A University of Hawaii diagnostician stumbled upon an unfamiliar rust on a mamaki leaf in August 2013. The culprit was promptly identified as Pucciniastrum boehmeriae. Additional surveys in nurseries and botanical gardens throughout the Hawaiian Islands failed to detect more occurrences of the rust, although it was detected on Akolea plants on Oahu in 2016.
Chinese Rose Beetle
These holes appear in otherwise beautiful mamaki leaves with no apparent caterpillar, moth, or aphid to be seen. Culprit: Chinese Rose Beetles
This issue seems to appear as part of the dying process in older (roughly 10 years) mamaki plants that have been abused. Over-pruning, lack of water, too much sun, and poor soil health are just a few of the potential culprits for this slow die-off. The bug probably has a more generic name, but we have we have dubbed it “mamaki bore” until further analysis is done at University or Hawaii.