Friday 13 June 2014

Rosemary Beetles

For a few years I had expected the arrival of this brightly colourful leaf beetle to my garden. It has followed its food plants, which include not only Rosemary but Lavender, Sage, Thyme and related aromatic plants. As other species accidentally introduced in a non-native range, it has expanded quickly in the UK from its presumably initial introduction point at an RHS garden in Surrey in 1994. By 2005 it had spread throughout greater London and nowadays it has spread north to Scotland (see the NBN Gateway map here).
 Today, four adults were feeding on a single lavender plant in the garden. I couldn't see any others in the other lavenders, so I wondered if they were the offspring of last year arrival.
 The adult and larvae feed on leaves and flower buds and they can quickly defoliate bushes as the summer progresses.

More information
RHS page on Rosemary Beetle.


RayHolden said...

I hate that new NBN Gateway system!
I haven't seen any C. americana in my bit of S. Yorks yet, so thanks for the warning - I've experienced their destructiveness in S. London for at least the last 4 years.

However we have been seeing the equally destructive Lily beetle Lilioceris lilii in small numbers since 2003.

Candice said...

Such an interesting blog.

Africa Gomez said...

Thank you Ray and Candice,
I also have the lily beetles. I do lots of squishing on sunny spring days when the new adults come out, before they can mate and lay eggs. Still, they always manage to lay some. Now it is the time of the year to look for eggs and young larvae if you want your lilies to survive. Good luck!