Roadside Revegetation

REVEGETATION PLAN EXAMPLE
NON-NATIVE PLANT CONTROL
Non-Native Plant Control
Weed Control Plan
All Oregon Noxious Class ‘A’ and ‘B’ weeds will be treated within the construction limits
(Appendix Three). The one exception to this is herb Robert (Geranium robertianum) which
will not be targeted for treatment, as determined during site visits with WFLHD, ODOT,
CH2M, CRGNSA, and RST. Of the targeted Class A and B species the following Class B
species have been noted within Segments A-C: Canada thistle (Cirsium arvense), English
ivy, Himalayan blackberry, Scotch broom, perennial peavine (Lathyrus latifolius), and St.
Johnswort (Hypericum perforatum). Although not listed by the State, periwinkle (Vinca
minor) will also be targeted for control, as will other species that appear to impede
restoration efforts. Table 8 provides an estimated schedule of non-native plant treatment.
Only approved herbicides and surfactants will be used and all aquatic setbacks adhered to.
Personnel from partnering agencies including the Mt. Hood National Forest, Columbia
River Gorge National Scenic Area, Oregon Parks and Recreation Department, and Oregon
Department of Transportation will be consulted regarding permissible herbicides and
surfactants.
Himalayan blackberry
Himalayan blackberry will be sprayed with glyphosate or triclopyr + surfactant from a
backpack sprayer or an ATV. In the area of Mitigation Site #2 the plants will then mowed
no sooner than 3 weeks after the first spray treatment, allowed to re-sprout, and
chemically treated again. The area with the greatest concentration of Himalayan
blackberry is Mitigation Site #2, but the plants do occur throughout the segments. RST will
chemically treat these populations where they occur, but most likely will not utilize
mowing.
Scotch Broom
Scotch broom populations are most robust at the Wyeth Trailhead/parking lot and at
Mitigation Site #2. There are plants scattered throughout other areas of segments A-C, as
well as along Wyeth Road near the proposed Wyeth Trailhead and parking lot. Treatments
should include these plants that are in close proximity along Wyeth Road to prevent
immediate recolonization of Wyeth parking lot. Plants less than three feet in length will
receive herbicide treatment and left in place; those greater than three feet in length will be
wrenched out, including as much root as is possible, and removed from the project site.
Additional weeds
In addition to the above, periwinkle has been observed scattered throughout segments A-
C. Populations of these plants will be treated at the same time as the others previously
discussed. Periwinkle will be sprayed with either glyphosate or triclopyr.
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Historic Columbia River Highway State Trail, Segments A-C Final Revegetation Plan
Roadside Revegetation: An Integrated Approach to Establishing Native Plants and Pollinator Habitat
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