Download - Alien Invaders!!
Alien Invaders!!
Impacts of Invasive Plant Species in Oregon
Erin Tirone
Road Map
• Definitions• Examples of Invasive Species
– Description– Impacts on native landscape
• Eradication Methods– Pros/cons
• Questions
What does it mean to be…?
• Native– A plant or animal originating from a particular
place or region
• Endemic– Native to or confined to a certain region
• Invasive– Marked by a tendency to spread– Tendency to intrude or encroach
Why do plants become invasive?
• “New” environment similar to native environment
• Better competitors than the natives
• Efficient adaptations
• No natural predators in “new” environment
• Opportunistic
Himalayan Blackberry
• Native to Eurasia, pervasive in Oregon
• Spreads rapidly through underground growth and seed dispersal
• Establishes itself in sunny disturbed areas
English Ivy
• Europe native• Spreads by extension
of runners• Many negative
impacts on plant and habitat diversity
• Attempts at mitigation in Forest Park
Reed Canarygrass
• Native for Europe and Asia (though still being debated whether it is actually native to North America)
• Spreads through rhizomes and seed dispersal
Scotch Broom
• Scotland native• Grows on open,
sunny, disturbed sites• Produced enormous
amount of seeds, which are viable for up to 80 years
Japanese Knotweed
• Introduced from Asia, perhaps as ornamental plant
• Grows through rhizomes
• Establishes itself in moist ravines, ditches, and disturbed areas
Morning Glory
• Eurasian native• Grow in disturbed
areas, commonly found along waterways, fields and roadsides
• Grow from rhizomes, are ground creepers
Clematis
• Common in disturbed open canopy areas
• Spread through wind dispersal of seeds from wispy flowers
Common Methods of Eradication
• Pulling out the roots
• Cutting canes (blackberry)
• Soil solarization
• Planting Native plants
• Herbicide application– Spraying– Spot application
Works Cited
• Invasive and Exotic Species of North America. 2002. USDA Forest Service. http://www.invasive.org
• Invasive Plants--A Guide for Dealing with Non-native Species. Beaverton, OR: Natural Resources Office, Tualatin Hills Park and Recreation District
• Pojar, J. & A. MacKinnon. 1994. Plants of the Pacific Northwest Coast. Vancouver, B.C.: Lone Pine.
• Reed Canyon Enhancement Strategy. Non-native Species Management. 2001. Portland, OR: Reed College. http://web.reed.edu
• Taylor, R.J. 1990. Northwest Weeds. Missoula, MT: Mountain Press.