Assessing Pollinator Habitat Value of Managed Plant Communities using Pollinator Site Value Indices (PSVI) and Implications for Infrastructure Investment
Authors: Michael R. Haggie, Richard A. Johnstone & Hubert A. Allen
EXECUTIVE SUMMARY
A Presidential memorandum created a federal strategy on pollinators in 2014 due to the decline of honey bees, native bees, birds, bats, and butterflies. Sixty million acres of existing energy and transportation service rights-of-way (ROW) criss-cross private, public and tribal nations lands, an acreage on par with the national park system. As America upgrades its infrastructure, pollinator and bird habitat can simultaneously be restored on a massive scale simply by upgrading ROW vegetation maintenance practices from mowing to integrated vegetation management (IVM).
Traditional mechanical mowing maintenance hinders climate resiliency efforts and environmental enhancements by increasing greenhouse gas emissions and spreading nonnative invasive plants. IVM can reduce a carbon footprint by managing for native prairie meadow habitat, requiring less maintenance and lower costs. Documentation of habitat improvement has already been established through research by IVM Partners, a nonprofit organization, on energy and highway ROW.
No index existed to measure the relative benefits of the studied plant communities to pollinators until a nectar and pollen quality ranking for Mid-Atlantic plants was published in the 2014 book, “Garden Plants for Honey Bees.” This ranking provided a legitimate means to develop a pollinator site value index (PSVI), which measures the quality of habitat from the perspective of the pollinators, beginning with Apis (honey bee) and expanding to Bombus (bumblebee).
A complementary ranking compiled by University of Delaware researchers lists Mid-Atlantic plants that serve as food for Lepidoptera (moth and butterfly) larvae, a ranking which has since been expanded to plants across the entire United States. A PSVI measure of these larval host food plants ranks the vegetative community benefit for lepidopterans, as well as for song and game birds, since these same insects are a vital food source for birds. By applying these two PSVI indices with ROW plant community documentation over time, one can accurately assess the success of integrated vegetation management (IVM) methods to not only meet the primary objectives of energy and transportation services to the public, but also to restore prime habitat for pollinators and birds.
Plant identification training by community colleges can develop skilled workers and regional botany technicians necessary to apply and assess IVM best practices on ROW. IVM Partners, as a non-profit organization and current liaison for federal, state, and tribal governments, utilities, universities, and com-munity colleges, is uniquely positioned to help develop the curriculum and coordinate implementation. As we rebuild our nation’s infrastructure, we must invest in the education and training necessary to restore habitat for insects and birds that pollinate our crops and feed a hungry world.