Creating Pollinator Habitat Along Roadsides

Winslow Way, Bainbridge Island, WA / image: Alexandra Hay

Below, you’ll find a re-post from Entomology Today of “Study Finds Bees Can Have Their Wildflowers and Almonds, Too” by Josh Lancette—a timely subject, with Pollinator Week later this month and an ASLA Online Learning webinar on the topic, Creating Pollinator Habitat Along Roadsides, coming up on June 14 hosted by the Transportation PPN.

The post discusses the use of wildflower planting strips adjacent to almond orchards in California. While at first blush it might appear that this practice has little to do with transportation, keep in mind that millions of miles of rural roadways are adjacent or proximate to agricultural fields. Furthermore, Section 130 of the Surface Transportation and Uniform Relocation Assistance Act of 1987 (STURAA) added a requirement that native wildflower seeds or seedlings or both be planted as part of any landscaping project undertaken on the federal-aid highway system. This requirement is mandatory and applies only to federal funded landscaping projects. One quarter to one percent of funds used for landscaping projects must be used to plant native wildflowers.

Other federal initiatives promoting the use of native wildflower plantings exist. USDA’s Natural Resources Conservation Service (NRCS) defines a field border as a “strip of permanent vegetation established at the edge or around the perimeter of an agricultural field.” The practice is used, among other things, to provide pollinator habitat and to manage agricultural pest populations. Field borders assist with agricultural pest management by providing habitat to beneficial organisms or as a place for agricultural pests to congregate. When field borders are designed for pollinator habitat, they have been shown to facilitate pollination services to agricultural crops. A properly designed field border provides nectar and pollen sources for pollinators when the target crops are not in bloom. This practice is currently being used in Michigan, where “flowering plant strips” increase crop productivity through the support of beneficial insects and pollinators.

Landscape architects engaged in planting roadside vegetation must be thoughtful. Selecting plant material so the crops are not harmed (e.g. plum pox virus, which attacks stone crops) but are benefited should be an integral part of the planting program.

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