Purple Loosestrife in Louisiana: A Call for Citizen Scientists
Join USGS in helping to prevent the spread of the invasive purple loosestrife in Louisiana.
Have you seen this plant?
Purple loosestrife is an invasive plant that can destroy marsh habitat and out-compete native vegetation. The species has invaded many wetlands in Canada and the northern United States. Though purple loosestrife has been observed in Louisiana’s estuaries, it is not yet established. Scientists at the U.S. Geological Survey (USGS) and U.S. Fish and Wildlife Service (USFWS) are working to prevent the spread of this aggressive plant species throughout the Mississippi River Delta.
What is an invasive species?
An invasive species is a plant or animal that is not native to a specific area and causes harm to the environment, economy, or human health.
Where might you see purple loosestrife?
It can be found growing in the moist soil of freshwater wet meadows, tidal and non-tidal marshes, river and stream banks, pond edges, reservoirs, and ditches. It has been observed in at least 45 states and Washington, D.C. In coastal Louisiana, purple loosestrife may be found in freshwater on mud islands in the Mississippi River Delta.
How did it reach the United States?
Though purple loosestrife is native to Europe and Asia, its seeds were accidentally brought to North America via ballast water on ships. Purple loosestrife was also intentionally introduced for use as an ornamental plant.
How does it spread?
It is estimated that a mature purple loosestrife plant can produce hundreds of thousands to more than two million seeds each year. Seeds can be dispersed in water, on wind, and by adhering to livestock, boats, and humans’ shoes and clothing.
How to identify purple loosestrife:
- Lavender-purple flowers that bloom from June to November
- Flowers have 5-7 petals
- Many flowers are grouped at the top of a long stem
- Hairy plant has narrow leaves with no teeth
- Opposite, alternate, or whorled leaves around a square stem
- Grows alone or in dense patches
- Can grow to be 1 to 9 feet tall
If you see purple loosestrife along the freshwater distributaries south of Venice, Louisiana:
- Photograph the plant, especially the purple flowers
- Record location coordinates with phone or GPS device
- Send photo and GPS coordinates to Beth Middleton at middletonb@usgs.gov or call U.S. Fish and Wildlife Service at 985-882-2000
By submitting observations of purple loosestrife in Louisiana, you will be helping the USGS, USFWS, and their partners better understand this invasive plant and help in efforts to control and predict the future spread of the species.
Join USGS in helping to prevent the spread of the invasive purple loosestrife in Louisiana.
Have you seen this plant?
Purple loosestrife is an invasive plant that can destroy marsh habitat and out-compete native vegetation. The species has invaded many wetlands in Canada and the northern United States. Though purple loosestrife has been observed in Louisiana’s estuaries, it is not yet established. Scientists at the U.S. Geological Survey (USGS) and U.S. Fish and Wildlife Service (USFWS) are working to prevent the spread of this aggressive plant species throughout the Mississippi River Delta.
What is an invasive species?
An invasive species is a plant or animal that is not native to a specific area and causes harm to the environment, economy, or human health.
Where might you see purple loosestrife?
It can be found growing in the moist soil of freshwater wet meadows, tidal and non-tidal marshes, river and stream banks, pond edges, reservoirs, and ditches. It has been observed in at least 45 states and Washington, D.C. In coastal Louisiana, purple loosestrife may be found in freshwater on mud islands in the Mississippi River Delta.
How did it reach the United States?
Though purple loosestrife is native to Europe and Asia, its seeds were accidentally brought to North America via ballast water on ships. Purple loosestrife was also intentionally introduced for use as an ornamental plant.
How does it spread?
It is estimated that a mature purple loosestrife plant can produce hundreds of thousands to more than two million seeds each year. Seeds can be dispersed in water, on wind, and by adhering to livestock, boats, and humans’ shoes and clothing.
How to identify purple loosestrife:
- Lavender-purple flowers that bloom from June to November
- Flowers have 5-7 petals
- Many flowers are grouped at the top of a long stem
- Hairy plant has narrow leaves with no teeth
- Opposite, alternate, or whorled leaves around a square stem
- Grows alone or in dense patches
- Can grow to be 1 to 9 feet tall
If you see purple loosestrife along the freshwater distributaries south of Venice, Louisiana:
- Photograph the plant, especially the purple flowers
- Record location coordinates with phone or GPS device
- Send photo and GPS coordinates to Beth Middleton at middletonb@usgs.gov or call U.S. Fish and Wildlife Service at 985-882-2000
By submitting observations of purple loosestrife in Louisiana, you will be helping the USGS, USFWS, and their partners better understand this invasive plant and help in efforts to control and predict the future spread of the species.