The South Waikato branch covers the central North Island above lake Taupo, and includes the towns of Tirau, Putaruru and Tokoroa, the King Country, Otorohanga and the Te Kuiti area.
Founded in 1986, the branch currently has 65 members, who work on forest preservation and stream care.They also organise bush walks and meetings with guest speakers, and keep an environmental watch over the South Waikato District Council.
Meetings with guest speakers take place every two months at noon. The branch also organises bush walking in groups at Te Waotu region every three weeks.
Conservation activities include pest control, weed control and reforestation. These are carried out mainly at Jim Barnett Reserve and at the Lake Moana-Nui in Tokoroa. In 25 years, the branch has increased the bird life, improved the water quality in the region and restored the native forest.
The members of the South Waikato branch also make submissions to the district council whenever there is a concern about the conservation of the ecosystem.