Mack Willis spent the majority of his life as part of a weed control spot-firing team. With nature seemingly going out of control, he was happy to do his duty. Killing encroaching kudzu became his ultimate joy in life and he did his job to the letter. While many others bemoaned their station in life, Mack remained one of Thayer's most valued weeders for over two decades.
In his later years, leading a spot-firing team became too laborious for his old bones. After noticeably losing a bit of spring in his step, his supervisor had the good heart to recommend him for a job he was much better suited for: the much sought-after position of algae pond manager.
Mack's primary tasks during this time were adjusting pond depth to maximize the thrive rate of the algae, heating or cooling the ponds to promote maximum oxygen production, chasing off the panthers that had taken a strong liking to the flavor of the algae, and, of course, managing encroaching vegetation.