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Waging war on Invasive Grasses: Preventing – Not just Controlling –
Rangeland Fires in the West”
Richard N. MackSchool of Biological SciencesWashington State University
Pullman, WA 99164 [email protected]
http://www.sbs.wsu.edu/mack/mack.htm
Medusahead Cheatgrass Buffel grass
Destruction of huge areas is common
The cheatgrass invasion didn’t occur overnight
Circa 1900
Mack (1981) Agro-Ecosyst. 7: 145
Mack (1981) Agro-Ecosyst. 7: 145
By 1930 cheatgrass had occupied its current range
“Waging war on cheatgrass” and other invasive grasses
Despite efforts of many for decades; they are firmly entrenched
A truly national issue –power generation in the PAC NW
“Waging war on invasive grasses”
Where do we (can we) go from here in successfully combating these invaders?
Where success means reducing their extent and impact (and even restoring Intermountain West grasslands to some semblance of a natural system)?
Contention:Needed for success in “Waging war on invasive grasses” are new tools, tactics and strategies
Strategy: “the art of projecting and directing the larger military movements and operations of a campaign”
Tactics: “the art of handling the spread of handling forces in battle or in the immediate presence of the enemy”
Tools: Effective tools can come in some surprising forms; must be appropriate for the task
New tools, tactics, and strategies
A little history from a different time, different place, and with different goals
GOAL: Build a Canal – Across Central America
Strategy: build a sea-level canal improvise “on the fly”Failed strategy: woefully underestimated the size of the project as envisioned
Tactics: excavate multiple locations simultaneously
Tactics: right idea, but became irrelevant because of other failed components
Tools: many types of equipment; all unsuited for the task (e.g. Slaven excavators)
The Result:
A poorly thought out strategy, and poorly suited tools doomed the project, rendering the tactics irrelevant.
All three elements in pursuit of a large goal must be strong.
U.S. Government (1904-1914)
Strategy: Advanced planning before launching excavation concluded that a
system of canal locks was needed
Tactics: excavate multiple locations simultaneously; mid-course corrections; deal aggressively with disease
Tools: Uniform equipment: huge steam shovels and portable RR system
The result of sound strategy, flexible tactics and effective tools – goal achieved!
Developing a new strategy, tactics and tools for combating invasive grasses, where the goal is to greatly reduce their range and
abundance (and resultant impact).
New tools: detect, identify and develop microbial bio-control agent(s). These grasses are not abundant in their native range. What restricts them elsewhere?
Among successful biocontrol programs, some employ microorganisms
Control of rubber vine (Cryptostegia grandiflora) by Maravalia cryptostegiae (rubber vine rust); reduces flowering, seed pod & leaf production
New Tools:
Greatly expand knowledge of the genetic variation in cheatgrass and other invasive grasses.
Cheatgrass native range
Extensively evaluate potential microbial biological control agents:
Ustilago bullata
Pryrenophora semenipera
Pseudomonas flourescens strain D7
New Tools: Characterization of the generic variation (and sources) of genotypes of these grasses and potential microbial biological control agents has now become practical!
e.g. 454 gene sequencer
New Tools: Restore (and routinely maintain) the cryptobiotic crust
N-fixationReduce surface
erosionMulch Thwart
cheatgrass seedling establishment!
New Tools:
Develop means to rapidly and routinely re-establish cryptobiotic crust
Current Tools (new emphasis) & New Tactics
• Great Basin Native Plant Selection • BLM Seeds of Success Program• Increased restoration of grasslands, including planting (not
solely seed) woody plants and plugs of native grasses (not just sowing native seeds)
New Strategy: restore native grasslands, not only fight fires