Watch Out For The Spongy Moth

This nasty little moth is once again starting to flourish in New Zealand. The spongy moth is a pest and needs to be eradicated. If you see a weird fluffy type nest with tiny little caterpillars please take a picture and notify MPI.

Spongy moths only live for a short time, around a week, however they lay hundreds of eggs in a single mass. The egg masses then hatch, releasing hundreds of hungry caterpillars. These caterpillars can strip the leaves from entire trees, devastating stands of trees, and produce hundreds more moths.

The spongy moth mostly lives in Europe, Russia, China, Korea, and Japan. It turns up in all sorts of places, like the western coast of North America. Although it has been eradicated in many places, it has established on the east coast of North America.

In 2003, MPI found the moth in Hamilton. It was declared eradicated in 2005. There is a surveillance network monitoring for this moth near our borders.

Why this is a problem for New Zealand

The caterpillars have a broad host range. We know the caterpillar feeds on many tree species that are common in our towns and cities, such as oak, fruiting trees, and birch.

In large numbers, the caterpillars are a public nuisance. They leave large amounts of droppings and have tiny stinging hairs that cause an itchy or painful rash.

We don’t know what impact this caterpillar could have on New Zealand forests. Some native trees belong to the same groups as trees that are affected overseas. Some forms of spongy moth even have a taste for pine trees.