seeds increased plant species richness compared to grazing with livestock. Characteristic plant richness/diversity (1 study): One replicated, controlled study in Germany found that cutting vegetation three times/year after sowing seeds increased the richness of characteristic grassland species compared to cutting once/year. Sown/planted species richness/diversity (2 studies): One replicated, randomized, paired, controlled study in the UK found that mowing after sowing seeds increased the richness of sown species. One replicated study in the UK found that cutting sown plots each year and removing cut vegetation increased sown grass and forb species richness compared to cutting and not removing cut vegetation. VEGETATION ABUNDANCE (4 STUDIES) Sown/planted species abundance (3 studies): One replicated, randomized, paired, controlled study in the UK found that mowing after sowing seeds increased the abundance of sown forb species. One replicated, randomized, paired, controlled study in Germany found that mowing more frequently after sowing seeds increased the abundance of five of seven sown forb species. One replicated study in the UK found that cutting sown plots each year and removing cut vegetation reduced the cover of sown grass and forb species compared to cutting and not removing cut vegetation. Individual plant species abundance (1 study): One replicated, controlled study in Germany found that mowing after planting increased the biomass of transplanted ragged robin and birdsfoot trefoil plants at 2–3 of seven sites. VEGETATION STRUCTURE (0 STUDIES) OTHER (4 STUDIES) Germination/Emergence (3 studies): One of three replicated, controlled studies (including two randomized and one paired study) in the UK, Germany and China found that mowing after sowing seeds increased the germination of four grassland plant species. One study found that mowing after sowing seeds increased the number of ragged robin and birdsfoot trefoil seedlings at 1–2 of seven sites. One study found that cutting grass after sowing seeds did not alter the emergence rate or density of seedlings. Survival (2 studies): One of two replicated, randomized, paired, controlled studies in Germany and China found that cutting grass after sowing seeds did not alter seedling survival. The other study found that cutting grass after sowing seeds did not alter seedling survival. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3419https%3A%2F%2Fconservationevidence.com%2Factions%2F3419Fri, 25 Jun 2021 16:29:54 +0100Collected Evidence: Collected Evidence: Add topsoil before seeding/planting One study examined the effects of adding topsoil before seeding/planting on grassland vegetation. The study was in the USA. VEGETATION COMMUNITY (1 STUDY) Overall richness/diversity (1 study): One replicated, controlled study in the USA found that adding topsoil before sowing seeds increased plant species richness. VEGETATION ABUNDANCE (1 STUDY) Sown/planted species abundance (1 study): One replicated, controlled study in the USA found that adding topsoil before sowing seeds increased the biomass of sown species in most cases. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3420https%3A%2F%2Fconservationevidence.com%2Factions%2F3420Fri, 25 Jun 2021 16:37:29 +0100Collected Evidence: Collected Evidence: Add woody debris to protect seeds/plants One study examined the effects of adding woody debris to protect seeds/plants on grassland vegetation. The study was in Kenya. VEGETATION COMMUNITY (0 STUDIES) VEGETATION ABUNDANCE (0 STUDIES) VEGETATION STRUCTURE (0 STUDIES) OTHER (1 STUDY) Survival (1 study): One replicated, randomized, controlled study in Kenya found that sowing buffel grass seeds beside woody debris did not affect seedling survival. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3421https%3A%2F%2Fconservationevidence.com%2Factions%2F3421Fri, 25 Jun 2021 16:40:28 +0100Collected Evidence: Collected Evidence: Add charcoal to soil before seeding/planting One study examined the effects of adding charcoal to soil before seeding/planting on grassland vegetation. The study was in the Netherlands. VEGETATION COMMUNITY (0 STUDIES) VEGETATION ABUNDANCE (1 STUDY) Overall abundance (1 study): One replicated, randomized, paired, controlled study in the Netherlands found that adding charcoal to soil before sowing seeds did not alter overall plant biomass. Grass abundance (1 study): One replicated, randomized, paired, controlled study in the Netherlands found that adding charcoal to soil before sowing seeds did not alter grass cover. Forb abundance (1 study): One replicated, randomized, paired, controlled study in the Netherlands found that adding charcoal to soil before sowing seeds increased the cover of legumes but did not alter the cover of other forbs. