Like your lichen

When I was an incumbent, I was sent for trial a product that cleaned the lichen off headstones without damage to stone or inscriptions. Is there any such product on the market today?

A supplementary question should be asked, "Why does the lichen need to be removed?" The British Lichen Society is actively involved in the conservation of lichens, and has a thriving churchyard project to record lichens in churchyards and give advice on appropriate management.

In Britain, the churchyard is a significant habitat for lichens (ranking in importance alongside ancient woodland, heathland, etc.), and churchyards are particularly vital for maintaining populations and diversity of those lichens that grow on stone in lowland Britain, where natural outcrops are rare. Although most yards will have between 50 and 70 different lichen species, there is an increasing number of churchyards where this number exceeds 100.

The contribution that lichens make to the appearance of the churchyard is often overlooked; but the atmosphere of the typical English churchyard is greatly enhanced by the effect of lichens forming a colour-

ful mosaic pattern on the church buildings, tombstones, and boundary walls. Lichens not only enhance the look of the stone. They may also offer some protection against the ravages of wind, rain and frost.

Cleaning of tombstones inevitably removes lichens and mosses. Brushing too vigorously, particularly with a wire brush, also removes the surface patina that has developed over a long time and gives the stone its mellow look. Although some cleaning may be necessary in order to read the inscription, only that part of the stone carrying the inscription needs to be cleaned.

There are other methods of reading inscriptions (such as looking through a tube, wetting the area, or taking a rubbing), and these should always be tried first before resorting to cleaning. If cleaning is thought to be necessary, only water and a soft brush should be used. It is inadvisable to use bleach, herbicide or algicide.

In all cases where lichens will be destroyed, the British Lichen Society would welcome the opportunity to survey the stones to be cleaned or removed, so that, if there are rare lichens involved, a satisfactory solution to the conflicting interests can, we hope, be reached.

More information regarding the British Lichen Society’s churchyard project can be found at www. thebls.org.uk.

(Mrs) Ishpi Blatchley (on behalf of the Churchyard Project, British Lichen Society)
Bromley, Kent

The Revd Neil Vigers, of Hook, also regards the cleaning of lichens off gravestones as "unintended vandalism". We pass on other readers’ advice — to use household bleach (thoroughly wet the stone first); or a strong solution of washing soda (sponge over, and wait a month or two); or Bio patio cleaner — with that caution. Editor

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