Pollinator Communities of Planted and Feral <i>Pyrus calleryana</i>

Abstract

Pyrus calleryana was intentionally introduced to North America from east Asia in the early 1900s as rootstock for the edible pear tree, Pyrus communis. It was identified as an ideal decorative, agricultural, and horticultural tree because of its small stature, early spring flowering, fire blight resistance and inoffensive fruits. P. calleryana escaped cultivation and is now considered an invasive species, typically found on roadsides, prairies, and fields. The aim of this study is to characterize pollinator community diversity from planted and feral trees, as well as diversity as it compares to expected communities derived from research-grade iNaturalist observations. Pollinators were collected by hand on planted and feral P. calleryana trees in April 2018–2022. A total of 14 taxa of insect pollinator were collected from P. calleryana flowers, with similar levels of diversity of pollinator taxa collected from planted and feral trees, and Apis mellifera and Andrena spp. the most common taxa observed. The sampled pollinator community did not differ from the expected pollinator communities generated using the iNaturalist data on either the planted or feral P. calleryana.

Keywords

• plant-pollinator interactions
• Callery pear
• Bradford pear
• plant invasion
• honeybee
• Andrenidae