to give air that we breath in and keep in carbon dioxide
A landscaper can plant trees, but trees are better off with an arborist.
Lumberjacks
Landscaping is a job choice, not a nut. So no, landscapers do not grow on trees.
Gardener.
His job is to shake trees....
They grow wool on wool trees.
To strip the leaves, bark, and branches of trees with its trunk.
for furniture
the emergant layer shields all the trees from the sun
A botanist studies trees and plants. Some of their job is in the lab and some of their job is in the field which can be forests and meadows.
Arborist.
It's actually everybody's job to protect what trees we have left. People who actively protect trees are called forest defenders, or more specifically, tree sitters. More than individual trees, we have to be considerate of complete ecosystems and migration corridors. Certain animals require old growth trees to live. The marbled murrelet needs the wide braches of ancient trees to stand on as they have webbed feet. The red tree vole, also endangered, lives in old growth redwood and Douglas fir forest.