Joanne Isaak, formerly of Clark, passed away in Idaho. A time of visitation will be held on Sunday, October 26, 2025, at Furness Funeral Home from 9am until 12pm. Following visitation, family will travel to Kulm, North Dakota where burial will take place at the Seventh Day Adventist Kulm Cemetery.
Joanne Isaak, a cherished member of the Clark community, passed away on October 8, 2025, at the age of 85 following a courageous battle with an aggressive form of Parkinson's Disease. She had been diagnosed in December 2024.
Born on February 4, 1940, in Waverly, N.Y., Joanne was the youngest of five children born to Judson and Marian Spencer. She spent her formative years on a dairy farm in Owego, N.Y., where she developed a deep appreciation for nature, animals and hard work.
Joanne graduated from Union Springs Academy in 1957 and went on to attend Atlantic Union College in South Lancaster, Mass. It was there where she met the love of her life, DeLane Isaak. The two were married in Owego on August 14, 1960, and together they built a life centered around education, family and faith.
As dedicated teachers, Joanne and DeLane raised their three children—Gregory (born 1962), Mary (1963) and Geoffrey (1965)—while living in several states, including North Dakota, Ohio, Tennessee, Massachusetts and Pennsylvania. In 1984, they settled in Clark, where they remained active in the community. DeLane retired from teaching in 2000 and passed away in June 2016.
Joanne was a woman of many passions. She found joy in gardening, playing the French horn and caring for a lively menagerie of pets—dogs, cats, chickens, ducks and geese. A gifted artist and exceptional cook, she brought creativity and warmth to everything she touched. Her intellectual curiosity was boundless; she was deeply read in suject ranging from history and horticulture to cryptology and Biblical archeology. A devoted student of scripture, Joanne was studying Hebrew until the final months of her life.
She was preceded in death by her parents, all four of her siblings and her beloved granddaughter, Megan Alyssa Leader.Joanne is survived by her children: Greg (Gabbrey) Isaak, Mary (Regan) Leader and Geoffrey (Vikki) Isaak; her grandchildren: William Leader, Benjamin (Autumn) Leader, Aubrey Isaak and Asher Isaak; and her great-grandchildren: Atticus and Ansel Leader. She also leaves behind a large extended family of nieces and nephews who will miss her dearly.
To plant trees in memory, please visit the Sympathy Store.
402 N Commercial St, Clark, SD 57225

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