Zebra Mussels are very small, usually no bigger than this body part.
What is a fingernail?
Spongy Moth caterpillars eat large amounts of these, which weakens trees and makes them vulnerable to disease.
What are leaves?
The amount of natural predators for the Purple Loosestrife in Colorado.
What is zero?
This country is where the Yellow Starthistle originally came from?
What is Spain?
This word describes a plant or animal that does not belong in an area.
What is non-native?
Zebra mussels harm native mussels by doing this.
What is cutting their shells?
This is the region that Spongy Moths are most widespread.
What is the Northwestern United States?
The Purple loosestrife grows rapidly because it produces this many seeds per plant per year.
What is hundreds of thousands (up to 3 million)?
The Yellow Starthistle spreads rapidly because it produces this amount of seeds per plant per year.
What is tens of thousands?
This group is the biggest contributor to the spread of invasive species?
Who are humans?
Zebra Mussels originally came from this sea in Russia.
What is the Caspian Sea?
Trouvelot intended to breed spongy moths with these insects.
What are silk moths?
The Purple Loosestrife uses its thick and long roots to clog this thing that other things depend on.
What are waterways?
The flowers of Yellow Starthistle are surrounded by these sharp, stiff structures that can grow up to ¾ of an inch long.
What are spines?
One reason invasive species grow so quickly is because they don’t have these in their new environment.
What are natural predators?
This is what zebra mussels look like, giving them their name.
What is brownish-tan with stripes?
The century that Spongy Moths arrived North America
What is the 19th century (1800s)
Purple loosestrife was originally brought to North America for this purpose.
What is ornamental gardening?
This animal is especially at risk because eating Yellow Starthistle can be deadly.
What are horses?
An invasive species is one that is non-native AND does this.
What is causes harm to the environment, economy, or human health?
Zebra Mussels were most likely carried to the United States by this method in the 19th century.
What is ballast water from ships?
This feature of Spongy Moths' caterpillars cause skin irritation in humans.
What are hairy bodies?
This type of insect has been used as a biological control for purple loosestrife.
What are leaf-eating beetles?
Yellow Starthistle was likely introduced to North America in 1869 when these contaminated seeds from Chile brought the plant.
What are alfalfa seeds?