The establishment of the Rosemary Beetle in Essex 2001-2005
Paul Mabbott 49 Endowood Road, Sheffield S7 2LY; paulmabbott@blueyonder.co.uk
The September 2002 Newsletter noted the establishment of the Rosemary beetle
Chrysolina americana (L.) in England and suggested that its appearance in Essex was
imminent. In fact, it had already been found by Dan Hackett at the Springfield Marina
on the Lea Valley during 2001. Despite becoming common in London and Norfolk,
there was only one Essex observation in 2003, at Grays. In the spring and early summer
of 2004 it appeared in Leytonstone, Loughton and Chafford Hundred. During 2005 it
was found in Canning Town, Dagenham, Brentwood and, regularly, in Grays. There
have been no reports to date (November 2005) from VC19.
Records have been on lavender and rosemary although, outside Essex, it has been seen
feeding on thyme and sage. Many species of lavender are now planted in gardens and
observers seldom comment on species: "old-fashioned" Lavandula angustifolia Mill, is
certainly a major host but there are no specific mentions of the widely planted L. stoechas
L. being infested. Indeed, I have seen mixed plantings of rosemary and L. stoechas with
heavy infestations on the former and no beetles on the latter.
Of the thirteen records, nine were received through the Essex Field Club web-site
(www.essexfieldclub.org.uk), the others were provided by Andrew Salisbury at RHS
who is co-ordinating records nationally (and whom I thank for exchange of records).
The web-site has proved its usefulness, as Peter Harvey noted in the 2004 Essex
Naturalist, not just by mapping occurrence in Essex but also in the rest of Britain. It has
provided almost one third of the UK records including the first one from Scotland.
There seems to have been no problem of identification. The only likely species to cause
confusion is the smaller, less pitted Chrysolina cerealis L., a rare species of montane
grassland found, in the UK, only in Caernarfonshire.
It will be useful to receive further observations of the rosemary beetle including more
details of host plants.
Sea walls at Fobbing
Ken Adams 63 Wroths Path, Baldwins Hill, Loughton IG10 1SH
The old sea walls that formerly walled-off Fobbing Creek are now effectively inland,
the Creek itself having been inned by the construction of a barrier, after the 1953 floods.
They are famous as one of the last refuges of the Least Lettuce, Lactuca saligna, which
has inexplicably disappeared from virtually all of its former haunts in Britain. The inland
faces of these walls are stepped. They are so regular and parallel, that being relatively
recent in origin, I used to think that the steps (known as terracettes) might be related to
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Essex Field Club Newsletter No. 49, January 2006