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3422https%3A%2F%2Fconservationevidence.com%2Factions%2F3422Fri, 25 Jun 2021 16:43:15 +0100Collected Evidence: Collected Evidence: Graze with livestock after seeding/planting Seven studies examined the effects of grazing with livestock after seeding/planting on grassland vegetation. Five studies were in Europe, one study was in New Zealand and one was in the USA. VEGETATION COMMUNITY (5 STUDIES) Overall richness/diversity (2 studies): One replicated, randomized, paired, controlled study in Italy found that grazing with livestock after sowing seeds increased plant species richness compared to sowing without grazing. One replicated, controlled study in the UK found that grazing with livestock after sowing seeds reduced plant species richness compared to cutting vegetation after sowing. Sown/planted species richness/diversity (2 studies): One replicated study in the UK found that grazing with cattle after sowing seeds increased sown species richness compared to grazing with sheep. One replicated, randomized, controlled study in New Zealand found that grazing with sheep continuously after sowing seeds did not alter sown species richness compared to grazing on rotation. Native/non-target species richness/diversity (1 study): One replicated, controlled study in the USA found that grazing with cattle after sowing seeds increased native plant species richness compared to sowing without grazing. VEGETATION ABUNDANCE (4 STUDIES) Characteristic plant abundance (1 study): One replicated, controlled study in Hungary found that grazing with livestock after sowing seeds did not alter the cover of target plant species compared to sowing without grazing. Sown/planted species abundance (2 studies): One replicated study in the UK found that grazing with cattle after sowing seeds reduced the cover of sown species compared to grazing with sheep. One replicated, randomized, controlled study in New Zealand found that grazing with sheep continuously after sowing seeds increased the cover of four of eight sown species compared to grazing on rotation. Native/non-target species abundance (1 study): One replicated, controlled study in the USA found that grazing with cattle after sowing seeds reduced the cover of native plant species compared to sowing without grazing. VEGETATION STRUCTURE (0 STUDIES) OTHER (1 STUDY) Survival (1 study): One replicated, randomized, controlled study in the UK found that grazing in the winter after sowing seeds resulted in higher survival of cut-leaved cranesbill seedlings. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3423https%3A%2F%2Fconservationevidence.com%2Factions%2F3423Mon, 28 Jun 2021 09:32:18 +0100Collected Evidence: Collected Evidence: Add mulch before or after seeding/planting Six studies examined the effects of adding mulch before or after seeding/planting on grassland vegetation. Two studies were in Canada, two were in the USA, and one study was in each of the UK and Germany. VEGETATION COMMUNITY (1 STUDY) Characteristic plant richness/diversity (1 study): One replicated, controlled study in Germany found that adding mulch before sowing seeds did not alter the species richness of target plants. VEGETATION ABUNDANCE (4 STUDIES) Overall abundance (1 study): One replicated, controlled study in Canada found that adding mulch before sowing seeds did not increase plant cover. Characteristic plant abundance (1 study): One replicated, controlled study in Germany found that adding mulch before sowing seeds increased the cover of target plant species. Sown/planted species abundance (2 studies): One of two replicated, randomized, controlled studies in the USA and UK found that adding mulch before sowing seeds did not alter the density of six sown plant species in most cases. The other study found that adding mulch before planting seedlings reduced the cover of planted species. Individual species abundance (1 study): One replicated, randomized, controlled study in the UK found that adding mulch before planting seedlings did not alter the cover of common knapweed. VEGETATION STRUCTURE (0 STUDIES) OTHER (2 STUDIES) Germination/Emergence (1 study): One replicated, controlled study in Canada found that adding mulch before sowing seeds increased the number of seedlings in most cases. Growth (1 study): One replicated, randomized, controlled study in the USA found that adding mulch after planting native prairie plants did not alter the growth of any of seven plant species. