Environment

Gorse Seed Weevil. Biocontrol agent:
Gorse Seed Weevil

Scientific name:
Exapion ulicis

Target weed:
Gorse
Ulex europaeus

What do gorse seed weevils look like?

Adult weevils are 1.8mm to 2.5 mm long, grey and pear shaped with the typical weevil snout.

How do I find them?

The adults are found all year around on gorse plants. They feed on the developing seeds within the pods and pupate in white pupal cells inside the pods. The newly emerged adults can be seen inside mature pods and can’t escape until the pods burst open.

What about their life cycle?

There is one generation per year. The tiny yellow eggs are laid in batches inside green pods in spring. The larvae (grubs) are white and legless with brown heads and reach a maximum size of 2.5mm.

Where are they established?

These weevils are widespread throughout Northland.

When and how can they be harvested for redistribution?

Adults are easiest to find on gorse in spring and early summer or as newly emerged adults inside mature pods. Beat bushes over a white sheet to collect weevils for redistribution. Avoid activities that will interfere with any part of their life cycle, and if undertaking other gorse control measures over a large area, leave a few bushes nearby as a reservoir for the weevils.