Obituary published on Legacy.com by Osthus Funeral Home - De Smet on Mar. 8, 2026.
It is with deep sorrow that we announce that Arlen Wallum passed away on March 2, 2026, in Sioux Falls, SD. He lived a life defined by his kindheartedness and devotion to his family, friends, and community in
De Smet, SD.
Public Visitation will be held from 5:00-8:00 PM on Friday, March 20, 2026, at Crawford-Osthus Funeral Chapel in
De Smet, SD, with Memory Sharing from 7:00-8:00 PM.
Private Funeral Services will be held with a recording of the service posted to his obituary page on www.crawfordosthus.com for the public. A Celebration of Life for friends and family is planned for Summer 2026 at Wallum Farms in
De Smet, SD (date pending).
Private Burial at De Smet Cemetery in
De Smet, SD.
The family requests donations made in Arlen's memory to Watertown Humane Society or Sioux Empire PitRescue in lieu of flowers. In person donations to a South Dakota State Memorial Fund in Arlen's name can be made at the March 20th Visitation, Summer 2026 Celebration of Life or mailed to the funeral home at PO BOX 115 in
De Smet, SD. For any help or questions about donations, contact
[email protected].
You can also donate online to: The Watertown Humane Society https://watertownpaws.org/give and The Sioux Empire PitRescue: https://www.pitrescue.org/donate
Arlen was born on January 28, 1949, in
Huron, SD, to Juanita and Milo Wallum. He spent his childhood side by side with his twin brother, Arden, and grew up alongside his younger sister, Veda, and brother, Curt. When he wasn't working on Wallum Farms, you could find him carting around the family ponies, Lightning and Bubblegum, for friends to ride. He loved the adventure of family trips to Lake Poinsett for boating, as well as relaxed nights sitting around the dining table chatting with close friends and family. Arlen later became an avid athlete, playing on the De Smet High School basketball and football teams. He ultimately earned an all-state championship title and a full scholarship to play college football.
Arlen earned a bachelor's degree in Agricultural Economics from South Dakota State University, where he found a group of lifelong friends who remained a strong source of support. He then returned to De Smet, helping his father create Wallum Farms, Inc. During this time, he continued to be an active member of the De Smet community, proud to be a Mason and accomplished in the martial arts. He developed a passion for mountain sports, taking countless backpacking and ski trips in Colorado. Eventually, he went on to build a long career with the USPS, serving as a rural mail carrier known to go out of his way for the people of Kingsbury County.
Arlen's kindness, generosity, and love took many forms. During his later years in De Smet, he helped make Wallum Farms a haven. Every summer, he made sure his nieces and nephews always had the best fireworks for the Fourth of July and helped Arden fix up the 1970 Land Cruiser for the family to ride around town. His extensive collections of albums and films were always offered up for the family to enjoy. As a self-taught electronics enthusiast, he became the family expert on high-quality AV. He was fiercely proud of all his nieces and nephews, always sharing stories about them and taking every opportunity to affirm them and support their accomplishments, no matter how big or small. Arlen never missed AJ and Brad's sporting events in SD, befriending the other parents and serving as the absolute best cheerleader.
Beyond De Smet, Arlen spent his time visiting family across South Dakota, Minnesota, and California, celebrating countless holidays and birthdays, and welcoming grandnieces and grandnephews into the world. You could often find him cheering on the Jackrabbits with Veda, Randy, and Marsha, who shared his love for SDSU basketball and football. In his later years, he cherished peaceful sunsets and cloud-gazing with Marsha and their dog Tucker, with whom he shared the final chapter of his life.
Arlen will be dearly missed and lovingly remembered by his siblings Arden, Curt, and Veda, and their spouses Tina, Mary, and Randy; his many nieces and nephews, AJ, Paul, Brad, Anna, Michael, Emily, Alison, Manuel, Yana, James, Libby, and Sam; his grandnieces and grandnephews; and his companion, Marsha, and her children, Dan and Christy.
Arrangements entrusted to Crawford-Osthus Funeral Chapel www.crawfordosthus.com
To send flowers to the family or plant a tree in memory of Arlen Wallum, please visit our floral store.