This document discusses invasive plant species and efforts in Delaware to promote non-invasive plants. It describes early laws passed in New England colonies in the 1700s targeting invasive barberry. It also notes the accidental introduction of the invasive Hessian fly during the American Revolutionary War. The St. Louis Declaration established voluntary guidelines for the nursery industry to assess plants for invasiveness and provide alternatives. Delaware developed an assessment tool and official invasive plant list. Outreach efforts in Delaware included publishing brochures promoting "Plants for a Livable Delaware" that are non-invasive alternatives. Surveys found the brochures increased awareness of invasives and willingness to consider recommended alternatives.

1. Invasive species and the Nursery Industry in Alaska John Peter Thompson February 2010

2. Invasive species are not a new issue local laws against growing barberry in the Americas were passed in Connecticut in 1726, Massachusetts in 1754, and Rhode Island in 1766, but enforcement of these laws lapsed as wheat declined in importance in New England Berberisthunbergii DC. – Infestation Citation: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

3. Invasive species & the founding of the United States The Hessian fly, Mayetiola destructor (Say), is one of the most destructive pest species of wheat. This insect probably originated in the southern Caucasus region of Russia and was accidently introduced into North America during the American Revolutionary War. University of Missouri Extension Citation: http://www.ars.usda.gov/images/docs/4511_4695/hessian%20fly%20poster.png

4. Invasive species create interagency challenges and diplomatic rifts Conflicting interest between new plant introductions and protection of existing ecosystems the beginnings of APHIS / Courtesy of the Fairchild Tropical Botanic Garden http://www.fairchildgarden.org/

5. Executive Order 13112 – defines an invasive species as “an alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health.”

6. St. Louis Declaration Issued December 2001 American Nursery and Landscape Association adopted - 2002 Delaware Nursery and Landscape Association adopted - 2003

7. St. Louis Declaration Ensure that invasive potential is assessed prior to introducing and marketing plant species new to North America. Invasive potential should be assessed by the introducer or qualified experts using emerging risk assessment methods that consider plant characteristics and prior observations or experience with the plant elsewhere in the world. Additional insights may be gained through extensive monitoring on the nursery site prior to further distribution. Work with regional experts and stakeholders to determine which species in your region are either currently invasive or will become invasive. Identify plants that could be suitable alternatives in your region. Develop and promote alternative plant material through plant selection and breeding.

8. St. Louis Declaration Where agreement has been reached among nursery associations, government, academia and ecology and conservation organizations, phase-out existing stocks of those specific invasive species in regions where they are considered to be a threat. Follow all laws on importation and quarantine of plant materials across political boundaries. Encourage customers to use, and garden writers to promote, non-invasive plants.

9. Plants for a Livable Delaware Faith B. Kuehn Plant Industries Administrator Delaware Department of Agriculture October 15, 2008 - Natural Areas Conference, Nashville, TN

11. Be precise about definitions

12. Using an assessment tool, develop an “official” plant list for the State

14. Definitions: Nuisance Plant (Title 3, Chapter 27 Delaware Code)“designated by Secretary of Agriculture with advice of the Nuisance Plant Committee” No person shall sell or distribute without a warning label No person who cultivates shall allow to spread onto neighboring properties

15. Invasive Plants Currently non regulatory list (9/03) Determined by: Impact on Delaware’s native species, habitats and ecosystems Current distribution and abundance Potential to spread Difficulty of management

17. effects on natural community structure and composition

18. effects on agriculture

19. conservation significance in natural areas

21. Other considerations

22. Overall invasiveness rank = 0-12

24. Incentives to Participating in Voluntary Programs* *Biological Invasions, 2007

25. Obstacles to Participating in Voluntary Programs* *Biological Invasions, 2007

27. Ecologically

28. Many industries involved

29. Need to consider aesthetic

30. Nursery industry needs to embrace sustainable view

31. Need to address supply and demand

33. Noxious weed vs. invasive vs. nuisance

34. What is invasive locally and boundaries

35. Must affect plant supply & demand

36. Resources required to enforce

37. Limited set of control options

39. Legislation is reactive, no pro-active

40. Impact on green industry

41. Screening mechanism for new plants

42. Grandfathered plants?

43. Legislation not always positive message

44. Remove invasive & replace with what??

46. Be precise about definitions

47. Using an assessment tool, develop an “official” plant list for the State

50. Pose no potential threat as an invasive plant

51. Have no serious disease or insect problems

53. Printed 2004 3 printings 40,000 copies FUNDING: National Fish & Wildlife Foundation Delaware Estuary Program

54. Issued 2005 1 Printing 15,000 copies FUNDING: National Urban and Community Forestry Advisory Council

55. Issued 2006 1 printing 15,000 copies FUNDING: Northeastern Area State and Private Forestry, U.S. Forest Services

56. Issued: 2006 2 printing 3,000 copies FUNDING: Delaware Department of Agriculture

57. January 2009 5,000 copies, originally reprinted by NRCS Funding: Delaware Natural Resources Conservation Service

58. Survey results Brochure was very easy (55%) or easy (21%) to understand – 76% of respondents 90% had never seen brochure, but 62% knew about invasive plants 71% have one or more of the invasive plants described in brochure on their property

59. Survey results 29% were planning to purchase an invasive plant 82% would now consider purchasing a “Livable Delaware Plant” as an alternative

60. Photo: Gary Schwetz