She progressed to the role of assistant youth division manager before becoming an area committee member and an events officer.
Continuing a family tradition, her eldest son is now a cadet and her other son is about to join the charitable organisation.
Ms Trass teaches 40 cadets in Masterton helping them develop not just first aid skills but leadership and life skills.
"I love teaching the kids, lots of cadets become nurses and paramedics, it's great to see how they go afterwards."
She said one of her best memories is of being a cadet and going to St John competitions in Napier where they practiced first aid skills in the field.
She was also honoured to go to Government House when she was 18 to receive a Grand Prior Award from the Governor-General.
Being a volunteer had enriched her life in more ways than one, she said.
"Some of the people I met years ago are still my friends."
Another Wairarapa woman, Catherine Brazendale, has also been selected as a Member.
She joined St John when she was 11 in South Wairarapa.
Throughout her time, she was a youth member, ambulance officer, events officer and an area committee member.
The pair will officially invested as Members at investiture ceremonies next year in Auckland.
Every year Membership of the Order is given for dedicated service to St John.
The Order traces its origins back 900 years and is an independent part of the NZ Royal Honours System.