Field edge habitat in homogeneous agricultural landscapes can serve multiple purposes including enhanced biodiversity, water quality protection, and habitat for beneficial insects, such as native bees and natural enemies. Despite this ecosystem service value, adoption of field border plantings, such as hedgerows, on large-scale mono-cropped farms is minimal. With profits primarily driving agricultural production, a major challenge affecting hedgerow plantings is linked to establishment costs and the lack of clear economic benefits on the restoration investment. Our study documented that hedgerows are economically viable to growers by enhancing beneficial insects and natural pest control and pollination on farms. With pest control alone, our model shows that it would take 16 yr to break even from insecticide savings on the US$4,000 cost of a typical 300-m hedgerow field edge planting. By adding in pollination benefits by native bees, where honey bees (Apis mellifera L.) may be limiting, the return time is reduced to 7 yr. USDA cost share programs allow for a quicker return on a hedgerow investment. Our study shows that over time, small-scale restoration can be profitable, helping to overcome the barrier of cost associated with field edge habitat restoration on farms.

a b s t r a c tWithin-farm habitat enhancements such as hedgerows could aid pest control in adjacent crops; however, there is little information on whether small-scale restoration impacts pests and natural enemies, and crop damage, and how far effects may extend into fields. We compared restored, California native perennial hedgerows to unenhanced field edges consisting of commonly occurring semi-managed, nonnative weeds. Pest and natural enemy communities were assessed in both edge types and into adjacent processing tomato fields. Using sentinel pest eggs, pest control was quantified, and pest pressure and crop damage was compared between field types. Economically-important pests were fewer and parasitoid wasps were more abundant in hedgerows than weedy crop edges. There was no difference in predatory arthropod abundance between edge types, but there was greater predator richness in hedgerow than weedy edges. Predatory lady beetles were more abundant and aphids were lower in fields with hedgerows, up to 200 m into fields, the maximum extent of observations. Fewer of the fields adjacent to hedgerows reached threshold pest levels requiring insecticide application. Benefits of hedgerows to pest control from parasitism extended to 100 m but not 200 m into fields. Farm-scale hedgerow restoration can provide pest control benefits up to 100 or 200 m into fields and multiple hedgerows around fields could enhance pest control throughout entire fields, reducing the need for chemical pest control.

Marking studies demonstrated that lady beetles, lacewings, syrphid flies and parasitic wasps fed on nectar or pollen provided by borders of flowering plants around farms; many insects moved 250 feet into adjacent field crops. Studies using the elemental marker rubidium also showed that syrphid flies, parasitic wasps and lacewings fed on flowering cover crops in orchards and that some moved 6 feet high in the tree canopy and 700 feet away from the treated area. The use of nectar or pollen by beneficial insects helps them survive and reproduce. Therefore, planting flowering plants and perennial grasses around farms may lead to better biological control of pests in nearby crops.A A close up of toothpick weed (A. visnaga) covered with beneficial insects. 4 Entomologist Andrew Corbett sprays a rubidium solution onto toothpick weed (A. visnaga) at Lindell Farms in Fresno County to track the movement of beneficial insects.

Policy makers are increasingly encouraging farmers to protect or enhance habitat on their farms for wildlife conservation. However, a lack of knowledge of farmers' opinions toward wildlife can lead to poor integration of conservation measures. We surveyed farmers to assess their perceptions of ecosystem services and disservices from perching birds, raptors, and bats-three taxa commonly targeted by conservation measures. The majority of farmers thought that perching birds and bats were beneficial for insect pest control and that raptors were beneficial for vertebrate pest control; however, fruit farmers viewed perching birds more negatively than did farmers growing other crops. Farmers using organic methods viewed all three wildlife groups more positively than conventional farmers. Farmer perception toward each wildlife group predicted their action to either attract or deter those taxa, suggesting the need to focus research and outreach on the effects of wildlife on farms for conservation programs to positively influence farmer perceptions.

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