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Seminars. “Plant Talk” – Thurs April 8 12:00 PM in FA 214. Eric Petersen: “ Using remote sensing to estimate the distribution of cheatgrass in Nevada.”

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Seminars

  • “Plant Talk” – Thurs April 8 12:00 PM in FA 214. Eric Petersen: “Using remote sensing to estimate the distribution of cheatgrass in Nevada.”

  • EECB Colloquium OSN 102 at 4:00 PM Thursday April 8. Graham Hickling, Michigan State. "Emerging Disease in Wildlife Populations: Bovine Tuberculosis as a Case Study”


Reading

  • D’Antonio, C., and Vitousek, P. 1992. Biological invasions by exotic grasses, the grass fire cycle, and global change. Ann. Rev. Ecol. Syst. 23: 63-87.

  • FYI: Pellant, M. 1996. Cheatgrass: the invader that won the West. BLM Interior Columbia Basin Ecosystem Management Project report: http://www.icbemp.gov/science/pellant.pdf


Outline

  • Extent of cheatgrass invasion

  • Distribution and history of invasion

  • Why is cheatgrass a good invader?

  • What are the problems?

  • How can we reverse the process?

  • “Integrating weed control and restoration” project

  • Discussion


Extent of cheatgrass invasion in Great Basin

  • Bromus tectorum dominates 3 million acres

  • Another 14 million acresare invaded

  • 60 million acres are vulnerable to invasion


Oregon

Idaho

Nevada

Utah

Cheatgrass dominated

Cheatgrass invading

Cheatgrass susceptible


Origin and history

  • Bromus tectorum originally from SW Asia and middle east

  • Introduced as contaminant in wheat seed

  • First records in southern BC, eastern Washington

  • Spread quickly, but didn’t become dominant. Current distribution reached by around 1930.

  • Why could it invade and become dominant?


Why could invasion occur?

  • Opportunistic

  • Prolific seeder

  • Plastic life history (winter or spring annual)

  • Good competitor

  • Somewhat grazing tolerant

  • Changes fire regime

  • “pre-adapted” to cold desert conditions

  • Suppression of native community by grazing?


What is the problem?

  • Loss of perennial species and wildlife habitat

  • Increase in fire frequency (damaging and costly)

  • Hard seeds injure stock

  • Good fodder for short period only


Problem

  • Loss of native rangelands


  • Why?

  • Invasive weeds (cheatgrass)


  • Why?

  • Fires


Problem


Problem


Problem


Problem


Problem


Problem


Problem


Solution

X


Solution

X


Natives

Restoration

Cheatgrass

How?

  • A transition stage

    • State and transition ecological model


Natives

Transition

Cheatgrass

How?

  • A transition stage

    • State and transition ecological model

Natives

Restoration

Restoration

Cheatgrass


Rangeland restoration project

  • First – identify promising commercially available species and varieties for restoration planting (Experiment 1)

  • Second – investigate competitive ability of cheatgrass and planted native community. Close the open niche for cheatgrass (Experiment 2)

  • Third – demonstrate management options on larger scale (Experiment 3)


Collaborative project:

Oregon

Idaho

Nevada

Utah

Cheatgrass dominated

Cheatgrass invading

Cheatgrass susceptible

  • Bob Nowak UNR NRES

  • Bob BlankUSDA ARS

  • Chris CallUtah State University

  • Jeanne ChambersUSFS RMRL

  • Paul DoescherOregon State University

  • Hudson GlimpUNR CABNR

  • Tom JonesUSDA ARS

  • Nancy MarkeeUNR CABNR

  • Dan OgleNRCS Plant Materials Center

  • Mike PellantBLM Idaho State Office

  • Barry PerrymanUNR CABNR

  • Dave PykeUSGS FRESC

  • Allen RasmussenUtah State University

  • Gene SchuppUtah State University

  • John TanakaOregon State University

  • Robin TauschUSFS RMRL


  • Experiment 1: agronomic trials of drill-seeded species

  • Thurber’s needlegrass – Orchard

  • Bluebunch wheatgrass – Goldar, Anatone, P-5

  • Thickspike wheatgrass – Critana, Bannock

  • Snake River wheatgrass – Secar, KBJ

  • Squirreltail – Sand Hollow, 2nd accession

  • Indian ricegrass – Nezpar, Rimrock, Rimrock HG

  • Basin wildrye – Magnar, Trailhead, NV MOPX

  • Bluegrass – Sherman, High Plains, Mountain Home

  • Crested wheatgrass – Vavilov, CD-2

  • Wheat sterile hybrids (3 varieties)

