The following report has been received from Auckland Council’s Arboriculture and Landscape Advisor, Mr. Simon Cook:
“We have found an infestation of the disease in elms on the maunga (Mt Hobson) – very sad. The trees are situated on the eastern side (Remuera Rd side) of the maunga and are in two groups totalling around 25 trees. We have had an infected Elm Bark Beetle (Scolytus multistriatus) trapped nearby one of the newly infected trees’.
Samples (from suspect trees) have been sent to Scion in Rotorua for analysis, results will almost certainly be positive for the disease (symptoms are almost certainly DED) . What this means is that all 25 10-20m tall specimens will require removal, leaving quite a gap in the vegetation on this highly visible section of our landscape. All material will be chipped and will remain on site, the exact methodology is yet to be determined but I will certainly forward this and dates etc once confirmed. The Biosecurity Act 1993 does not allow this ‘unwanted organism’ to remain alive and we certainly want to protect some of the other fantastic elms in the area”
The tree removal has been authorised
Dutch elm disease is usually spread by the bark beetle carrying fungal spores. It spreads quickly and is nearly always fatal. Infected trees often harbour bark beetles and must be buried, mulched or burnt.
Mr Cook urged elm owners to check their trees. New cases become evident during spring, with elm either not coming into leaf or wilting rapidly after bud burst.”
Dutch elm disease is thought to come from Asia, but is so-named because it was discovered in the Netherlands.