Roadside Revegetation

PLANNING PHASE ONE: ORIENT
4.6.1 VEGETATION ASSESSMENT
The objective of assessing the vegetation of a reference site is to create a comprehensive
species list that will guide in the selection of species to be used for revegetating the project
area. A good method for compiling a comprehensive species list is to choose a representative
cross section of each reference site that will characterize the range of plant species for that
unit. Intuitively controlled surveys, such as these, maximize floristic knowledge yet are less
time and effort intensive than complete floristic inventories. Usually, a few plant species are
not easily identified in the field. Samples of these species can be brought back to the office
for identification by specialists. If more detailed data collection is desired, such as a complete
floristic inventory, surveys along transects or grids may be conducted.
Once species are identified, a comprehensive species list is developed for the project (Table 4-5).
This list will be used throughout the life of the project for selecting species for plant propagation,
weed control, and plant protection. It includes some or all of the following attributes:
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Species name (common and scientific). Since common names for plant species
change throughout the country, it is important to list both the scientific and common
names of each species. The PLANTS database (http://plants.usda.gov) is a good source
for obtaining the current scientific and common names. The PLANTS database also
includes the short species code symbol for field documentation.
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Revegetation unit. Identify the revegetation units where the species occurred.
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Ecological settings. Plants are identified by the ecological setting they are most
commonly found in. A relative rating by temperature (cold, cool, warm, hot) and
moisture (dry, moist, wet) gives a quick profile of the ecological setting. Some portions
of the U.S. are covered by plant association maps or reports that were developed by
federal agencies and are good sources for identifying the ecological setting of a species.
Another way to describe the ecological setting of a species is by using the Ecological
Site Assessment section of the Web Soil website (see Section 4.3.2 Soils). This part of the
website groups soil mapping units into ecological site units and dominant plant species.
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Amplitude. Ecological amplitude is the recurrence of a species across a wide array
of ecological settings. A species found in all ecological settings would have a high
ecological amplitude, while a species found in only one ecological setting would have
a low ecological amplitude.
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Abundance. The quantity, dominance, or cover of a species found in a revegetation
unit is the abundance.
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Life form. Group each species by life form: (1) tree, (2) shrub, (3) annual grass, (4) perennial
grass, (5) annual forb, (6) perennial forb, or (7) wetland species (e.g., sedges, rushes)
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Nativity. Identify whether the species is native to the local area or introduced. The
PLANTS database identifies the nativity of all plant species in the U.S.
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Weed status. The PLANTS database identifies the noxious weeds for each state. State-listed
noxious weeds are found under the heading “Introduced, Invasive, and Noxious
Plants” under the “PLANTS Topics” sidebar. Contacting the local State agency incharge
of maintaining the lists, usually state departmnents of Ag is highly recommended.
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Threatened and endangered. State and federal protected plants are found in the
PLANTS database under the heading “Threatened & Endangered” on the “PLANTS
Topics” sidebar.
◾ ◾ Succession. Determine the seral stage a species is most commonly associated with: (1)
early, (2) mid, (3) late, or (4) climax. Visiting reference sites and adjacent areas at different
ages of recovery following disturbance will help provide an understanding of where each
species fits into ecological succession. Figure 4-10 illustrates how plant communities
develop differently over time depending on site conditions and successional processes.
Roadside Revegetation: An Integrated Approach to Establishing Native Plants and Pollinator Habitat
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