Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Use alley croppingParasitism, infection and predation: Two of four studies from Kenya and the USA (including three randomised, replicated, controlled trials) found that effects of alley cropping on parasitism varied between study sites, sampling dates, pest life stages or the width of crop alleys. Two studies found no effect on parasitism. One study found mixed effects on fungal infections in pests and one study found lower egg predation. Natural enemies: One randomised, replicated, controlled study from Kenya found more wasps and spiders but fewer ladybirds. Some natural enemy groups were affected by the types of trees used in hedges. Pests and crop damage: Two of four replicated, controlled studies (two also randomised) from Kenya, the Philippines and the UK found more pests in alley cropped plots. One study found fewer pests and one study found effects varied with pest group and between years. One study found more pest damage to crops but another study found no effect. Weeds: One randomised, replicated, controlled study from the Philippines found mixed effects on weeds, with more grasses in alley cropped than conventional fields under some soil conditions. Yield: One controlled study from the USA found lower yield and one study from the Philippines reported similar or lower yields. Costs and profit: One study from the USA found lower costs but also lower profit in alley cropped plots. Crops studied were alfalfa, barley, cowpea, maize, pea, rice and wheat.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F718https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F718Thu, 30 May 2013 10:53:35 +0100Collected Evidence: Collected Evidence: Plant new hedgesNatural enemies: One randomised, replicated, controlled study from China compared plots with and without hedges and found no effect on spiders in crops. One of two studies from France and China found more natural enemies in a hedge than in adjacent crops while one study found this effect varied between crop types, hedge species and years. Two randomised, replicated, controlled studies from France and Kenya found natural enemy abundance in hedges was affected by the type of hedge shrub/tree planted and one also found this effect varied between natural enemy groups. Pests: One randomised, replicated, controlled study from Kenya compared fallow plots with and without hedges and found effects varied between nematode (roundworm) groups. Crops studied were barley, beans, maize and wheat.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F752https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F752Thu, 01 Aug 2013 09:28:37 +0100Collected Evidence: Collected Evidence: Use mass-emergence devices to increase natural enemy populationsParasitism: One randomised, replicated, controlled study in Switzerland found higher parasitism at one site but no effect at another site when mass-emergence devices were used in urban areas. Pest damage: The same study found no effect on pest damage to horse chestnut treesCollected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F775https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F775Tue, 20 Aug 2013 16:35:29 +0100