415and wildfi re pose threats to rangelands. They also were more likely to hold utilitarian
versus protectionist values toward environmental stewardship. But the most impor-
tant infl uence was whether they trusted federal agencies’ ability to use grazing
effective ly as a tool. Respondents in 2006 were more likely to fi nd herbicide appli-
cation acceptable if they were less concerned about livestock impacts, held values
that emphasize the use of public lands over preservationist management, lived in
rural areas, and trusted agencies’ ability to use herbicides effectively. In 2010, the
infl uence of trust in agencies became stronger, and environmental values remained
an infl uence on acceptance of both practices, but beliefs a bout condition of and
threats to rangelands were no longer infl uential.
The fi nding that people are more likely to support using vegetation management
tools if they lean toward a utilitarian perspective on land management points to an
important infl uence on attitudes toward exotic invasive grasses—whether one
believes they have economic benefi t. For example, Marshall et al. ( 2011 ) interviewed
pastoralists across Australia about the exotic invader Pennisetum ciliare (L.) Link
(buffel grass) and found they were highly dependent on the species as forage. Eighty
percent of those surveyed believed “there is no need to worry about buffel grass from
an environmental point of view.” The authors concluded that the potential for chang-
ing cattle growers’ attitudes toward P. ciliare grass was low. Similarly, B. tectorum
may provide the vast majority of forage for cattle in the Great Basin at certain times
of year (Brunson and Tanaka 2011 ). While a study similar to Marshall and col-
leagues’ has not been conducted in the USA, Idaho ranchers have stated in workshop
settings that they believe B. tectorum can b e useful as an early season forage and thus
may not be interested in controlling the species at all locat ions (L. Salo, pers. comm.).
14.2.3 Attitude Change Research
Typically land managers want to know about attitudes because they know or suspect
that they may want to try to change those attitudes. Invasive species program man-
agers often seek ways to heighten awareness and concern about exotic invasive
plants in hopes of promoting willingness to support or engage in control activities.
Public land managers anticipating citizen opposition to a control action such as
herbicide application likewise may want to gauge attitudes and their underlying
causes in order to launch efforts to reduce that opposition. Once such efforts have
occurred, it is useful to measure whether people’s attitudes have, in fact, changed.
One way to assess attitude change is to infer it through behavior change. Marler
et al. ( 2005 ) noted that active public education efforts preceded passage of a prop-
erty tax levy in Missoula County, Montana, for exotic species control. They sug-
gested that “[t]he fact that Missoula residents would vote to tax themselves in
support of invasive plant management refl ects the amount of public support that has
developed.” Participation in volunteer weed control efforts is another example,
although these typically have revolved around broadleaf herbaceous weeds rather
than exotic invasive grasses.
14 Human Dimensions of Invasive Grasses