Revegetation Guidelines for Western Montana - Global Restoration ...

4. Restore a healthy plant community – Weed-infested sites alter the structure,
organization, and function of ecologic systems (Olson 1999). The development of a healthy
plant community comprised of functionally diverse species is the key to sustainable invasive
weed management while meeting other land use objectives such as forage production, wildlife
habitat development, or recreational land maintenance (Sheley et al. 1996).
The development of a healthy plant community involves long-term management that includes
steady removal of individual weeds with replacement by desired plants. This replacement can
occur as natural revegetation, when desired vegetation cover and propagules are adequate
within the infestation, or through revegetation efforts. Species selection to restore a desired or
healthy plant community should follow recommendations in the previous section and other
recommendations specific to intended use of the site.
It will be imperative to protect the remnant native forb component within the weed-infested site
during weed management. This may be difficult to attain, as the preferred choice of infestation
management is typically broadcast herbicide treatments that often injure or permanently damage
remaining native forbs. However, site-specific methods should be developed and employed to
protect remnant forbs, such as through careful herbicide spot treatments. Forb protection within
weed-infested sites is important, as this component is vital to ecosystem stability and key to longterm
weed management success given forbs have demonstrated strong competitive abilities with
invasive weeds (Pokorny 2002). Also, the protection of remaining forbs is beneficial as this
component is very difficult and expensive to reestablish relative to a grass component.
Following the development of a healthy plant community, long-term maintenance that favors
the seeded species will be necessary. The desired grass component should be managed to
encourage strong vigor and growth, such as avoiding heavy grazing practices, and the forb
component should be managed to encourage highest levels of diversity, such as through
periodic prescribed burning.
Site Characteristics
Once species have been selected to meet revegetation goals and management objectives, site
characteristics such as soil attributes and the precipitation, soil moisture, temperature, and elevation
can confirm species selection.
Soil attributes
Soil texture, determined by the size of the particles that comprise the soil, is an important soil
characteristic that can direct species selection. Most seeded species prefer medium- to finetextured
soils. However, Indian ricegrass, a highly drought-tolerant native bunchgrass, is
well adapted to sandy soils, and western wheatgrass, a native rhizomatous grass, does well
on heavier, clay soils. Loam is usually the optimum soil texture comprised of 45 percent
sand, 35 percent silt, and 20 percent clay (Figure 2). See text box to generally determine
your soil type. For large or challenging projects, consider obtaining a soil survey map from
your local USDA Natural Resources Conservation Service Field Office.
You can roughly estimate the approximate amount of sand, silt and clay in soil by a simple
method called "manual texturing." The feel of the moist sample when rubbed between the thumb
and forefinger determines the texture. If the soil sample is predominantly sand, it will feel very
Tcoarse and gritty. If it is predominantly silt, it will feel smooth or slippery to the touch. And if it is
e predominantly clay, it will feel sticky and fine in texture.
21