“But those trees! Those trees! Those Truffula Trees! All my life I'd been searching for trees such as these.”
The Truffula Trees provoke the greed of the Once-ler. This is a pivotal moment, where the Once-ler views the Trees for the first time, and immediately covets them. After this, for the Once-ler, there is no going back.
“I speak for the trees, for the trees have no tongues.”
This famous line demonstrates the impetus of environmentalists everywhere. The Lorax must be the advocate for nature as they cannot advocate for themselves.
"... UNLESS someone like you cares a whole awful lot, nothing is going to get better. It's not."
This line summarizes the final moral lesson of the story: changing the status quo is up to the next generation, and it will require somebody's direct intervention. That choice—whether or not to intervene—is a crucial one, because the stakes of the environment rest on it.
