Mr. Douglas runs an apple orchard and showed up in The Whistle Stop (Episode 130). He's mostly notable for accepting help from Arielle, who used her Ledyba to pollinate his apple trees—a pretty straightforward partnership that worked well for his operation.
When Ash's group visited the orchard alongside Arielle, Douglas made a quick appearance, driving past on his tractor to say hello to her before heading off. It's a minor role, though the episode captures the kind of practical Pokémon-human cooperation that defines a lot of the series. Interestingly, the Japanese version didn't bother naming him at all.
Content compiled by AnimeList.moe from publicly available sources.
