Every native plant community has a recognizable, and somewhat predictable, structure based on the dominant and subordinant vegetation. A forest has a towering canopy of trees that influence what can and cannot grow beneath them. A grassland has a similar structure, but the plants are herbaceous instead of woody, and this vertical structure is re-created above ground each growing season, not over decades and centuries as in a forest. Plants within a given community also create patterns of distribution on the landscape as a result of environmental factors such as soil, moisture, and light.
Different species thrive with different amounts of moisture, for example.
In a prairie, shrubs will grow in the wettest areas, grasses and forbs on the slightly higher and drier land. As a result of these factors, plant communities have recognizable vertical and horizontal structure. Ecological gardeners use the structure of the native plant community as the basis for structuring their gardens. The ground layer is where gardeners can create a tapestry of wildflowers, ferns, and grasses in beds and borders. Ecological gardeners know that structuring a garden like the native plant community also helps support birds and butterflies and other wildlife by offering them an array of spaces for feeding, breeding, resting, and nesting.