Interstate highway systems and networks of dense urban roads typically receive top billing on maps, in infrastructure legislation and in travelers' daily commuting routes. However, more than 80% of all US roads are considered low-volume roads—defined as those that carry fewer than 1000 vehicles per day. According to a new report published by the Ecological Society of America, "The Ecology of Rural Roads: Effects, Management and Research," this less-traveled road network can have an outsized impact on surrounding ecosystems, altering the local hydrology, affecting wildlife populations and shuttling invasive species into new areas.