This document provides information about invasive plant species in Washington County and the Tualatin Basin. It includes photos and descriptions of common invasive plants seen in the spring and summer, such as garlic mustard, yellow flag iris, purple loosestrife, and giant knotweed. The document encourages readers to learn to identify invasive plants by their flowers, leaves, growth habit, and other key characteristics. It provides information on how to report invasive plant finds and recommends actions like cleaning clothes and equipment to prevent further spread of invasives. The document aims to educate the public on invasive species in the area and how to be good stewards to prevent their invasion.

1. Robert Emanuel
Water Resources Project Manager, Clean Water Services
October 12, 2013
WASHINGTON COUNTY & TUALATIN BASIN
INVASIVE SPECIES

3. KEYS TO IDENTIFYING THE INVADERS
• Flowers
• Leaves and stems
• Habit (vine, herb, grass, rosette, etc.)
• Key characteristics (odor, reflectivity, color)
• Developing a “search pattern”

4. Looking down as you
walk, can you see the
plant’s pattern among
the others?

5. SPRING

6. GlennMiller,ODA
Garlic Mustard: Alliaria petiolata

8. GlennMiller,ODA
GlennMiller,ODAElizabethJ.Czarapata

9. Glenn Miller, ODA

13. 7-15’ tall
2-4’ tall

18. SUMMER

19. Yellow Flag Iris Iris pseudacorus
Photo:JudyScott,OSU

20. Emily DeBolt

22. Purple Loosestrife

23. Purple Loosestrife

27. GlennMiller,ODA
Giant Knotweed Fallopia sachalinese

34. EXTRA CREDIT

35. Carla Cole, NPS
Spurge Laurel: Daphne laureola

36. Carla Cole, NPS

37. Tania Siemens, TNC

38. Carla Cole, NPS

39. Yellow Archangel Lamiastrum galeobdolon
Photos:WAStateWeedControlBoard

40. Yellow Archangel Lamiastrum galeobdolon

41. Italian Lords and Ladies Arum italicum

42. Italian Lords and Ladies Arum italicum

43. Lesser Celandine Ranunculus ficaria

44. Lesser Celandine Ranunculus ficaria

45. TRUE AQUATICS

51. REPORTING YOUR FINDS
www.oregoninvasiveshotline.org

52. Only YOU can prevent
the invasion!

53. DON’T BE A VECTOR!
• Clean your clothes
• Clean your pets
• Clean your equipment & vehicle
• Walk around the infestation
• Bag/trash, burn, no compost
• If collecting voucher in flower or fruit, seal it
J.K. Linsey

54. QUESTIONS?
Partners for a Weed-Free Tualatin Basin: