SI1 REPORT: Evaluation Citizen Science ...

Kauri Rescue Citizen Science Evaluation of Kauri Dieback Treatment Tools.

March 2024

Horner I, Barton M. 2024. Kauri Rescue Citizen Science Evaluation of Kauri Dieback Treatment Tools. p 40.

ABSTRACT

Kauri dieback caused by Phytophthora agathidicida is resulting in decline and death of kauri trees throughout kaurilands. Many diseased or threatened trees are on private land, and landowners are left feeling helpless as their kauri trees decline around them.

Kauri Rescue started as a citizen science project in 2016 funded by the Biological Heritage National Science Challenge, and then became a charitable trust in 2020.

Supported by further Ngā Rākau Taketake funding, this research project built on previous efforts, involving private landowners in treating and monitoring diseased trees. It aimed to evaluate the effectiveness of phosphite treatments and the accuracy of data collected by participants.

Participants chose one of four treatment options or left trees untreated, with phosphite concentrations of 4% or 6% injected at varying intervals around the trunk. The project targeted 500 trees with reliable baseline data from the initial 3163 trees and 109 participants. Participants collected data on their trees, with professionals auditing a sample for accuracy. This research used ordinal regression to analyse how treatments affected tree health and compared data accuracy between participants and auditors.