Research Idea Details

Research Idea Scope

Roadsides in the United States cover an area equal to 100,000 football fields for every state (TRB 1997) and are often refuges for rare native plants. These areas represent an enormous societal resource warranting creative thinking and careful research. Roadsides today are designed primarily for the safety of vehicles that run off the road, with little attention to other values important to society, such as harboring of rare plants.

Currently, much is known about the types of roadside plants and vegetation and the relative abundance of native and exotic (nonnative) plants present in these areas (Harper-Lore 1999). On the other hand, only a partial picture emerges for rare plants at roadsides, the ecological effects of mowing, and the effects of vehicle- and road-generated chemicals.

Many important roadside-related questions remain unanswered. For example, which spatial and temporal controls are ecologically best for native plants, butterflies, birds, and whole communities (Natuur Over Wegen 1995, Forman and Alexander 1998)? What wildlife species should and should not be encouraged by increasing food and/or cover in roadside areas? How can bridges, signs, and other road structures be designed to increase the populations of desirable species? What are the main sources for colonization of roadside exotic species, and how often do exotics spread along roadsides (Harper-Lore 1999)? Which chemical substances from vehicles and roads affect roadside vegetation and animals (FHWA 1996)? How much absorption and breakdown of chemicals occurs at roadsides, and would this increase if there were more woody vegetation and wetland? Finally, how can roadsides be designed to educate neighbors and travelers ecologically?

TERI Administrator Note (June 2007): Related Research
NCHRP Synthesis Report: Interaction Between Roadways and Wildlife Ecology (2002)