Some plants can be real pests. They pop up where they don't belong, and instead of going away, stick around and make life miserable for all of the other plants (and animals) around them. Nonnative, invasive plants are species that come from another country-or region of our country-and spread so quickly they are difficult to get rid of. Test yourself on how well you know these plants. All of the answers can be found in Bay Naturalist, "Don't let alien invaders take over Bay's landscape," which begins on the back page.
1. True or false? All nonnative plants are threats to local ecosystems.
2. Three of these four statements are facts about nonnative invasive species. Which is the false statement?
A. Some spread aggressively by runners (a trailing stem that produces shoots) or rhizomes (horizontal, underground roots that can sprout shoots above the ground, or more roots).
B. Native predators and diseases prevent them from spreading.
C. Some grow fast and produce seeds early.
D. Some produce a lot of seeds per year.
3. How do nonnative invasive plants harm native species?
A. They grow more quickly and block out the sun before it reaches native plants.
B. Their roots grow more quickly, allowing them to take up nearby water and nutrients faster.
C. They change the balance between native plants, soil, animals and water.
D. All of the above.
4. How much does it cost the United States each year in damages, or to control, nonnative invasive animals and plants?
A. $120 billion
B. $120 million
5. What human activities are hurt by invasive nonnative species?
B. Boating & Fishing
D. All of the above
1. False (There are many nonnative plants that are important to agriculture, forestry and horticulture. They do not pose a problem until they become invasive.)