Naturalized habitat on golf courses: source or sink for natural enemies and conservation biological control?

Abstract

Many golf courses are converting out-of-play areas to meadow-like habitat to reduce mowing, irrigation, and chemical inputs. Such naturalized roughs, which often constitute 50 % or more of a course's total acreage, support biodiversity by providing habitat for pollinators and other wildlife. This study explored the hypothesis that they also serve as reservoirs of invertebrate natural enemies whose services extend to suppress pests in adjacent mowed turf. We used vacuum sampling, pitfall traps, and ant baits to compare arthropod populations in grassland or meadow-type naturalized roughs and traditional mowed roughs at two courses, and tested for spillover of biological control using sentinel eggs or larvae of a grass-feeding caterpillar exposed near or farther from naturalized areas into mowed turf. Although some natural enemies (e.g., spiders) were more abundant in naturalized roughs, we saw no direct spillover of predation which was quite high regardless of habitat type. Most likely that is because ground-nesting ants (Lasius, Solenopsis, and Pheidole spp.), which are dominant predators in this system, were equally or more abundant in the mowed turfgrass. Herbivorous insects, too, were more abundant in naturalized roughs, so prey availability may discourage solitary ground-dwelling predators from leaving those refuges to forage in mowed areas. There was no parasitism of sentinel eggs or larvae in our trials. Despite absence of direct spillover of predation, we argue that naturalized roughs might be more purposely designed and managed to promote parasitoids, insectivorous birds, and other enemies that provide diffuse biological control services elsewhere on the course.Land-use planners and landscape managers are being challenged to design relatively more sustainable landscapes that provide for the aesthetic, restorative, and recreational needs of Urban Ecosyst

Mixed-Species Gardens Increase Monarch Oviposition without Increasing Top-Down Predation

“…The North American monarch population provides an excellent model system to optimize conservation strategies that may be applicable to other specialist herbivores and butterflies [ 1 , 2 , 5 ]. Agricultural and urban land use types are leveraging the multifunctionality of conservation plantings by converting areas to flowering habitats to conserve pollinators while promoting top-down regulation of economic pests [ 9 , 23 , 24 , 69 , 70 ]. Recent work and this study suggest that monarch conservation plantings may also serve this multifunctionality.…”

Evaluation of ‘Jackal’ AR601 (Avanex) and Kentucky‐31 Endophytic Tall Fescues for Suppressing Types of Invertebrates that Contribute to Bird Strike Hazard at Airports

“…Marketing claims that Avanex will reduce invertebrate populations enough to discourage visitation by insectivorous birds are based on pilot trials conducted in New Zealand from which inferences were drawn from small sample sizes, rough metrics such as “total invertebrate dry weight” without regard to taxon (Pennell et al, 2010, 2015), and comparisons between Jackal AR601 and existing airport vegetation, the latter an uncultivated mix of grasses, legumes, and weeds that based on habitat complexity alone would be expected to support greater abundance and diversity of macroinvertebrates than does a mowed grass monoculture (Albrecht et al, 2010; Hudewenz et al, 2012; Dobbs and Potter, 2016). We acknowledge that our study, conducted in one non–airport location, is not necessarily indicative of how Avanex would affect invertebrate communities across different regions, soil types, and environmental conditions.…”

“…Vacuum sampling for leafhoppers and other surface‐dwelling turf insects was done with a gasoline‐powered leaf blower (Troy‐Bilt, Cleveland, OH) reversed for suction with a paint strainer bag clamped inside the intake tube to trap arthropods and plant litter (Dobbs and Potter, 2016). Samples were collected on 27 May, 25 July, and 22 Sept. 2014, all clear sunny days, coinciding with the pitfall sampling.…”

Assessment of management of a golf course by means of sustainability indicators

“…) that affect management of a golf course and in this way it is consistent with findings of Dai et al (2016), who pointed out that ecological benefits produced by golf course are higher than dis-services, in terms of financial accounting. These ecological services can also be enhanced by particular management reserved to rough areas that can play an important role in conservation of particular environments with typical plants and to improve pollination activity (Dobbs and Potter, 2016).…”