Suckers!

It is interesting, but also quite scary, how we are now regularly seeing introduced species bringing in their own associated introduced species with them!

In my garden, I came across these “swellings” on a Bay tree in the back garden. Well, it’s not actually my tree, but a large one that leans over the garden fence with my neighbour – very useful for cooking purposes!! 

    

A quick Google search revealed the culprit behind these swellings to be formed by a Psyllid species called a Bay Sucker (Lauritrioza alacris). Psyllids are also known sometimes as plant lice and are tiny, sap-sucking insects with very host-specific feeding preferences, often resulting in them feeding exclusively on a single type of plant.

Growths produced by the Bay Sucker

The Bay (Laurus nobilis) is one of the oldest shrubs in cultivation and has been grown in the Mediterranean region since Roman times. It was of course used as an addition to cooking, adding its own unique flavour to a range of dishes. It was introduced into this country around the 1650s and is now widely grown, certainly in the milder southern parts of the country anyway.

The little Bay sucker arrived at some point too and is now widely distributed across the country, wherever Bay grows, as this is the only plant that it feeds on.

So, no bother then as the Bay tree is an introduced species and this little sucker is host specific.

Just a thought though. At least 400 insects are known to transmit about 250 different plant viruses, and this is growing all the time. Maybe an introduced virus, carried by an insignificant host such as the Bay sucker, may not be quite so specific and spread to a really important food crop?

It might then become apparent that we are the suckers, for showing so little attention to the wide range of non-native species being brought into this country.