Transcript Purple Loosestrife - Earth Systems Education

Photo: Paula McIntyre GLIFWC
Purple Loosestrife
Lythrum salicaria
Purple Loosestrife
What is it?
Photo: Paula McIntyre GLIFWC
 Purple loosestrife (Lythrum salicaria) is an Non-Indigenous
plant species and an Aquatic Nuisance Species
 What are Non-Indigenous Species (NIS)?
 Non-Indigenous Species (NIS) - organisms that have moved beyond their
natural geographic range of habitat
 NIS can be microorganisms, plants or animals
 NIS can be terrestrial or aquatic
 What are Aquatic Nuisance Species (ANS)?
 Aquatic Nuisance Species (ANS)- are NIS that threaten the native species,
ecological stability, commercial, agricultural, aquacultural, or recreational
activities that depend on the infested waters.
 ANS can occur in inland, estuarine and marine waters
Purple Loosestrife
How did it get to the U.S.?
Photo: Paula McIntyre GLIFWC
Arrived in eastern North America in the early 1800’s
 Intentional
 Plants brought by settlers for their flower gardens and herbal uses
 Unintentional
 Seeds may have been transported in livestock feed or bedding
 Seeds were present in soil in the ballast holds of European ships
 Ballast –used by ships to weigh down vessels for stability on the
ocean
 Early European ships used soil, which may have contained the
seeds
 Modern ships use water
http://www.nsf.gov/od/lpa/forum/colwell/rc02abelwolman/sld026.htm
Purple Loosestrife
What does it look like?
Photo: Paula McIntyre GLIFWC
 Flowers:
 Purple to magenta in color
 5-6 petals
 Bloom in long spikes
 Leaves:
 Green, lance-shaped
 Opposite along the stem
 Stem:
 Dense, woody
 Square, 4-sided
http://www.npwrc.usgs.gov/resource/1999/loosstrf/field.htm
Purple Loosestrife
Where does it live?
Photo: Paula McIntyre GLIFWC
 Moist soil to shallow water
 Wet meadows and pastures
 Marshes and wetlands
 Stream and river banks
 Lake shores
 Roadside ditches
 Can tolerate drier conditions
 Lawns and gardens
 Agricultural and pasture land
http://www.dnr.state.wi.us/org/land/er/invasive/info/loose2.htm
Purple Loosestrife
How does it spread?
Photo: Paula McIntyre GLIFWC
 Naturally
 One mature plant can produce approximately 2.5 million seeds per
year, high germination rate (almost 100%)
 Small, lightweight seeds can be dispersed by wind, animals, storm
water runoff
 Seeds remain viable for many years underwater or in soil
 Can regenerate from roots or cuttings of other plants
 Humans
 Carried on clothing or vehicles
 Planted in ornamental gardens and by bee keepers
 Roadside mowing
http://www.agric.gov.ab.ca/images/pests/ weeds/purpleloose7.jpg
Purple Loosestrife
What does it do?
Photo: Paula McIntyre GLIFWC
 Invades wetlands
 Out-competes and replaces native plants
 Eliminates natural food and cover for wildlife
 Can change the structure and function of a wetland
 Affects humans
 Can clog irrigation systems
 Possible uses
 Provides a nectar and pollen source for bees
www.uq.edu.au/nanoworld/ images/honeybee-1.jpg
Purple Loosestrife
How can we control it?
Photo: Paula McIntyre GLIFWC
 Manual (digging, pulling, cutting)
 Not effective for large infestations
 Difficult and time consuming. Must follow up annually
when new plants appear.
 Remove as much of root system as possible and dispose of
plants properly
Chemical
Not effective for large infestations
Cutting Stalks
Credit: MJ Kewley
Org: Great Lakes Indian Fish &
Wildlife Commission (GLIFWC)
Expensive and time consuming. Must follow up with repeated applications.
Best for dry, upland areas on private property
Use an APPROVED herbicide, apply herbicides carefully. They can affect all plants, not just the
targets!
For more information on controlling purple loosestrife (and other NIS) in Ohio, visit the
Ohio Division of Natural Areas and Preserves Invasive Species web site:
http://www.ohiodnr.com/dnap/non_native/InvasiveSpecies.html
Purple Loosestrife
How can we control it?
Photo: Paula McIntyre GLIFWC
 Biological Control
 Best for severe purple loosestrife infestation (>3 acres)
 Works by using a plant’s natural enemies against it
 After 5 years of USDA testing to be sure the species would
not negatively impact wetlands and agricultural crops, three
species [imported from Germany!] were approved for use in
control of purple loosestrife:
 Hylobius transversovitta tus, a root mining weevil
 Galerucella calmariensis and Galerucella pusilla , two leaf eating
beetles
 Nanophyes marmoratus , a flower feeding weevil
 Biological control has proven successful in many areas,
BUT… caution must be used to keep the beetles
themselves in check!
http://www.ducks.ca/purple/faq/index.html - No.4
Purple Loosestrife
What can we do to help?
Photo: Paula McIntyre GLIFWC
 Report locations where purple loosestrife is found
 Ohio Department of Natural Resources Division of Natural Areas and
Preserves http://www.ohiodnr.com/dnap/
 Ohio Chapter of The Nature Conservancy www.tnc.org
 Request your local garden center or nursery to stop selling
purple loosestrife if you find it there
 Replace purple loosestrife with native plants in ornamental
gardens
 Native plants such as Cardinal flower, Blue vervain, Blueflag and Monkey
flower all thrive in the same habitat