Wood-boring wasps may be difficult to remove from Ledbury’s iconic building, the Market House, and also from the half-timbered town council offices, in Church Lane.

A fresh scientific report carried out at the request of the town council by Rideout Associates, a division of Scientific and Educational Serves Ltd, found that fine wood dust was “erupting from holes that were about 1cm in diameter” at various locations in the Market House, which dates back to the seventeenth century.

Similar piles of wood dust were found at the town council offices.

The report by consultant Dr Brian Ridout states: “This damage was caused by wasps. We managed to find some dead specimens in debris and found them to be ectemnius cavifrons - a solitary wasp

“These insects are called salary wasps because individuals do no co-operate in nesting behaviour, unlike familiar wasps that produce large paper nests. They may, however, favour a particular site so that a population becomes established.”

This appears to have happened with the two ancient buildings in Ledbury, and the presence of the wasps indicates that the insects are taking advantage of decayed wood, not healthy wood.

Dr Ridout’s report states: “The dust is discarded from the construction of the gallery and the wasp is not able to burrow into sound wood. These wasps are therefore living in decayed timber and not causing fresh damage.

“Eradication would be difficult because the wasp galleries are probably deep in the timber.”

Insecticide paste might control the problem “if the insects become a nuisance”,

The wasps certainly made headlines back in 2006,when repairs to the Market House cost the town council a whopping £200,000 to put matters right.

At the time, the 17th century building, which is Grade I listed, was hydraulically lifted above its sandstone plinths, so that the decayed wood of the pillars, where the wasp were nesting, could be repaired with special grout.

Because it was important to keep the timber-framed building level, for both the raising and the lowering, laser beams were used as precision measuring devices.

The latest infestation was scheduled to be discussed at this week’s full town council meeting, on Thursday evening.