Invasive Species Investigation
Invasive Species Investigation
Lesson Summary: In this two part lesson, students will learn the difference between native and non-native (introduced) plants, as well as what it means to be an invasive plant. Students will learn why invasive plants are problematic and how they are able to take over an ecosystem and oftentimes form monocultures. In the first half of the lesson, students will take part in an E2T2 activity that will enable them to identify and gain knowledge about plants (both native and non-native) in their schoolyard. In the second half, students will conduct a field investigation to determine the relationship between the distance from human-made walkways (i.e. concrete) or buildings and percent cover of invasive species. After data collection and conclusion, students will then brainstorm ways in which they can improve their schoolyard habitat for native plants and animals. Lesson extensions could evolve into a service learning project.
After this lesson, students will be able to:
- Compare and contrast native versus invasive plants.
- Identify and describe at least one native or invasive plant in their schoolyard.
- Identify and model the steps of a scientific process.
- Determine the average percent cover of invasive plants in different areas of their schoolyard relative to human-made walkways or buildings.
- Analyze data and make a conclusion from their data.
- Brainstorm ways to improve their schoolyard habitat.
- E1T1 cards
- IslandWood Journals
- Butcher paper
- Measuring tape
- 3 Hula hoops (sectioned off into 4 sections)
- Data collection sheets, clipboard, & pencils (one for each student)
Time: 2.5 hours, or two 1 hour sessions.
Introduction: In the Classroom (20-30 minutes)
Can anyone tell me what does it mean to be native to something? To come from that particular area. So what does it mean to be non-native? To not come from a particular area. So when you were at IslandWood, you learned about some native plants of Washington, or plants that come from Washington and grow naturally in Washington’s climate & soil conditions. Can anyone think of an example of a native plant from Washington that you learned about at IslandWood? Gather a list on the board of these plants.
In addition to native plants, we also have non-native plants, sometimes called introduced or exotic plants of Washington. These are types of plants that are living outside of their native range and have somehow arrived in Washington. Can anyone think of how or why a plant might have arrived in Washington from a different state, or even a different country? Gather a list of reasons on the board (reasons could include: intentional- ornamentals, cultural nostalgia as a result of immigration, food, economic gain, biological control, preservation & avoid extinction, erosion control; and accidental- transportation by human vectors). Most non-native plants have been intentionally introduced. A non-native species that colonizes a new area may gain an ecological edge since the insects, diseases, and foraging animals that naturally keep its growth in check in its native range are not present in its new habitat.
Sometimes introduced or non-native species can become invasive. What do you think it means to be invasive or an invader? Invasive plants have a tendency to spread, and invade or take over the habitats of other native plants. When this happens, invasive plants can form mono-cultures or places where one species is dominant. Oftentimes, invasive plants have adaptions to help them do so- such as thorns, tendrils, fast growth, rapid reproduction rates, high dispersal ability, tolerance of a wide range of soil & weather conditions (generalists), and no natural predators (insects & animals) and diseases that affect them. For example, if you were a deer and you came across two fine looking bushes, and one bush had berries you had tried and enjoyed before and the other had berries you had never tried before and didn’t know if they were poisonous or not, which one would you eat?!
In order to investigate the plants in your schoolyard, we’re going to first learn about the different types of plants that are present by doing an E1T1 activity. I’ll remind you of how this works once we get outside.
Secondly, we’ll investigate the percent cover of invasive plants in your schoolyard. Please flip to a blank investigation page in your IslandWood journal (pg. 10 or 12 or create your own investigation worksheet beforehand). The question for investigation today is: What is the relationship between percent cover of invasive species and distance from sidewalk/ building/ concrete? Please fill this question out in your journal. In this question, what is the measured variable? And what is a measured variable? The measured variable is the value that is determined or measured, in this case the percent cover of invasive plants in a particular area. What is the changed variable? And what is the changed variable? The changed variable is part that we change or alter as scientists; in this case it is the distance from the sidewalk/ building/ concrete.
Percent cover is the area of ground that is covered by invasive species. For this investigation, we’ll use a hula hoop that is split into 4 sections, or 4 quarters (or 8 sections to make it more difficult) to help us determine percent cover. Show students the hula hoop and how you divided it. So, if most of 2 sections were filled with invasive species, how much of the percent cover would be invasive species? About 50% or ½.
Before students head outside, make sure all students are wearing proper gear & each have a clipboard with IW journal attached, as well as a pencil. Be sure to grab hula hoops & measuring tape.
The core of the lesson:
E2T2: Briefly remind student how E1T1 works, and explain that instead of teaching by yourself, you’ll be partner teaching with someone else. Explain that each person within the pair should be sharing equally (they can either switch off from group to group or equally share each time). Allow for at least 2 minutes between each pair, and remind students to try to make their lesson interesting, using visuals, hands-on approaches, etc. If they come across another group who is still teaching students, stand a few steps away until they have moved on.
While students are waiting for their turn, have them use a big sheet a butcher paper to brainstorm a procedure for their investigation with their teacher. (If the group is big and you have 2 extra adults, you can subdivide them into 2 groups for brainstorming.) Encourage them to get concrete steps written down on the paper.
As students finish E2T2, first have them check over the procedure to see if they have anything to add. Secondly, have crayons & journals ready. Ask students to rub their leaf into a blank page in their journal (pg. 11 or 13 if they’re blank) and write 1-2 facts about their plant. If they have time, they can do another group’s plant as well.
Investigation: Review the procedure developed by the students as a large group and make sure students didn’t leave anything out. Hopefully it looks something like this:
- Split into 3 groups, which will represent 3 trials for a fair test.
- Measure the first distance from the sidewalk/ concrete/ building and randomly place the hula hoop in that designated distance.
- Estimate the percent cover of invasive species that are within the whole hula hoop. (Before breaking into smaller groups, do a couple examples with students to make sure they understand the fractions.)
- Record the data in the data chart. Repeat steps 2 & 3 for each distance.
- Combine the data with the whole class. Find the average for each distance.
- Make a conclusion from the data collected. Speculate where invasive species removal should happen first.
After reviewing the procedure, ask students (& teachers!) if they have any questions. Then, ask students to make a prediction, which distance do they expect to find the greatest percentage of invasive species? Have student stand up/ sit down to represent this. Using the procedure that the group created with their teacher, begin the investigation! Make sure that each student has a chance to do each step within the group (it may be helpful to assign different jobs to students for each data collection).
Optional art connection: Give students take 3-5 minutes to draw a giant circle and then sketch the inside of the hula hoop. Then, students can identify the species that are present within this circle after each data collection using the E1T1 cards. Students can use blank pages in their journal for this (pg. 3, 11, 13, 15, 17, 19, 29, 30, 31, 37, 38).
Conclusion: Gather students back together (either inside or out depending on their energy and attention level) to make a conclusion. First, pool all the data together using another big piece of butcher paper or the board. Then, together or individually, ask students to calculate the average and write a conclusion. Remind the students that a conclusion should answer the investigation question and include both the highest average and lowest average.
After sharing a conclusion, ask students to brainstorm next steps. How can we make this schoolyard habitat more habitable for native plants and animals? Why is it important to remove invasive plants? How did the invasive plants get in our schoolyard in the first place? How do we make sure that once invasive plants are removed that they do not come back?
Have each team or group share to the class their proposed steps for action!