Making pews less comfortable for
wood-boring weevils
by Dr Matthew Green
Originally published in Church Building magazine, Issue 87, May/June 2004
Wood-boring weevils are relatively unknown relatives of furniture beetles and deathwatch beetles, whose damage is related to damp and fungal decay. There are several species to be found in the UK: all are very similar in appearance. They are 4-5mm in length and are slender compared with other wood-boring beetles. They have elongated snouts and are red-brown in colour. Wood-boring weevils (the most commonly encountered species is Euophryum confine) are only capable of damaging timbers that have been modified in some way by fungal damage. Whilst they do not attack sound dry wood they considerably accelerate the damage from wood decay fungi and create bore-dust that could be misinterpreted as evidence for activity of a different insect. Misidentification of weevil damage is costly, as these insects never require chemical treatment.
Weevil damage to a pew end
Ridout Associates have seen a number of churches in recent months where pew-ends are in contact with walls or pillars that are damp. Despite the usual good quality and age of the wood used in church pews, if it is constantly kept damp the surface will decay and become susceptible to attack by wood-boring weevils. Weevil damage is characterised by ragged holes in the surface of the wood from tunnels running along the grain near the surface. Damage is limited to areas where fungus has modified the wood, as weevils rarely venture far into sound timber.
Generally the presence of wood-boring weevils is symptomatic of a bigger problem and dealing with them effectively usually means solving that problem. Weevils only damage wood in buildings that has been modified by fungi and fungi only attack wood that has a high moisture content. It follows then that the best way to control the damage inflicted by wood-boring weevils is to remove the source of moisture.
St Mary's Church, Tarleton
In the case of pew-ends, isolating them from wet walls is the best way to prolong their life. This may be achieved by moving or shortening them slightly although in some cases this can be difficult. Another option is to place some kind of impervious barrier between the pew and the wall using, for example, a damp-proof membrane or similar. Removing the source of moisture affecting the wall is the long-term solution but this again can be problematic given the variable nature of ground levels abutting church walls. If possible though (by the permanent reduction of ground levels or inclusion of French drains), once the wall has dried out the fungus will not be able to continue decaying the pews and the weevils will seek out an easier meal elsewhere.
It is generally thought of as good practice to ensure that building timbers are never directly in contact with damp masonry and the same rule should be applied to all wooden items, whether structural timbers or furniture. Church pews are obviously at high-risk due to the fact that the majority of them are fixed items. Hopefully a little knowledge about wood-boring weevils will go long way to preserving timber pews.