2019 ASHS Annual Conference

Many species of pollinators, especially honeybees and wild bees, are experiencing decline due to forage and habitat losses. Planting flowering perennial species is one of the recommendations to reduce bee decline. The goal of our study was to evaluate four commonly available genera of perennials for their ability to attract pollinators and beneficial arthropods in an urban landscape (Fargo) and a rural landscape (Absaraka) in North Dakota. The four genera were bee balm (Monarda L. spp.), stonecrop (Hylotelephium H. Ohba spp.), false indigo (Baptisia Vent. spp.), and aster (Symphyotrichum Nees spp.). A mix of six to eight species and/or cultivars were planted per genus in 2018 with six replications per location. Each plant was observed weekly during flowering for three minutes and the number of visits from pollinators and beneficial arthropods were counted. Examples of pollinators included honeybees, bumblebees, black bees, metallic bees, butterflies, moths, and syrphid flies. Beneficial arthropods were parasitic wasps, yellow jackets, ants, minute pirate bugs, lady beetles, green lacewings, spiders, and daddy long-legs. A total of 756 arthropod specimens were observed at the Fargo site, and 2,731 specimens at Absaraka. In Fargo, 93.1% of specimens were pollinators and 6.4% were beneficial arthropods. Observations at Absaraka indicated 74.4% of the specimens were pollinators and 25.6% were beneficial arthropods. The genera Hylotelephium and Symphyotrichum attracted more pollinator visits at both locations. In Absaraka, Symphyotrichum and Hylotelephium spp. attracted the majority of beneficial arthropod visits. Very few beneficial arthropods were observed at the Fargo site. No data were available from Baptisia plants because they flowered prior to transplanting. The landscape effect is one of the potential reasons for higher arthropod specimen numbers at the Absaraka site compared to Fargo. Absaraka is located in a rural, wooded area. In contrast, the Fargo plots are located in an urban area with regular mosquito spraying during the summer months. Overall, Hylotelephium, Symphyotrichum, and Monarda spp. show promise to attract pollinators and beneficial arthropods.