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Purple Loosestrife: Biocontrol

Biocontrol

Biological control for purple loosestrife is still in an experimental stage in California. A root-boring weevil (Hylobius transversovittatus) and a flower bud weevil (Nanophyes marmoratus) have been released at limited test sites in California with mediocre results. Other states including Oregon are reporting great success with two leaf-eating beetles (Galerucella pusilla and Galerucella calmariensis). While beetles have required up to six years to become established, in some states insects are causing substantial damage to purple loosestrife infestations. Testing has been performed in California to monitor the insect-host relationship with very good results. Permits have been requested to release these insects in California. California will continue to pursue test releases and monitoring of insects. For more details see Biocontrol Program of Purple Loosestrife.

Purple Loosestrife Biological Control Agents

Photos

Nanophyes marmoratus
Nanophyes marmoratus - Adult
Adult

Hylobius transversovittatus
Hylobius transversovittatus - Adult
Adult		 Hylobius transversovittatus - Larvae
Larvae

Galerucella calmeriensis
Galerucella calmeriensis - Adult
Adult		 Galerucella calmeriensis - Larvae
Larvae

Galerucella calmeriensis
Galerucella pusilla - Adult
Adult		 Galerucella pusilla - Larvae
Larvae

Before - Biocontrol Agent Release
Before Biocontrol Agent Release

After - Biocontrol Agent Release
After Biocontrol Agent Release

CDFA Employees Releasing Biocontrol Agents
CDFA Releasing Biocontrol Agents

Photos courtesy of Oregon State University
Eric Combs, Peter McEvoy, and Shon Schooler