The Tumbleweed is a plant that breaks away from its roots and is driven around by the wind. These plants can be as small as a soccer ball or as big as a car. They grow and spread very quickly because the hot, flat desert terrain makes it easy for them to travel.
The Tumbleweed disperses, or scatters its seeds as it rolls around the desert. These seeds are unusual because they have no protective coating.
In warm weather they grow quickly into a thorny flowering plant. This plant then breaks off from its root and spreads its own new seeds.