  • Plants of local interest – Shadscale, winterfat

  • Globemallow


Izzenhood Ranch Study Site

8-10“ precipitation zone


Eden Valley Study Site

10-12“ precipitation zone


Experiment 1 procedure

  • Drill-seeded into 10’ by 20’ trial plots, 6 blocks at each study site. Planted November 2003.

  • 3 blocks sprayed with post-emergent herbicide, 3 not sprayed

  • Growth, survival, biomass of planted species will be monitored.

  • Results so far – differences among emergence rate of different accessions;


390'

50'

Herbicide application

50'

50'

50'

410'

Individual study plots with varietal seeding randomly assigned. Each plot has 10 rows with 1‘ row spacing.

20'

10'

70'

10'

10'

120'


Experiment 2

  • Seed monocultures of accessions, native species mix (6 species with range of growth forms) + cheatgrass

  • Add labile carbon (sucrose) to ½ plots to sequester N

  • Monitor emergence, growth and survival of both planted species and cheatgrass

  • Preliminary results – carbon addition appears to reduce emergence of both natives and cheatgrass, but cheatgrass suppressed more (3X)


Experiment 2

Reduce soil nitrogen

  • Cheatgrass inhibited by low soil nitrogen,

    Natives are tolerant of low nitrogen

  • Soil amendments to tie up nitrogen

  • Mix of natives to deplete resources

    sagebrush, yarrow, globe mallow, bluegrass

    squirreltail, bluebunch wheatgrass


300'

Herbicide application

Sugar application

No sugar

15 m

350'

15 m

15 m

Individual study plots with seeding treatments randomly assigned

15 m

1.5 m

2.5 m

15.5 m

2 m

2 m

2 m

2 m

23 m


Experiment 3

  • Demonstration of potential management techniques on larger scale (3 ha)

  • To be implemented Autumn 2004

  • Location – Biddell Flats (25 miles north of Reno)


How?

  • A transition stage

  • Reduce soil nitrogen

  • Large-scale restoration trials

    • Transition community vs. Native mix

    • Restoration treatments targeted at:

      • reduce cheatgrass seedbank

      • reduce soil N

  • Treatments:

    • Control – no treatment

    • Burn-seed-burn-seed: to reduce cheatgrass seedbank.

    • Transitional community. Sterile hybrid.

    • Grazing to reduce cheatgrass seed set

    • Herbicide (‘gold standard’ for control)

    • Burning and grazing combination


  • 200 m

    200 m

    100 m

    5,250'

    Mixed

    species

    Best

    accessions

    Control

    Burn-Seed-Burn-Seed

    Herbicide

    4,140'

    100 m

    100 m

    Grazing

    Burn-Graze

    15 m spacing


    Benefits

    • Restore land health

    • Invasive species control

      • Reduce cheatgrass

      • Reduce secondary weeds (knapweed,

        • starthistle, skeletonweed)

    • Restoration also reduces invasibility

    Anderson & Inouye (2001)


    My research

    • What makes rangeland invasible in the first place?

    • Common knowledge – shrub steppe is resistant to invasion

    • unless overgrazed.

    • BUT – cheatgrass is “pre-adapted” to cold desert conditions

    • - there are few native annual species (vacant niche?)

    • - there is a large amount of empty space even in healthy

    • community

    • - resources are variable; could pulsing of resources allow

    • invasion?

    • Greenhouse studies (individual plant performance, mesocosms,

    • field test)


    Questions for discussion

    • What principles of ecology are we applying?

    • How does understanding ecology of the system help

    • the design and interpretation of the experiment?


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