Mission: Purple loosestrife

Research Question

How is purple loosestrife affecting biodiversity in Maine?


You're invited

Invasive species are the second biggest threat to biodiversity worldwide. Scientists in Maine are tracking specific invasive species like purple loosestrife to see if they are having an impact on biodiversity in our native wetlands, fields, forest edges, and drainage ditches. Help add to this important dataset by looking for purple loosestrife populations AND reporting the number of different species you find living nearby. Your data will help scientists see if this invasive plant is affecting biodiversity in Maine in the short and long term.


Mission steps

1. Print the Species ID card for purple loosestrife

2. Print an Upland Species & Habitat Survey datasheet

3. Go out and look for purple loosestrife!

4. In areas where you FIND purple loosestrife, use a 1 meter square quadrat to count the number of different species you find nearest to the loosestrife

5. Put your biodiversity count in the "Species diversity" field on the last page of your datasheet

6. Go to your My Vital Signs page (link at top right) to add your species observation and biodiversity count

Why this Mission matters

Definition of biodiversity:
The many different species of living things found within a defined geographic region

A healthy ecosystem doesn’t just have a lot of organisms, it has a lot of different organisms. Biodiversity is one of the best signs that an ecosystem is healthy, productive, resilient, and able to sustain itself naturally over time. Diverse ecosystems are important to Maine and to the health of the planet. Biodiversity provides natural services, resources, and cultural benefits.

    Services include: Protecting water resources and soil, storing nutrients, recycling, breaking down and absorbing pollution, stabilizing the climate, preventing and recovering from natural and human disturbance

    Resources include: Food, medicine, products

    Cultural benefits include: Research, education, recreation, tourism, a source of values and tradition

The two biggest threats to biodiversity worldwide are habitat loss and invasive species. In Maine plants and animals lose their habitat and the resources they need to survive primarily through urban development. Invasive species are a growing threat to biodiversity in Maine. Without predators to keep their populations in balance, invasive species are able to out-compete native species for food, shelter, and space. The introduction of an invasive species like purple loosestrife may increase biodiversity in an area in the short term, but biodiversity often rapidly declines once this new species establishes and expands its population.

Want to know and do more?

Beetles used to fight invasive plant in Maine
Rachel Carson National Wildlife Refuge Uses Galerucella Beetles to Control Purple Loosestrife in Maine

Vital Signs Mystery graph activity
Use a mystery graph to kick off your study of purple loosestrife and Galerucella beetles

York County SWCD
Resources from York County Soil & Water Conservation District. York county has been hardest hit by purple loosestrife.


That's a good question - I think that the central mission question: "is purple loosestrife impacting biodiversity in Maine?" is only important because biodiversity is important.

So, when I reed about the "Why this mission Matters," it is a general reason. I was looking for specifics. I know that my local garden club was joining in taming this invasive plant but do not really understand why. Also, I inadvertently planted White Loostrife and want to know if it was right or should I have controlled it.

Hi Jradigan,

That's a good question - I think that the central mission question: "is purple loosestrife impacting biodiversity in Maine?" is only important because biodiversity is important. In other regions purple loosestrife has had large negative impacts on biodiversity, but we're not sure to what extent the same is true here. Until we have more data to answer the question of this mission, the "why it matters" will remain vague. Does that make sense?

In answer to your question about white loosestrife, the Maine Natural Areas program would be a great resource. They're quite helpful and deeply knowledgeable about such things. That said, prudence would suggest being careful with all relatives of purple loosestrife!

I hope that helps,

Here's an example of a local effort to control loosestrife that might be of interest.


I would like to take my students on an architectural tour of our city and would want them to be good observers of the different geometric shapes used. They would be asked to document specific shapes and determine the frequency of occurrence. We could use the data to discuss the shapes and describe their properties and why they were used.