Leif John Youngdahl, 72, of Marshall, IL and formerly of Marshall, MO passed away Saturday morning, August 28, 2021, at home with his loving family. Leif was born in Wilmington, IL on August 25, 1949 to Charles and Celia (Waring) Youngdahl. He was an only child, raised in Joliet, IL. He married Alta Bartram on June 8, 1974 at Marshall Baptist Church in Marshall, IL. He was preceded in death by his parents and his in-laws Pete and Clara (Cornwell) Bartram. Leif is survived by his wife, Alta; daughters, Erika Dawn Youngdahl and Carla Youngdahl; and granddaughters Evelyn Bauman and Greta Berg; sever brother- and sister-in-laws, nieces and nephews. Leif received his bachelor’s and master’s degree from Eastern Illinois University where he met Alta. He earned his Ph.D. in Plant Science in 1975 from the University of Delaware. In his life he had two careers – agriculture research and college teaching, with each leading to its own opportunities travelling with his family. He began postdoctoral work and an assistant professorship in the agronomy department at Purdue University. Through these positions he worked in Brazil, South American at Brazil’s National Corn and Sorghum Research Center as part of an agricultural development project. He then spent 12 years working for the International Fertilizer Development Center in Muscle Shaols, AL. During this, Leif lived with his family for 1 ½ years living in Cali, Colombia, South America, while collaborating with the International Center for Tropical Agriculture. He began his teaching career with a 1-year position at Olney Central College in Olney, IL teaching biology. In 1991 he started at Missouri Valley College in Marshall, MO teaching a variety of science courses. In 1998 he was appointed to be Dean of the Math-Science Division. He was a member of the Marshall First United Methodist Church and sang in the choir. While living in Marshall, MO he served on the Marshall Public Library Board of Trustees and was a founding member of the Marshall Public Library Foundation. While his work lead him and his family across the country and across the world, he also enjoyed many opportunities to travel for fun. They regularly took long summer vacations. He enjoyed boating, fishing, and fixing small engines. Leif’s family is thankful for the care from Haven Hospice, especially Tiffani and Courtney, They also would like to thank Linda, Morgan, Jenny, neighbors, and church family for their love and support. A memorial service will be held at the First United Methodist Church in Marshall, IL on Saturday, September 4, 2021 at 2:00 PM. Since Leif lived with Parkinson’s disease for over 30 years, in Lieu of flowers, the family requests donations to the Michael J. Fox Foundation for Parkinson’s research. Online condolences are being accepted at pearcefuneralservices.com.