SpongeBob SquarePants Season 13 Episode 15 Arbor Day Disarray / Ain't That the Tooth Episode Title: Arbor Day Disarray / Ain't That the Tooth Episode Description: Arbor Day Disarray:Sandy creates special acorns using science to create "saltwater trees," which are trees that can grow underwater, with various Bikini Bottomites like Patrick, Squidward, Mr. Krabs and Mrs. Puff getting theirs. Eventually, the trees start talking and making rude, "salty" remarks and eventually run loose around Bikini Bottom. Ain't That the Tooth:Patrick confuses returning burglar antagonist Dorsal Dan for the Tooth Fairy, and he and SpongeBob are tricked into following him around as his goons, attempting to steal money and riches from the innocent. However, the duo's naïveté ends up ruining Dan's plan, often causing more misery and abuse for him than intended.