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3425https%3A%2F%2Fconservationevidence.com%2Factions%2F3425Mon, 28 Jun 2021 10:05:54 +0100Collected Evidence: Collected Evidence: Add fertilizer to soil before or after seeding/planting Seventeen studies examined the effects of adding fertilizer to soil before or after seeding/planting on grassland vegetation. Nine studies were in North America, six studies were in Europe, one study was in China, and one was in Brazil. VEGETATION COMMUNITY (3 STUDIES) Overall richness/diversity (3 studies): One replicated, randomized, paired, controlled study in Spain found that adding fertilizer alongside sowing of non-native plant seeds increased plant diversity in 40% of cases. Two replicated, controlled studies in Spain and Italy found that plant species richness and diversity were not altered by organic matter or fertilizer addition alongside seeding. VEGETATION ABUNDANCE (13 STUDIES) Overall abundance (8 studies): Six of nine replicated, controlled studies (five of which were also randomized and paired) in North America and Europe found that adding fertilizer alongside sowing or planting increased vegetation cover in all or some cases. Three studies found no change in vegetation cover or plant density. Characteristic plant abundance (1 study): One replicated, randomized, paired, controlled study in the UK found that adding fertilizer and sowing seeds increased the abundance of specialist grassland species. Sown/planted species abundance (3 studies): Two replicated, randomized, controlled studies in the USA found that adding fertilizer after sowing seeds did not alter the density of sown forbs. One replicated, randomized, paired, controlled study in the USA found that adding fertilizer after sowing seeds increased the cover but not the density of four sown plant species. Grass abundance (1 study): One replicated, controlled study in the USA found that adding fertilizer and sowing seeds increased the biomass of three native grass species. VEGETATION STRUCTURE (0 STUDIES) OTHER (4 STUDIES) Germination/Emergence (1 study): One replicated, randomized, paired, controlled study in China found that adding fertilizer and sowing seeds did not increase seedling emergence or density. Survival (3 studies): Three replicated, controlled, paired studies (one of which was randomized) in the UK, China and Brazil found that adding fertilizer alongside sowing seeds did not alter the survival of seedlings. Growth (1 study): One replicated, randomized, controlled study in the USA found that adding fertilizer after planting native prairie plants reduced the diameter of prairie lupine plants and did not alter the growth of six other plant species. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3427https%3A%2F%2Fconservationevidence.com%2Factions%2F3427Mon, 28 Jun 2021 10:37:44 +0100Collected Evidence: Collected Evidence: Add sulphur to soil before seeding/planting Two studies examined the effects of adding sulphur to soil before seeding/planting on grassland vegetation. One study was in the UK and one was in the USA. VEGETATION COMMUNITY (2 STUDIES) Overall richness/diversity (1 study): One of two replicated, controlled studies (one of which was randomized and paired) in the UK and USA found that adding sulphur to soil before sowing seeds reduced plant species richness. The other study found no change in overall plant species richness. Native/non-target species richness/diversity (1 study): One replicated, controlled study in the USA found that adding sulphur to soil before sowing seeds did not alter the number of native plant species. VEGETATION ABUNDANCE (2 STUDIES) Overall abundance (1 study): One replicated, randomized, paired, controlled study in the UK found that adding sulphur to soil before sowing seeds reduced overall vegetation cover. Sown/planted species abundance (1 study): One replicated, randomized, paired, controlled study in the UK found that adding low amounts of sulphur to soil before sowing seeds increased the cover of three of six sown species. Native/non-target species abundance (1 study): One replicated, controlled study in the USA found that adding sulphur to soil before sowing seeds did not alter the cover of native plant species. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3428https%3A%2F%2Fconservationevidence.com%2Factions%2F3428Mon, 28 Jun 2021 10:48:32 +0100Collected Evidence: Collected Evidence: Inoculate soil with mycorrhiza before seeding/planting Five studies examined the effects of inoculating soil with mycorrhiza before seeding/planting on grassland vegetation. Four studies were in the USA and one was in Germany. VEGETATION COMMUNITY (1 STUDY) Overall richness/diversity (1 study): One replicated, randomized, controlled study in Germany found that inoculating soil with mycorrhizal fungi and sowing seeds of grassland species did not alter plant species richness. VEGETATION ABUNDANCE (4 STUDIES) Overall abundance (2 studies): One replicated, randomized, paired, controlled study in the USA found that inoculating soil with mycorrhizal fungi before sowing seeds initially increased vegetation cover, but after three years, vegetation cover did not differ between areas that were and were not inoculated. One controlled study in the USA found that adding soil microbes