One of the things that hippies like to do is live in trees. They want to get away from the "Man" so they climb up trees and make these shelters, where they live.
|shake the hippie out of the tree|
French police are trying to shake the hippies out of the trees because they're making a mess. When the hippies are gone the French will build an airport and the forest will be gone, as will the hippies.
I like the last part of that equation.
Here in Texas we're working pretty hard to transport the hippies out of Austin and into California. San Francisco, to be precise, where they belong.