Ann Otjen Hasselkus

Ann O. Hasselkus , age 88, passed away peacefully surrounded by her loved ones on April 12, 2026. Ann was born in Milwaukee, WI to Ted & Jean Otjen.

Ann is survived by her children Lynn (Galang) and Rob; grandchildren Manolo Galang (Alyssa), Nina Bushman (Maverick) & Mia Galang; along with (3) siblings (John, Lee & Bob), (1) first cousin (Katie), nieces, nephews & other family & friends.

Ann is preceded in death by her husband Bob and her parents.

Ann blazed trails as the only female class member of her University of Wisconsin Madison landscape architecture graduating class, graduated with honors & continued learning throughout her life.

After graduation from college, Ann went on to work for the Waukesha County Park System where she & her husband Bob put their stamp on designing and building Nagawaukee Park, Boat Launch, Golf Course, Wanaki Golf Course & many more locations.

After leaving the county, Ann continued her career as a self-employed landscape architect. Her note-worthy designs include: Angel’s Grace Hospice, Ice Age Trail, Oconomowoc Memorial Hospital, Oconomowoc United Methodist Church, Camp Winding River Girl Scout Camp, Bell Tower Memorial, Village Green Oconomowoc.

Ann believed in contributing to her community. She volunteered for numerous organizations including the Oconomowoc Jr Women’s Club, Girl Scouts of America, & Summit School PTO.

She was active in the Ice Age Trail development, the Olbrich Botanical Gardens & the University of Wisconsin Arboretum. She enjoyed her membership of the Woody & Hardy Plant Societies of WI and the American Society of Landscape Architecture.

Ann was an active board member for Prohealthcare Oconomowoc Hospital Foundation Board & the Village of Summit Planning Commission.

A life-long learner, Ann traveled to 6 of 7 continents including the polar region of Antartica to the mountain tops of Tibet. A list too long to imagine. She generously shared these trips with her family members & friends.

Ann enjoyed her annual reunions with her three college roommates (Mary, Betty and Sabine) & local gatherings of her 1955 Wauwatosa High School classmates.

From its inception to date, Ann demonstrated her enduring dedication to the art community through her Oconomowoc Festival of the Arts leadership.

Her life’s passion was outdoors, commitment to conservation & respectful use of our lands & environment.

A special thank you to her caregiver Svitlana & all those at ProHealthcare who supported & guided her journey.

In lieu of flowers, memorials to: the Oconomowoc Festival of the Arts, The International Crane Foundation (Sauk City, WI) or the University of Wisconsin-Madison Arboretum in Ann’s name are welcome.

A visitation will take place on April 28, 2026 at Pagenkopf Funeral Home (2228 N. Silver Maple Lane, Oconomowoc, WI 53066) from 9:30am-11:30am, followed by a service.

She loved you all.