and nutrients when planting grass plugs did not change the overall cover of herbaceous species. Characteristic plant abundance (2 studies): One replicated, randomized, controlled study in Germany found that adding mycorrhiza to the soil and sowing seeds of grassland species increased the abundance of target species that were considered a local conservation priority. One controlled study in the USA found that adding soil microbes and nutrients when planting grass plugs increased the cover of three of 38 native prairie species. Tree/shrub abundance (1 study): One controlled study in the USA found that adding soil microbes and nutrients when planting grass plugs did not change the cover of woody species. Native/non-target species abundance (1 study): One replicated, controlled study in the USA found that adding mycorrhizal fungi to soil before sowing seeds did not alter the biomass of three native grass and forb species. VEGETATION STRUCTURE (1 STUDY) Height (1 study): One replicated, controlled study in the USA found that adding mycorrhizal fungi to soil before sowing seeds increased the height of giant sacaton plants. Individual plant size (1 study): One replicated, controlled study in the USA found that adding mycorrhizal fungi to soil before sowing seeds did not increase the biomass of giant sacaton plants. OTHER (1 STUDY) Germination/Emergence (1 study): One replicated, controlled study in the USA found that adding mycorrhizal fungi to soil before sowing seeds did not increase the emergence of giant sacaton plants. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3429https%3A%2F%2Fconservationevidence.com%2Factions%2F3429Mon, 28 Jun 2021 13:23:20 +0100Collected Evidence: Collected Evidence: Irrigate before or after seeding/planting Two studies examined the effects of irrigating before or after seeding/planting on grasslands. One study was in Spain and one in the USA. VEGETATION COMMUNITY (2 STUDIES) Overall richness/diversity (2 studies): One of two replicated, controlled studies (one of which was randomized and paired) in Spain and the USA found that irrigating after sowing non-native seeds increased plant diversity in four of 10 cases. The other study found that irrigating after sowing native seeds did not alter plant species richness. Native/non-target species richness/diversity (1 study): One replicated, controlled study in the USA found that irrigating after sowing seeds did not alter the species richness of native plants. VEGETATION ABUNDANCE (2 STUDIES) Overall abundance (1 study): One replicated, randomized, paired, controlled study in Spain found that irrigating after sowing non-native seeds increased vegetation cover in six of 10 cases. Native/non-target species abundance (1 study): One replicated, controlled study in the USA found that irrigating after sowing seeds did not alter the cover of native plant species. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3430https%3A%2F%2Fconservationevidence.com%2Factions%2F3430Mon, 28 Jun 2021 13:31:34 +0100Collected Evidence: Collected Evidence: Sow native grass and forbs Fifty studies examined the effects of sowing native grass and forb seeds on grassland vegetation. Thirty-six studies were in Europe, twelve studies were in North America and one study was in New Zealand. One review included studies from Europe, North America and Africa. VEGETATION COMMUNITY (42 STUDIES) Community composition (11 studies): Five of 11 studies (10 of which were replicated and/or controlled, and three of which were site comparisons) in the UK, the Czech Republic, Norway and Germany found that sowing native grass and forb seeds increased the similarity of plant community composition to that of target communities. Three studies found no increase in community similarity to target communities. Two studies found that over time communities became more similar to those of intact grasslands. One study found that over time areas sown with native grass and forb seeds became more similar to areas that were not sown with seeds. Overall richness/diversity (28 studies): Sixteen of 28 studies (24 of which were controlled and four of which were site comparisons) in Europe, North America and New Zealand found that sowing native grass and forb seeds increased overall plant species richness. Seven studies found that there was no change in plant species richness or mixed effects on plant species richness and plant diversity. Three studies found that sowing native grass and forb seeds increased plant species richness during the first year, but after 3–13 years, species richness did not differ between sown and unsown areas or was lower in sown areas. One study found that after one year, sowing did not alter plant species richness but after eight years, species richness was higher than in unsown areas. Three studies found that species richness was lower in sown areas