1They're prickly.
2Restless.
3Rambling.
4But if most plants are perfectly content to stay in one place,
5why does the tumbleweed hit the open road?
6Tumbleweeds start out as tiny seedlings.
7They sprout in late winter.
8By summer the plant takes on its round shape.
9They grow flowers nestled between thorny leaves.
10Inside each flower, a fruit with a single seed develops.
11This fruit is different than something delicious like cherries.
12Lucky for the cherry tree, a bird will carry the fruit away in its belly and disperse its seeds.
13But the tumbleweed takes matters into its own hands.
14Come fall, the plant dries out and dies.
15The seeds are still in there.
16Gusts of wind easily break the dead tumbleweed from its roots.
17See where it was attached?
18It looks kind of like bones.
19A special layer of cells at the base of the plant makes this clean break possible.
20Then the skeleton is off, shaking loose tens of thousands of seeds as it goes.
21It turns out, some living things spread their seeds better when they're dead.
22Like cowboys in a Western, tumbleweeds head out on the open range.
23But these icons of the American West actually come from the east, all the way from Ukraine.
24They're a common weed in Russia too. That's why they're called Russian thistle.
25They might have hitched a ride here in the 1800s hidden among flax seeds.
26Nowadays, they might amble onto the freeway and make you swerve.
27Or get tangled up in your irrigation system.
28They could even roll into your neighborhood, pile up and become a fire hazard.
29But a green lawn isn't what the tumbleweed is looking for.
30It can't compete with plants like grass.
31It needs a barren place like this abandoned onion field north of Los Angeles.
32With each bounce the tumbleweed sends its seeds flying.
33It spreads them out so they all get plenty of sunlight and space.
34The coiled-up embryo inside just needs a little water to sprout.
35And soon enough, this plant will strike out on its own.