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Useful resources

Web sites
ISI list of links (of course)
University of Arizona's Rangeland Management Website
Center for Grassland Studies, University of Nebraska
Society for Range Management
Soil and Water Conservation Society
Grazing Management: An Ecological Perspective
Rangeland Watershed Program Fact Sheets, University of California
Livestock and the Environment: Finding a Balance
National Library for the Environment, Congressional Research Service Reports
Sustainable Ranching Research and Education Project

  • The Invasive Species Team listserve can be joined by emailing Barry Rice (bamrice(at)ucdavis.edu). Archives for this listserve can be viewed here.
  • The Aridlands Network Listserv focuses on conservation issues specific to the arid western U.S., especially those related to ranching, grazing, and invasives. It provides a forum for exchanging information, asking questions, offering advice, and announcing events and funding opportunities. The list is also the primary communication vehicle for Aridland Network updates and announcements. Anyone interested in grazing or ranching issues is welcome to join. Contact Bob Unnasch at bunnasch(at)tnc.org or 208-343-8826 to subscribe.
Virtual Fencing
Virtual fencing combines Global Positioning System (GPS) technology and electro-mechanically produced bilateral cues in a new paradigm to control free-ranging animal location and direction of movement in a humane and reproducible manner in real-time. The only ground-based hardware is the device worn by the animal in which a central processing unit uses radio frequency signals captured from GPS satellites to determine the animal's location.

The USDA-ARS Jornada Experimental Range (JER)'s Virtual Fencing Research Program has published several papers and Web sites with detailed information about virtual fencing:
  • Article on the USDA-ARS JER's Virtual Fencing research program published in the November 2000 issue of Agricultural Research.
  • A paper presented at the Tracking Animals with GPS conference held March 12-13, 2001 in Aberdeen, Scotland (see pages 85-94).
  • An overview of current research on virtual fencing technology.
For more information about the research program at the USDA-ARS JER contact:

Dr. Dean M. Anderson
USDA-ARS Jornada Experimental Range
Range Management Research Unit
Las Cruces, NM 88003

Weed Prioritization Tool
Land managers are often confronted by a wide variety of invasive plant species and numerous complex weed management situations. Furthermore, there are always more weed management problems than available resources. To ensure that management efforts are well focused and cost-effective, it is important to prioritize specific weed species and infestations according to their magnitude and the threat they pose to uninfested lands and desirable natural resources.

This simple tool provides a framework for prioritizing local weed management issues and directing resources towards some weed management problems that can be resolved quickly while minimizing the destructive potential of other problems. This example is from Boulder County, Colorado but the tool can be adapted to address weed management challenges in different locations.

Invasive Weeds Database
The Conservancy and the Bureau of Land Management have developed an invasive weeds database for tracking invasive species occurrence data, current status, and treatment information. Field data collected with hand-held electronic data recorders can be easily downloaded into the database. Steve Buttrick (TNC) gave a presentation about the database at the network's second workshop in September 2002. For more information contact Steve (sbuttrick(at)tnc.org), Nathan Rudd (nrudd(at)tnc.org), Mandy Tu (imtu(at)tnc.org), or Barry Lavine (blavine(at)usa.net).

(Update: This database application can now be downloaded from the GIST web site here!)

Summary of Aridlands Grazing Workshop #1
The primary goal of the network's first workshop was to review the underlying scientific framework for conservation at each of the focal landscapes, focusing in particular on the role of grazing as a conservation tool. The summary provides an overview of the meeting's plenary talks on (1)the role of grazing in the Conservancy, (2)the ecological effects of grazing, and (3)socio-economic issues in the arid West and how they relate to conservation of ranchlands. It also highlights the best practices and lessons learned that were identified during the meeting.

Summary of Aridlands Grazing Workshop #2
The second workshop focused on identification of key conservation strategies that will effectively abate threats and achieve desired future landscape status. The summary provides an overview of the meeting's plenary talks on (1)grazing as a tool for managing exotic species, (2)grazing as a tool for protecting biodiversity, and (3)cheatgrass, livestock management, and restoration in the Great Basin Desert. It also highlights the best practices and lessons learned that were identified during the meeting.

Vegetation Dynamics Development Tool
The Vegetation Dynamics Development Tool (VDDT) is a computer-based modeling framework for examining the role of succession, disturbances, and management actions in vegetation change. The Windows-based program allows users to easily create and test descriptions of vegetation dynamics, simulating them non-spatially at the landscape level.

VDDT assumes that the landscape has been stratified into units with similar successional regimes, or pathways. The default convention is that this stratification identifies potential vegetation types (PVTs). Within each PVT, vegetation states are defined as combinations of the predominant cover type and structural stage, called successional classes. Movements between classes are described by two types of pathways: (1) changes driven by disturbances, and (2) changes due to stand dynamics in the absence of disturbance (e.g., regeneration, growth, and self-thinning).

Disturbance-related pathways specify, for each class, the type of disturbance, its probability (which defines the return frequency), and its impact on vegetation. Changes due to stand dynamics are defined by the time a stand remains in a structural stage (or cover type) and by the successional class it will move to after this time has elapsed.

VDDT was developed by ESSA Technologies, and can be downloaded from (http://www.essa.com/downloads/vddt/download.htm). For additional information, contact Don Robinson at drobinson(at)essa.com or (604) 733-2996.

Tool for Exploratory Landscape Scenario Analyses (TELSA)
TELSA is a spatially explicit model of terrestrial succession, natural disturbances, and management activities. It represents succession and the impacts of management and natural disturbances as changes in species composition and structural stages of stands. Diagrams developed with the Vegetation Dynamics Development Tool (VDDT) define the transition times between various succession classes (combinations of species composition and stand development stage); and the probabilities and impacts of disturbance by insects, fire, or other agents. These diagrams also define the impacts of management actions on stand structure and composition.

Forest management, including salvage logging, is also defined by specifying which actions to schedule based on the condition of stands and of the landscape. TELSA includes an automated approach to designing management units based on user-specified criteria. It can therefore be used to assess alternative size ranges for management units and mixtures of management systems.

TELSA was developed by ESSA Technologies. For additional information, contact Don Robinson at drobinson(at)essa.com or (604) 733-2996.

Information about the WILN Workshops #1-2 and the upcoming Workshop #3 to be held in October 2005 in Grand Junction, Colorado. Information from past Aridlands Grazing Workshops #1-5 are also archived here.

Participating site information
Approximately fifty conservation areas have participated in both the WILN and its progenitor, the Aridlands Grazing Network. Here you can find detailed information about many of these conservation areas, including general descriptions and management tools (e.g., conceptual ecological models).

Updated February 2005
©The Nature Conservancy, 2003