Red clover casebearer moth
The red clover casebearer moth has been found in Auckland and mid-Canterbury. This moth is a pest of red clover with its larvae feeding on developing seeds inside the plant's flowers.
In late 2016, the red clover casebearer moth (Coleophora deauratella) was found at several locations across Auckland. In early 2017, the insect was also found in a red clover crop in mid-Canterbury. Indications are that the moth has been in New Zealand for some time – since at least spring 2015.
The moth is native to Europe and Asia Minor and has been present in North America since the 1960s.
Risk to New Zealand
The moth has been recorded as a serious pest of clover seed production in Canada. The most significant risk is to New Zealand's clover seed production industry from larvae damaging seeds.
However, its potential effects are uncertain. There are 2 similar casebearer moth species already in New Zealand and these are successfully controlled in crops by biological and chemical methods.
What's being done?
MPI is working with the Foundation for Arable Research and farming industry groups to inform farmers about the control measures available to them. There are good options available.
MPI is not trying to eradicate the moth because:
- it's potentially widespread here and the red clover it feeds on is everywhere – in lawns, pastures, roadsides and wastelands
- it's difficult to distinguish from the 2 other casebearer species so identifying it is challenging
- there are no tools available (like pheromone traps) to find or eradicate it.
What you can do
The Foundation for Arable Research (FAR) has information about managing this pest in red clover seed crops.
- Call FAR on 03 345 5783
- Check for information on its website
The adult red clover casebearer moth is about 8mm long.
The mature casebearing larvae have a clover petal case around them and are typically 6mm to 7mm long.
Signs of moth damage are visible as holes bored through the sides of florets, chewed seed and insect droppings inside the flowers.
Larvae feed on developing seeds
Adult casebearer moths lay their eggs on red clover flower heads and when the larvae hatch, they feed on developing seeds in the florets over summer.
Older larvae build a case around themselves from dried flower petals and continue to feed on seeds inside the florets. Over winter, the mature larvae shelter beneath the soil or in leaf litter and come spring, emerge from a pupa as adults.
Find out more about the moth [PDF, 745 KB]
Who to contact
If you have questions about the moth, email firstname.lastname@example.org