At the outbreak of WW2 Merle Farland was nursing on Vella Lavella as part of the Methodist Overseas Mission. In late 1942 she returned to New Zealand and in 1943 joined the New Zealand Army Nursing Service (NZANS) being appointed as a Sister, NZANS, at Trentham, on 27.4.1943. She subsequently served at 4NZGH New Caledonia and on Guadalcanal, Solomon Islands. She also made one trip on HS Maunganui to the Middle East and on 18.12.1945 was promoted to become a Charge Sister.

After the war Merle Farland went on to complete Post-Graduate training in New Zealand and became Principal of the Nursing School at Lautoka, Fiji, and then on to the UK where she undertook specialist training before taking up work for the Colombo Plan and the World Health organisation in various war-torn countries around the world before retiring back to Auckland in 1967