The major addition to the county's program for better roadsides has been the establishment of roadside planting jobs. Areas are seeded where the county crews have cleaned a ditch, or have done construction projects and left bare soil.
These projects are seeded into prairie vegetation. A quick establishing cover crop or a blend of cover crops is used to provide immediate erosion control. The area is also seeded with a permanent crop of native grasses and flowers that are specifically suited to the soil and conditions of each site.
As the quick growing cover crops establish, they stabilize the soil and fight immediate erosion. The slower establishing native grasses and flowers usually show up the second and third seasons, (although in some situations they come in year one). These are native species, that means they were here in Iowa before all of the common, "farm grasses" such as brome, orchardgrass and timothy were introduced from Europe.
This also means that the native plants are adapted to Iowa's soil and to Iowa's weather patterns. This makes them very valuable to us in the roadsides because they will grow under any conditions that the climate can throw at them.
Native plants are slower to establish, but they are perennial plants which come back yearly from root. The root systems are 7-10 feet deep on many of these plants. In the roadside setting, this is crucial. Not only do they prevent erosion better, they compete with weeds for below surface root space.
The more root mass a plant has, the better they can compete. As they establish, they thicken and with proper management they thrive.
Why Native Plants Matter
Iowa Living Roadway Trust Fund
Iowa Natural Heritage Fund
Iowa Prairie Network
Tallgrass Prairie Center