In the 1970s many college students or college graduates planted trees in the summers to make money for school or just to live

 The idea was a lot then that since so many trees were being cut in places like Oregon and even parts of California that people wanted to replace these trees somehow so new ones would replace eventually the ones that were cut. also, where I live on the coast there was a bad fire in the pine forests near San Francisco on the coast and people planted trees throughout this fire area too eventually so now the trees planted in the early 1980s are quite large now as you can imagine in this once burned off area of the Coast of California. I remember I was watching "Raiders of the Lost Ark" at a theater and we saw fire about 30 to 50 feet high along a ridge near us. We were safe but many people lost their homes in this fire. Then later people came and planted trees which prevents erosion from being as bad as it can be after a fire especially during heavy rains in the Winters along the coast.

Also, many of my friends planted trees or worked as Firemen for the Forest Service or even the California Department of Forestry then in the 1970s too. One friend was in a fire and a boulder came down a hill and one friend screamed "Steve! Watch out" So, Steve was wearing a hard hat or he would have died that day and put his hand on top of the hard hat and took the blow on top of his hard hat and hand. His hand broke and the boulder knocked him out so he was in the hospital a few days after this recovering and couldn't fight fires the rest of the summer but at least he survived.

So, many of the people who planted Trees also worked sometimes for the Forest Service Fighting Fires then in the  late 1970s too.

Note: As things burn down often rocks and trees and boulders come loose and  can be very dangerous and sometimes fatal to Firefighters during fires especially on steep hills when fighting fires in the wilderness.