1. 5)Management c)Control iii)Biological methods = “biologically” damaging plants

2. 5)Management c)Control iii)Biological methods = “biologically” damaging plants Biotic constraints/enemy release hypothesis

3. 5)Management c)Control iii)Biological methods = “biologically” damaging plants Biotic constraints/enemy release hypothesis If plants are invasive because they have escaped natural enemies, introducing the natural enemies should help control the invasive!

4. 5)Management c)Control iii)Biological methods Least public opposition

5. 5)Management c)Control iii)Biological methods Least public opposition Recall Federal Plant Protection Act : Biological control is often desirable

6. 5)Management c)Control iii)Biological methods Least public opposition Recall Nevada noxious weed legislation: Weed control analyst researches biological control options

7. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia W. Wagner@USDA-NRCS Plants Database

8. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia Chronology (source: http://www.northwestweeds.nsw.gov.au )http://www.northwestweeds.nsw.gov.au W. Wagner@USDA-NRCS Plants Database

9. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia Chronology (source: http://www.northwestweeds.nsw.gov.au )http://www.northwestweeds.nsw.gov.au Introduced in 1788 with the First Fleet – dye industry Additional introductions for forage and hedges though 1800s Numerous species Problem acknowledged 1870 W. Wagner@USDA-NRCS Plants Database

10. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia Chronology (source: http://www.northwestweeds.nsw.gov.au )http://www.northwestweeds.nsw.gov.au Introduced in 1788 with the First Fleet – dye industry Additional introductions for forage and hedges though 1800s Numerous species Problem acknowledged 1870 1886: prickly pear destruction act 1910: ‘Roberts Improved Pear Poison’ created – 80% sulfuric acid, 20% arsenic – considered best weapon

11. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia Chronology (source: http://www.northwestweeds.nsw.gov.au )http://www.northwestweeds.nsw.gov.au Early chemical control: fumes from boiling arsenic Photo: © L. R. Tanner

12. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia Chronology (source: http://www.northwestweeds.nsw.gov.au )http://www.northwestweeds.nsw.gov.au Early chemical control: boiling arsenic 1912 problem rampant: begin looking for biological control

13. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia Chronology (source: http://www.northwestweeds.nsw.gov.au )http://www.northwestweeds.nsw.gov.au Early chemical control: boiling arsenic 1912 problem rampant: begin looking for biological control Photo: © L. R. Tanner

14. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia Chronology (source: http://www.northwestweeds.nsw.gov.au )http://www.northwestweeds.nsw.gov.au Early chemical control: boiling arsenic 1912 problem rampant: begin looking for biological control 1925, infested twenty-five million hectares in New South Wales and Queensland. It was spreading at the rate of half a million hectares a year.

15. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia Chronology (source: http://www.northwestweeds.nsw.gov.au )http://www.northwestweeds.nsw.gov.au 1926 introduction of Cactoblastis moth Photo: © L. R. Tanner

16. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia Chronology (source: http://www.northwestweeds.nsw.gov.au )http://www.northwestweeds.nsw.gov.au 1926 introduction of Cactoblastis moth By 1932, most of the prickly pear stands had been decimated. Photo: © L. R. Tanner

17. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia Chronology (source: http://www.northwestweeds.nsw.gov.au )http://www.northwestweeds.nsw.gov.au 1926 introduction of Cactoblastis moth By 1932, most of the prickly pear stands had been decimated Photo: © L. R. Tanner

18. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia Summary: spectacularly successful BUT Took 14 years to find biocontrol agent (1912-1926) Some cool-climate stands remained; insect less effective

19. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Prickly pear (Opuntia spp.) in Australia Summary: spectacularly successful BUT Took 14 years to find biocontrol agent (1912-1926) Some cool-climate stands remained; insect less effective Opuntia aurantica becomes more problematic 1930-1950

20. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Klamath weed (Hypericum perforatum) in California

21. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Klamath weed (Hypericum perforatum) in California Broad-leaved, perennial herb Introduced from Europe in 1793; reached California late 1800’s Extremely invasive; toxic By early 1940’s: 5 million acres of infested rangeland Biological control in California: 1945-1950 @ $750,000 total cost By early 1960’s insects had reduced acreage to <1% of peak

22. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Tamarix in western US: Photos: Bob Conrad, NAES

23. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Tamarix in western US: SourceL Swedhin et al. 2006 (Tamarisk Research Conference, Fort Collins CO) Large scale dispersal and population expansion of Diorhabda elongata in CO, NV, and UT after initial releases Near Moab: two release sites in 2004. In 2005, less than 2 acres of tamarisk defoliated. In 2006, 109 acres defoliated, 4.1 miles upstream from release sites and area was expanding Expansion of beetles from UT release sites on Colorado River into CO expected by summer 2007

24. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations:

25. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Finding an enemy

26. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Finding an enemy ID promising species in native range Test for host specificity USDA has facilities in other countries for this purpose http://www.ars-ebcl.org/

27. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Finding an enemy ID promising species in native range Test for host specificity USDA has facilities in other countries for this purpose http://www.ars-ebcl.org/ e.g. Montpelier, France Photo © USDA ARS-EBCL Current projects: Canada Thistle, Field Bindweed Giant reed, Knapweeds, Leafy Spurge, Lepidium draba, Rush Skeletonweed, Saltcedar, Swallow- worts, Yellow Starthistle

28. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Finding an enemy ID promising species in native range Test for host specificity USDA has facilities in other countries for this purpose http://www.ars-ebcl.org/ e.g. Montpelier, France Also Rome, Italy and Thessaloniki, Greece Photos © USDA ARS-EBCL

29. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Finding an enemy Host specificity: specialists not generalists

30. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Finding an enemy Host specificity Mode of action (plant part affected)

31. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Finding an enemy Host specificity Mode of action (plant part affected) Type of organism (disease, insect)

32. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Finding an enemy Host specificity Mode of action (plant part affected) Type of organism (disease, insect) Climate requirements of organism (climate matching for source populations and introduction sites) e.g. some releases of Diorhabda from Texas populations not successful at higher latitudes – couldn’t overwinter

33. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Finding an enemy Host specificity Mode of action (plant part affected) Type of organism (disease, insect) Climate requirements of organism (climate matching for source populations and introduction sites) Estimated that about ½ of introduced weed bio-control insect species establish in new location

34. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Finding an enemy Non-target effects

35. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Finding an enemy Non-target effects Specificity of biocontrol agent Relatedness of flora

36. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Non-target effects – Pemberton (2000)

37. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations: Non-target effects

38. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations Non-target effects

39. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations Non-target effects

40. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations Non-target effects

41. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations Non-target effects

42. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations Non-target effects

43. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations Non-target effects

44. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations Non-target effects

45. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Difficulty locating enemy Non-target effects – From Pemberton (2000)

46. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Difficulty locating enemy Non-target effects – From Pemberton (2000)

47. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations Non-target effects

48. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Considerations Non-target effects

49. 5)Management c)Control iii)Biological methods Least public opposition Number of success stories Difficulty locating enemy Non-target effects Most likely a problem when the invasive species has closely related plants in the invaded area