A long-running fight to eradicate timber-destroying termites has finally achieved success.

IT took almost three decades, but the UK’s Termite Eradication Programme (TEP) recently announced eradication of the UK’s only termite population 27 years after huge numbers were discovered affecting properties in Saunton, North Devon, in 1994. 

The culprit found in Devon was Reticulitermes lucifugus grassei, well outside of its normal southern-European distribution. For a long time, termite control experts feared the UK’s TEP was never going to succeed and that timber- and wood-destroying termites would join other pests like wasps and physical problems like rising damp in a perennial blight of buildings. However, Dr Ed Suttie, who was involved with TEP since its inception in 1998, was able to announce ultimate success shortly before Christmas 2021, 10 years after the last termite was detected. 

Termites, which resemble large white ants, will probably be a mystery to most people in the UK, as will the fact that one species was in North Devon destroying standing timber and the timber components of buildings. Indeed, I had forgotten all about it until the eradication announcement reminded me of a visit I had in December 2003 to the Silwood Park Campus (Berkshire) of Imperial College London, to meet with PhD student Laetitia Lainé. She was conducting extensive laboratory work and field trials in association with Ivan Paulmier of the Centre Technique du Bois et de l’Ameublement (CTBA) at Bordeaux in south-west France. This made sense because the south-west region of France, where between 75 and 100 per cent of towns and villages are known to have termite infestations, knows all about the consequences of allowing these insects to establish and spread. 

Funded by the Forestry Commission, the PhD project concentrated on biotic and abiotic termite preference for colony establishment. The main focus was on Reticulitermes lucifugus grassei, the termite species in Devon, although perversely it was endemic to the warmer and drier conditions of southern France. However, the project was also studying Reticulitermes santonensis (now called Reticulitermes flavipes). This species has a more northerly distribution in France, including Paris, clearly in closer proximity to the UK. Increasing vehicular access between the UK and France was thought to make this termite of high-risk potential for future introduction to mainland Britain. 

Subterranean termites generally infest wood that is in contact with the ground, including trees and buildings. They attack the soft spring growth of damp wood and the foundations of buildings, where they tend to form pockets of infestation. Tunnel construction above ground enables termites to pass from one building to another, with termite pockets becoming cut off from the colony forming another self-perpetuating colony. Observations made at the time in Devon showed widespread infestation of pine and silver birch (Betula pendula) stumps, as well as in the structural timbers of local dwellings. 

Research was in its early days, but a trawl back through my records showed Laetitia Lainé already had significant findings in relation to termite food preferences from a three-way comparison using English oak, Scots pine and common beech.

I recall Laetitia saying: “Reticulitermes lucifugus grassei had a significantly superior survival rate on oak and Scots pine compared with R. santonensis, although there was no statistically significant difference between the two in their survival rates on beech.” 

It has taken a long time to eradicate what could have been a long-term disaster for both forestry and the construction industry. Indeed, anyone who has lived in countries where termites are endemic, including the south of France, southern United States and many parts of Australia, knows full well the consequences of not conducting a continuous programme of termite prevention and control. By law, homeowners have to show a ‘termite-free’ certificate to the purchaser when they sell and ensure all building work is certified ‘termite proof’.

Forestry Journal: Termites, which resemble large white ants, will probably be a mystery to most people in the UKTermites, which resemble large white ants, will probably be a mystery to most people in the UK

Dr Ed Suttie said TEP is now in “decommissioning mode”. He commended affected property owners in Devon for “amazing” cooperation over such a long period of time. During that time they could not carry out most home improvements and were forced to allow ‘timber bait’ stakes in their gardens to monitor the termite population.

Fortunately, most of the UK is far too wet for the establishment of subterranean termites, but special circumstances in Devon, including the mild climate, a well-drained sandy soil and proximity of termite-friendly maritime pines to the affected properties, contributed to colony establishment.