Professor Harold Spruce is one of the foremost pokemon ecologists in the country. He has a noticable tendency to get absorbed in his work to the point of excluding all other activities, but also has the habit of not quite finishing his projects. His social skills, particularly those related to staff management, are lacking to say the least.

He currently has two graduate students, Marcie and Dan, who moved with him from his old office in Rinjoh University to his new labs in Mango Village.