Daughter of Bill and Thora Trigg, Wendy was born into a farming family. Her father and his family had taken up land at Cummins which was at the time considered too wet to farm, and were struggling to make a go of it. Wendy attended Cummins Area School for Years 1-7, and then, funded by her grandfather's WWI war savings went to Methodist Ladies' College 1952-4. She left school at the age of 15 and a half, and helped her father at home, working part-time at the local chemist's and later the doctor's surgery.
She married a farmer, Brian Treloar, when she was 21, and they had three sons, all of whom wanted to return to the land after their schooling. Wendy has worked with her husband on the farm, in what she describes as "a solid partnership for all this time and this has been a source of great writing material...The farming occupation leads lots of us up the writing path, as there are so many things to record!" She and her husband have been very much involved in the local community, as were her parents before her. During the late 1980s she was a monthly correspondent for the Cleve, then Farmers' Federation magazines, Rural News and local Cummins correspondent to the Port Lincoln Times. She is a member of the Cummins Writers, a group which began typing and photocopying collections of their writings in 1986 under the encouragement of Petrea Brooke from the Pt Lincoln College of TAFE, and has gone on to produce published anthologies of regional writings.
In 1990 the School Librarian asked local writers Wendy Treloar, Sylvia Laube and Ivy Edwards to write stories for the school children. They then selected some of them, had the children illustrate them, and kept them in the school library as "Tales from Earth and Beyond". Wendy wrote "One Man's Story" (illustrated by student Jeffrey Krieg), "The Tractor" (illustrated by Kirsty Laube), "Trouble on the Farm", "A Rabbit or What?", "Fire", "Shut the Gate - Please", "Trouble", and "Bogged".
As well as her creative writing Wendy is concerned to record the history of the region. She was a co-compiler of Cummins, Its People and History (1988) and a book to commemorate the anniversary of the Cummins Bowling Club (1993). She contributed to Eyre Remembers (1995).
