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the US Department of Interior’s Bureau of Land Management to restore landscapes
impacted by B. tectorum and improve greater sage-grouse ( Centrocercus urophasia-
nus ) habitat in the Great Basin region of the Western USA. We conclude that adapt-
ing for the future will require continued integration between research and
management, greater inclusion of ecological processes, and long-term experiments
to inform adaptive management decisions.
Keywords Bromus characteristics • Adaptive management framework • Treatment
outcomes • Bureau of Land Management strategies
12.1 Introduction
The evolution and proliferation of annual weeds are closely linked to human-
mediated disturbances that accompany land use. Perhaps one of the clearest exam-
ples of coevolution in agroecosystems is illustrated by the adaptation of annual
plants to frequent soil disturbance associated with land cultivation, sowing, and
harvesting activities (Palumbi 2001 ; Guglielmini et al. 2007 ). These disturbances
provided the necessary selective pressures to favor life history traits for dispersal,
colonization, and reproduction within a highly modifi ed, ruderal environment (Lytle
2001 ). Consequently, invasive annual grasses that infest Western North America are
generally preadapted to thrive in arid and semiarid ecosystems that have undergone
recurrent disturbance from dryland agriculture (Mack 1981 ; Morris et al. 2014 ),
historical overgrazing (Daubenmire 1940 ), wildfi re, energy development, urbaniza-
tion, recreational activities, and drought (Brooks and Chambers 2011 ).
While plant invasions are considered a consequence of both species traits and
ecosystem characteristics (Vilà et al. 2011 ), the impacts of exotic plant invasions on
ecological processes and functioning are context dependent (Vilà et al. 2011 ; Pyšek
et al. 2012 ). For example, many exotic species do not create ecological problems,
while others radically transform ecosystems or proliferate within areas disturbed by
human land use (Catford et al. 2012 ). For heavily invaded ecosystems, there is tre-
mendous need to broaden our understanding of how systems function through
greater integration of innovative research and holistic adaptive management frame-
works that allow iterative learning, reduce uncertainty, and support the development
of effective strategies (Herrick et al. 2012 ).
Based on a recent global assessment, ecological impacts associated with changes
in species abundance, diversity, richness of resident biota, and soil attributes were
most signifi cant if the invasive species was an annual grass with many examples
drawn from the genus Bromus (Pyšek et al. 2012 ). In accordance with this assess-
ment, exotic annual Bromus ( Bromus hereafter) invasion is impacting many arid and
semiarid ecosystems in the Western USA (Bradley et al. 2006 ; Chambers et al.
2014a ; Brooks et al. 2015 ; Germino et al. 2015 ). While the degree of invasion varies
depending on site conditions (e.g., elevation and temperature/moisture regimes), in
T.A. Monaco et al.