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14.2.1 Beliefs about Exotic Invasive Plants
and Management Options
Some scholars have argued that exotic invasive species impose huge conservation or
economic costs on society (Wilcove et al. 1998 ; Mack et al. 2000 ; Pimentel et al.
2005 , but see also Davis et al. 2011 ). However, when citizens consider the full range
of risks to natural environments, exotic invasive species often do not rank very high.
Slimak and Dietz ( 2006 ) surveyed members of the public as well as selected US
environmental professionals and asked them to rank 24 ecological risk items from
climate change to hazardous wastes to sport hunting and fi shing. Among the lay
public, invasive species ranked 19th, just behind overgrazing and ahead of damming
rivers but well below the greatest perceived risks: hazardous waste sites and persis-
tent organic pest icides. The mean rank was 15 for an “experienced public” sample
who had participated in US Environmental Protection regional assessments.
Professional risk assessors ranked invasive species as ninth most critical of the 24
risks, suggesting that beliefs about the threat of exotic invasive species are highly
infl uenced by knowledge and experience. In another survey of persons to whom the
exotic invasive species issue should be especially salient, just 62 % of Minnesota
nursery and landscape industry professionals said invasive plants are an important
issue (Peters et al. 2006 ). Economic concerns may have tempered risk assessments
in this group, as just 69 % said they would not sell a plant if they knew it was poten-
tially invasive, and 57 % said they would not sell an invasive plant even if they knew
a competitor was selling it (Peters et al. 2006 ).
Looking more specifi cally at exotic species affecting wildlands in the Western
USA, where Bromus invasion is of specifi c concern, Tidwell ( 2005 ) surveyed resi-
dents of 11 counties with active weed education programs in Arizona, Colorado,
New Mexico, and Utah about their beliefs regarding invasive plants and their man-
agement. In this survey, 94 % of respon dents indicated that they were concerned
about invasive plants. When asked about specifi c threats posed by exotic species,
the impacts of greatest concern were increased wildfi re danger, reduced quality of
wildlife habitat, and loss of native plants. A series of surveys in the Great Basin
states of Idaho, Nevada, Oregon, and Utah (Shindler et al. 2011 ; Gordon et al. 2014 )
found that in 2010 more than 83 % of respondents believed invasive species pose a
threat to healthy rangelands, a 9 % increase over 2006. Another survey in Utah and
Idaho found that nearly all r espondents were at least moderately concerned about
negative effects of invasive plants, and most said controlling plants on their own
properties was important (Christensen 2010 ).
In one of the few studies to ask specifi cally about Bromus , Kelley et al. ( 2013 )
measured ranchers and natural resource professionals’ perspectives on managing
B. tectorum in Colorado and Wyoming. Both groups thought the species is a prob-
le m in that area, although for the most part ranchers were less concerned than natu-
ral resource professionals. Overall, 51 % of ranchers in the sample perceived
B. tectorum to be a moderate to severe problem, while 18 % felt it was not a prob-
lem at all; among natural resource professionals, 66 % perceived B. tectorum to be a
M.W. Brunson and H. Kartchner