23 U.S.C. § 319 — Landscaping and scenic enhancement

This section funds highway landscaping, requires wildflower planting, and promotes pollinator habitat. (a) Landscaping and roadside development. The Secretary can approve, as part of building Federal-aid highways, the cost of landscaping and roadside development. This includes buying and developing publicly owned rest and recreation areas and sanitary facilities reasonably needed for travelers, and buying interests in, and improving, strips of land next to highways to restore, preserve, or enhance scenic beauty — including improving habitat and forage for pollinators. (b) Planting native wildflowers. (1) The Secretary must require native wildflower seeds or seedlings to be planted as part of any landscaping project. At least one-quarter of one percent of the money spent on that landscaping project must go toward these plantings. (2) The Secretary can waive this requirement if a state certifies that native wildflowers can't grow well there, or that the planting areas are limited or already used for farming. (3) This subsection doesn't stop a landscaping project from accepting donated native wildflower seeds or seedlings from civic groups, other organizations, or individuals. (c) Encouraging pollinator habitat. In running any program under this title, the Secretary must work with willing states to: (1) encourage integrated vegetation management on roadsides and other transportation rights-of-way, including mowing less; and (2) encourage planting native forbs and grasses — including noninvasive native milkweed — to build habitat and forage for Monarch butterflies, other native pollinators, and honey bees. Milkweed in particular can serve as a stopover point for migrating butterflies and help other pollinators migrate too.