In 2003 NZFM began a monitoring program to assess the health and vitality of important indigenous vegetation types and tree species within Lake Taupo and Rotoaira Forests. The program will also identify any significant threats to the integrity of these indigenous forest remnants so that management action can be considered. Seventeen plots were established within Rotoaira Forest in 2003, with two additional plots established in 2004 as recommended by the initial survey. A further plot was added in 2008. In Lake Taupo Forest 25 plots were established in 2004 and 2 additional plots were added in 2011 to capture frost flat vegetation. Plots are re-assessed every two years.
In 2018 Rotoaia Forest plots were assessed.
Key findings from the re-assessment in 2018 were:
- As at 2018 over 85% of crowns have intermediate health or above.
- Plot vitality remains relatively stable over the recent survey years.
- Mixed podocarp/hardwood/beech plots continue to exhibit the best vitality compared to other forest types.
- Heather and other weed species continue to have an impact in scrubland plots.
The following recommendations were made:
Heather – There are few management options for heather however should the opportunity arise for access to biological control agents through the current DOC programme, this may be of benefit.
Animal control – Hunting pressure should be encouraged where it does not conflict with forest management activities.
These plots will be reassessed in 2020, with the Lake Taupo indigenous forest plots undergoing a re-assessment this year.