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Seminars

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

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  1. 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”

  2. 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

  3. 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

  4. 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

  5. Oregon Idaho Nevada Utah Cheatgrass dominated Cheatgrass invading Cheatgrass susceptible

  6. 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?

  7. 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?

  8. 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

  9. Problem • Loss of native rangelands

  10. Why? • Invasive weeds (cheatgrass)

  11. Why? • Fires

  12. Problem

  13. Problem

  14. Problem

  15. Problem

  16. Problem

  17. Problem

  18. Problem

  19. Solution X

  20. Solution X

  21. Natives Restoration Cheatgrass How? • A transition stage • State and transition ecological model

  22. Natives Transition Cheatgrass How? • A transition stage • State and transition ecological model Natives Restoration Restoration Cheatgrass

  23. 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)

  24. Collaborative project: Oregon Idaho Nevada Utah Cheatgrass dominated Cheatgrass invading Cheatgrass susceptible • Bob Nowak UNR NRES • Bob Blank USDA ARS • Chris Call Utah State University • Jeanne Chambers USFS RMRL • Paul Doescher Oregon State University • Hudson Glimp UNR CABNR • Tom Jones USDA ARS • Nancy Markee UNR CABNR • Dan Ogle NRCS Plant Materials Center • Mike Pellant BLM Idaho State Office • Barry Perryman UNR CABNR • Dave Pyke USGS FRESC • Allen Rasmussen Utah State University • Gene Schupp Utah State University • John Tanaka Oregon State University • Robin Tausch USFS RMRL

  25. 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

  26. Izzenhood Ranch Study Site 8-10“ precipitation zone

  27. Eden Valley Study Site 10-12“ precipitation zone

  28. 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;

  29. 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'

  30. 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)

  31. 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

  32. 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

  33. 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)

  34. 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

  35. 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

  36. Benefits • Restore land health • Invasive species control • Reduce cheatgrass • Reduce secondary weeds (knapweed, • starthistle, skeletonweed) • Restoration also reduces invasibility Anderson & Inouye (2001)

  37. 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)

  38. 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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