Roadside Revegetation

PLANNING PHASE THREE: VEGETATION ANALYSIS
6.1 INTRODUCTION
Phase One began by defining the overall objectives of the revegetation project, the management
areas (revegetation units), and the natural models (reference sites). It included conducting
preliminary assessments of vegetation, climate, soils, and pollinator status, and concluded with
development of the DFC for each revegetation unit. Phase Two covered how to determine which
site factors either limit or encourage the establishment of vegetation and which treatments
can be used to improve the project site for plant establishment. Phase Three describes how
to select the species and target plant requirements for each revegetation unit. Target plant
requirements include types of plant material to use (stocktypes), genetic considerations,
timing of outplanting window, and outplanting tools and techniques.
6.2 SELECT SPECIES FOR PROPAGATION
From the comprehensive species spreadsheet developed in Chapter 4 (Table 4-5), each species
is evaluated for its potential to be used on the project. This is accomplished by sorting the
spreadsheet using some or all of the following criteria:
◾◾
Nativity. If the revegetation objectives call for using native plants, then species on the
comprehensive species list are first sorted by whether it is native or not.
◾◾
Workhorse species. The next sort is by workhorse species. Workhorse species is a term
used to describe locally adapted native plants that: (1) have broad ecological amplitude,
(2) high abundance, and (3) are relatively easy to propagate. A list of workhorse species
for ecoregions (Level III) can be obtained using the EWPPS tool discussed in Section
4.3.3.2, Ecoregional Workhorse and Pollinator Plant Selector. Because these lists are still
in development, some species may need to be evaluated for potential as a workhorse
species based on the project objectives and needs.
To determine if a species, not listed as a workhorse in the Ecoregional Revegetation
Assistant tool, is a potential workhorse species, sort the comprehensive species list
by amplitude and abundance columns. Those species that have high amplitude and
abundance are good candidates for workhorse species status. From these species,
evaluate how easy they are to propagate. This includes the availability of the starter
plant materials, how easy the species is to propagate in the nursery or seed production
fields, how well the seeds store, the survival of the plant materials once they are installed
on the project, and expense.
◾◾
Availability of starter plant materials. Seeds, plants, and cuttings often have to be
collected in the wild and supplied to the nursery or seed producer for plant production,
seed increase, or stooling beds. Species that are difficult to obtain or collect are not
good candidates for workhorse species status (see Section 10.2.1, Collecting Wild Seeds,
through Section 10.2.3, Collecting Wild Plants).
◾◾
Nursery and seed production. Species that are difficult to propagate in the nursery,
stooling beds, or seed production fields do not make good workhorse species (see
Section 10.2.4, Nursery Seed Production, through Section 10.2.6, Nursery Plant Production).
Since new techniques in propagating native species is constantly improving,
talking to nursery managers or seed growers, in addition to referring to documented
plant production protocols available on the internet, is important in maintaining a
current workhorse species list.
◾◾
Longevity. Seeds that have a poor shelf life under seed standard storage practices
(seed germination that drops significantly after one year in storage) are often not good
candidates (see Section 10.2.4, Nursery Seed Production).
◾ ◾ Field establishment. The ease that a plant material will establish on a project site
will determine if a species is a workhorse species (see Section 10.3, Collecting Wild
Roadside Revegetation: An Integrated Approach to Establishing Native Plants and Pollinator Habitat 137