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Tackling common tansy in North America

Common tansy is an aromatic Eurasian plant species with a long history of use as a medicinal herb. Introduced for this purpose to North America, it has since become invasive. One reason for this could be the absence of the natural enemies that keep it in check in its area of origin. CABI has been tasked with identifying specialist natural enemies from Eurasia that can be introduced into North America as biological control agents.

Biological control of diamondback moth in Canada

The diamondback moth is a global pest. Canadian farmers often have use chemicals to protect their crops. This is costly and the pest is becoming immune, meaning additional control options are needed. In Europe, Asia and Africa, Diadromus collaris, is a major parasitoid of the moth. It has been introduced to several countries or regions and has established as a successful biocontrol. CABI is therefore carrying out life table studies in Europe to determine if its introduction is a viable strategy.

Finding a biocontrol for Himalayan raspberry

Yellow Himalayan raspberry is a major threat to native Hawaiian forests. A single plant can grow into a 4m tall impenetrable thicket, and its aggressive growth and rapid colonization enables it to outcompete native species. Current control methods are both labour intensive and costly. The aim of this project is to find biological control agents (both arthropod and fungal) from the plant’s native Indian and/or Chinese region of the Himalayas to control its spread in the Hawaiian introduced range.

Controlling wild ginger

Plants from the Hedychium genus are widely loved and cultivated as ornamentals but a few are threatening delicate ecosystems in Hawaii, New Zealand, the Macaronesian Archipelago (Azores, Madeira and the Canaries), Brazil, Australia and La Réunion. We are researching natural ways to manage the plants where they have become invasive, which involves returning to their original home range in the North eastern Himalayan foothills to try to find damaging and specific insects and/or pathogens which may prove suitable for release in the invaded range.

Controlling noxious Russian knapweed in North America

Russian knapweed is one of several invasive plants of rangelands that arrived in North America as a seed contaminant in the 19th century, in this case from Asia. Biological control is often a good approach for these plants, but a nematode species introduced in the 1970s proved ineffective against Russian knapweed. Funded by a US and Canadian consortium, CABI has been tasked with researching new biological control agents for introduction, some of which are already showing promise.

Protecting leeks and onions from pests

The invasive leek moth poses a significant and immediate threat to producers of leeks, onions, garlic and chives in North America. The larvae mine the green tissues, reducing the marketability of crops. The pest’s distribution is expanding, with no signs of suppression by indigenous natural enemies. We are supporting an integrated pest management (IPM) programme run by Agriculture and Agri-Food Canada to combat the leek moth using specialized natural enemies from its area of origin.