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weather for plant establishment. Partially successful management outcomes in an
intermediate weather year may be more successful in an above-average year, and
successful management outcomes may be artifi cially elevated in an above-average
weather year. All decisions about management effectiveness, therefore, need to be
gauged relative to weather favorability, and treatments should be evaluated over a
range of weather conditions for a given climatic regime before general inferences
are assigned (Sheley et al. 2010 ; Hardegree et al. 2011 , 2012 ).
In the next two sections, we present two case studies to assess the possibilities of
integrating past research results and current land management resources within an
adaptive management framework for Bromus restoration projects in the Western
USA. In the fi rst case study, we explore how various experimental treatments impact
the abundance of B. tectorum. In the second case study, we review how the US
Department of the Interior’s Bureau of Land Management (BLM) is applying adap-
tive management for B. tectorum reduction and conservation of sage-grouse habitat
on Western USA arid and semiarid ecosystems.
12.4 Assessing B. tectorum Research : A Case Study
of Treatment Outcomes
One of the most notable characteristics shared by Bromus is their capacity to rees-
tablish from seed banks following the application of treatments. Although seeds are
generally considered short-lived and seed banks are considered transient, reestab-
lishment remains an ongoing challenge to restoration efforts (Mack 2011 ). To
address this challenge, we analyzed past research efforts to reduce B. tectorum
abundance within heavily invaded arid and semiarid ecosystems of the Western
USA. From this analysis, we identify the relative effectiveness of control treat-
ments, briefl y discuss their strengths and weaknesses, and suggest future research
needs to improve their application for adaptive management (see Sect. 12.7 ).
12.4.1 Literature Review
We identifi ed published research articles on B. tectorum control treatments using a
web-based tool (Web of Knowledge SM v. 5.9; Thomson Reuters). In our search, we
included two primary databases: Web of Science® (1975–2012) and CAB
Abstracts® (1910–2012). Using a topic search, we identifi ed all articles that con-
tained the terms downy brome, cheatgrass, Bromus tectorum , and downy chess. We
omitted articles that were not published in peer-reviewed journals; that did not
report original data from arid and semiarid woodlands, shrublands, shrubland
steppe, and grassland ecosystems; or that did not report mean values for at least one
contrast between a B. tectorum reduction treatment and an untreated control. A total
of 45 research articles, published between 1944 and 2012 (68 years), met our crite-
ria (Table 12.1 ). Among these articles, we retained those that reported percentage
T.A. Monaco et al.