The Once-ler
The Once-ler is the story’s antagonist. He is never pictured, other than his green arms. The Once-ler causes the deforestation of the Truffula Trees and thus the disappearance of all the creatures in the forest. It is through his voice that we hear this tale of greed. It is also the Once-ler, however, who holds the key to redemption: at the end of the book, he hands his listener the last Truffula Tree seed, in the hopes that the forest will be planted again.
The Lorax
The title character is short, brown, old and bossy. He appears out of the stump of one of the trees the Once-ler has chopped down, demanding to know what goes on here. According to the Lorax, he “speaks for the trees, for the trees have no tongues.” So, while a literal manifestation—as befitting his very precise description—the Lorax is really the voice of environmental consciousness. Some suggest he may also represent the voice of the Once-ler’s conscience. Perhaps. Something obviously starts nibbling away at that unseen part of the barely-seen capitalist.
The young boy
A young boy ventures into the far part of town to listen to the Once-ler's story. As readers, we learn next to nothing about the boy himself, other than that he is curious enough to pay the price of fifteens cents, one nail and the shell of a very, very, very old snail. At the end of the tale, he is given the last remaining Truffula Tree seeds with the caution that he if can reforest the area, the Lorax may return.
Brown Bar-ba-loots
The Bar-ba-loots are small, brown, bear-like creatures who played in the shade and feasted upon the fruits of the Truffula Trees. The deforestation by the Once-ler, however, reduces the availability of their food supply, and they are encouraged by the Lorax to leave for their own survival.
Swomee-Swans
The Swomee-Swans are another species that once freely populated the Truffula Tree forest. Upon the expansion of the Once-ler's forest, the factory's smog fills their throats and they can no longer sing. The Lorax also sends them away to find somewhere with cleaner air.
Humming Fish
The Humming Fish once inhabited the clear waters of the pond near the Once-ler's business. Once the factory began polluting their pond, however, their gills became blocked-up and they lost the ability to hum. The Lorax sends them away.
