Roadside Revegetation

PLANNING PHASE ONE: ORIENT
Once revegetation objectives are developed, they direct the development and implementation
of the revegetation plan and the monitoring plan.
The next step is to understand the environment of the project site: its climate, soils, natural
vegetation, and potential as pollinator habitat. Much of this information is available in
reports and on websites. Collecting and reviewing this information gives the planner a more
comprehensive understanding of the project prior to conducting a site visit. The site visits
check the accuracy of the background information, and this information is refined to the
project scale. Soils, vegetation, and climate are surveyed, and areas with similar environments
and common objectives are grouped into management areas, called revegetation units.
Revegetation units are distinct areas within the project that have different management
strategies. A project consisting of sites with little variation in topography, soils, vegetation
types, and microclimate may comprise a single revegetation unit. Most project sites, however,
contain different soils, climate, and vegetation types, and therefore require the delineation
of several distinct revegetation units.
Once revegetation units have been delineated, reference sites are located in or near the project
site. Reference sites serve as models for revegetation planning, and later for monitoring and
evaluating project success (SER 2004). Reference sites can be undisturbed areas as well as areas
that have been disturbed but have recovered. In either case, reference sites demonstrate a
desirable trajectory of recovery. For roadside revegetation purposes, some of the best reference
sites have undergone some disturbance but have revegetated over time with functioning
communities of native plants. Reference sites illustrate desirable developmental pathways
and plant communities that should be attainable for the revegetation units.
At this point, background information is sufficient to effectively survey the road project. Plant
surveys of reference sites are used to develop a comprehensive species list that will be used to
develop species lists for each revegetation area. Confirming the soils and climate information
obtained during pre-field data collection will be used to develop the appropriate soil and
site improvement treatments, as well as the type of plant materials to provide. Assessing
the quality of the pollinator habitat and diversity and quantity of pollinator species will lead
to development of appropriate improvement measures. By the end of the field survey, the
designer should have a good understanding of the effects that the road project will have on
soils, vegetation, climate, and pollinator habitat and with this information develop the DFCs
for each revegetation unit. DFCs specify guidelines (percentage of vegetative cover, plant
species, etc.) appropriate for each revegetation unit in the project area. The DFCs will later
become the basis for developing a monitoring plan.
4.2 DEFINE REVEGETATION OBJECTIVES
The design objectives of a road project guide the development of the revegetation plan. As
discussed in Chapter 2, road objectives usually involve goals of improving safety and efficiency,
as well as environmental health. Revegetation objectives develop from road objectives and
become the foundation of the revegetation and monitoring plans. It is important to develop
a clear set of revegetation objectives early in the planning phase. When these objectives are
understood and expectations are clear, the development and implementation of a revegetation
plan are easier and more successful. Most roadside revegetation projects share the common
objective of initiating and/or accelerating the process of natural succession near the roadside
in order to establish self-sustaining native plant communities (Brown and Amacher 1999;
Clewell and others 2005). This objective usually reflects larger project goals, stated in terms
of increasing pollinator habitat, protecting soil and water resources, enhancing roadside
aesthetics, limiting invasive plants, and improving road safety and function while protecting
environmental health. Later in the planning process, revegetation objectives are used to
develop specific goals (stated as DFCs) for evaluating the success of the revegetation work.
Table 4-2 defines some terms commonly used in defining revegetation objectives. Clarifying
Roadside Revegetation: An Integrated Approach to Establishing Native Plants and Pollinator Habitat
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