Integrated pest management at Mottisfont

Vicky Hand, Conservation Assistant Vicky Hand Conservation Assistant
Carpet beetle damage to the ermine of the Whistler room curtains

Collections at Mottisfont include a wide range of object types and materials, such as painting, paper, photographs, furniture and panelling, textiles, metalwork, glass, ceramics and stone. All these objects and materials will deteriorate at different rates, due to the effects of the environment in which they are stored or displayed. The main environmental factors or ‘agents of deterioration’ are temperature, light, UV, relative humidity, pollution, physical damage or abrasion, mould and insect pest damage.

The house team use preventive conservation techniques to control and monitor these environmental factors as much as possible. The aim is to slow down deterioration of our collection, allowing them to be enjoyed by future generations of visitors.

Here at Mottisfont I'm in charge of Integrated Pest Management (IPM). This involves the monitoring and control of insect pest population in the showrooms and collections storage areas. It's important because insufficient monitoring and control can allow pest infestation to develop unnoticed, leading to insect damage to organic materials such as paper, textiles and wood.  

Fortunately, only a tiny proportion of insects in the UK attack/eat historic material. However, a small percentage of these species have the potential to become serious pests and can cause irreversible damage to collections in a short period of time.

Have you ever wondered what the little black boxes in corners of rooms or fireplaces are?  

Sticky blunder traps help us monitor our pest population
A sticky blunder trap in a fireplace at Mottisfont
Sticky blunder traps help us monitor our pest population

We monitor insect pests by not only recording ones found in our day-to-day housekeeping routine, but also by using sticky blunder traps. These black boxes house removeable sticky pads, trapping any insects that are wandering around. We then collect all the traps every quarter and identify and record any pests found, giving us an indication of population numbers and possible infestations. 

The main insect pests found at Mottisfont are:

  • Carpet beetles (varied, Guernsey and two spotted varieties), and the brown house moth: their larva will eat and damage textiles
  • Furniture beetles (commonly known as woodworm) and deathwatch beetles, both of which are wood borers
  • Booklice and silverfish, which can eat and damage paper and books
Pests caught in a sticky blunder trap
Insects caught in a sticky blunder trap
Pests caught in a sticky blunder trap

This is an example of a sticky trap collected here at Mottisfont, showing the different types of insect pests caught. As you can see some are very small, so we have a microscope to help us identify these pests.

A close look at some of the pests found in a trap
Insect pests caught in a trap
A close look at some of the pests found in a trap

If the pest traps indicate there is an increase in pest activity there are further measures that we can carry out.

Firstly, we would look at the housekeeping routine to see if it could be increased and if there are any areas that are missed, such as under curtains or behind radiators. Lures such as pheromones or attractants can be added to traps to decrease the population. Conservation grade constrain insecticide can be sprayed to affected areas and window frames to prevent entrance. We have also used desiccant dust insecticide, which can be put around the edges of rooms/carpets, and aerosol insecticidal foggers; both can be used to kill any insect activity.

Infested items and objects can also be treated individually. An example of this is the conservation of the Whistler Room curtains, which have recently been frozen (below -30 for two weeks) to kill the carpet beetles, larva and eggs before further conservation work can take place.