than in nearby intact grasslands. Characteristic plant richness/diversity (9 studies): Six of nine studies (eight of which were replicated and/or controlled, and two of which were site comparisons) in Europe found that sowing native grass and forb seeds increased the species richness of characteristic grassland plants. Two studies found no change in the species richness of characteristic grassland plants. One study found that sowing native grass and forb seeds increased the species richness of target forbs but not target grasses. Sown/planted species richness/diversity (3 studies): Three replicated, paired, controlled studies in the UK and the Czech Republic found that sowing native grass and forb seeds increased sown species richness. Grass richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that sowing native grass and forb seeds increased grass species richness in 54% of cases. Forb richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that sowing native grass and forb seeds increased forb species richness in 71% of cases. Native/non-target richness/diversity (1 study): One replicated, controlled study in the USA found that sowing native grass and forb seeds increased the species richness of native plants. VEGETATION ABUNDANCE (24 STUDIES) Overall abundance (8 studies): Three of eight replicated, controlled studies (four of which were randomized and paired) in Europe and North America found that sowing native grass and forb seeds increased overall vegetation cover, biomass or density. One study found that sowing native grass and forb seeds increased plant species richness during the first 2–7 years, but after eight years, species richness did not differ between sown and unsown areas. Four studies found that there was no change in overall vegetation abundance in all or most cases. Characteristic plant abundance (5 studies): Three of five replicated studies (four of which were controlled, and one of which was a site comparison) in Europe found that sowing native grass and forb seeds did not alter the cover of characteristic grassland species. The other two studies found an increase in the cover of characteristic or target grassland species. Sown/planted species abundance (6 studies): Five of six studies (four of which were replicated and controlled, and two of which were reviews) in Europe, North America, Africa and New Zealand found that sowing native grass and forb seeds increased the abundance of sown species in all or most cases. The other study found mixed effects on sown species abundance. Grass abundance (3 studies): Two of three replicated, randomized, controlled studies (two of which were paired) in the Czech Republic and the USA found that sowing native grass and forb seeds increased the cover of grass species. The other study found no change in the cover of grass species. Forb abundance (4 studies): Three of four replicated, randomized, controlled studies (three of which were paired) in the Czech Republic and the USA found that sowing native grass and forb seeds increased the cover or density of forb species. The other study found that one year after sowing, the cover of forb species increased, but after 10 years it did not differ between sown and unsown areas. Native/non-target species abundance (1 study): One replicated, controlled study in the USA found that sowing native grass and forb seeds increased the cover of native plant species. Individual plant species abundance (1 study): One replicated, randomized, paired, controlled study in the UK found that sowing native grass and forb seeds did not alter yellow rattle abundance. VEGETATION STRUCTURE (0 STUDIES) OTHER (2 STUDIES) Germination/Emergence (2 studies): One of two replicated, controlled studies (one of which was paired) in the USA and Germany found that sowing native grass and forb seeds increased the number of seedlings that emerged. The other study found no change in seedling number. Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3432https%3A%2F%2Fconservationevidence.com%2Factions%2F3432Mon, 28 Jun 2021 13:42:06 +0100Collected Evidence: Collected Evidence: Add carbon to soil before or after seeding/planting Two studies examined the effects of adding carbon to soil before or after seeding/planting on grassland vegetation. Both studies were in the USA. VEGETATION COMMUNITY (0 STUDIES) VEGETATION ABUNDANCE (2 STUDIES) Sown/planted species abundance (2 studies): Two replicated, randomized, controlled studies in the USA found that adding carbon to soil after sowing seeds either reduced or did not alter the density of sown forb species. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidence.com%2Factions%2F3433https%3A%2F%2Fconservationevidence.com%2Factions%2F3433Thu, 08 Jul 2021 17:12:59 +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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