State Plant Listings
How To Use Plant Lists
Native Plant lists:
The following native plant lists are intended as a beginning reference, and not as a shopping list for your next project. Every State has various natural regions due to climate and geological variation over time. The vegetation of these regions has evolved uniquely to each region. What grows in the southwest part of your State might be impossible to grow in the northeast, and so on. What grows at one elevation will be different from another. What grows on the north slope will look different from the south slope. And what grows on dry sand will be different from wet sand. Using a plant hardiness zone map will not help you make native plant species decisions. Using a natural vegetation map will help you match plant species to the environment to which they are adapted. The Natural Heritage Program, Native Plant Society, and /or The Nature Conservancy in your State can be of further help. Some universities specialize in native plants.
The native trees, shrubs, grasses, forbs, and vines on your State's list are common to your State, but not every region within the State. Not all are commercially available, but should be considered for propagation. Please use resources to further fine tune your list, in terms of desirable roadside characteristics: locally common, early successional, low-growing, seasonal, deep or fibrous-rooted, perennial, drought-resistant, noninvasive, available, affordable and aesthetically pleasing. In other words, to be successful you need to know as much about each species' life history and your objectives as possible. This knowledge will help you match the most appropriate plants to each project.
Endangered Species lists:
There is some precedent to not only protecting but planting endangered plant species to highway rights-of-way. This planting should be done only after careful study. Some States have set up a process and permit system for such reintroductions. This reintroduction is a complex issue, ecologically and politically. Be sure to contact your natural resource department or natural heritage program for guidance. On most sites, these listed species will require extra protection and a specific maintenance plan. Keep your vegetation inventory current and know where these plants exist. Only Federally listed species noted.
Noxious Weeds lists:
Not all States have noxious weed lists. Those that do typically have defined the lists by including those plants that interfere with agriculture (Canada thistle), or cause human health problems (poison ivy). Some States have added a third reason for inclusion, and that is environmental impact (Purple Loosestrife). Check this list to be sure that you are not inadvertently planting an invasive species that you are legally responsible to control. Western States are also checking with adjacent States to avoid planting their problem plants. Because weeds do not know political boundaries, and because by their very nature weeds continue to adapt and expand, watching State borders in terms of planting and vegetation management is wise.
Questions and feedback should be directed to Deirdre Remley (firstname.lastname@example.org, 202-366-0524).