Deathwatch beetle

[Schweiz]

Hello,

First post here, and sadly not under happier circumstances.

Grade 2*, 15th century former hall house, completely encased in Georgian brick and extended upwards and outwards in countless phases over the last 500 years. We’ve been here 9 months. The previous owners were very much of an “out of sight, out of mind” mentality and we’ve been catching up with a lot of things which have been neglected for 20 years.

The house was derelict for 2 years from 1969-71 and there is a lot of historical woodworm from this period and earlier. Unfortunately it has become apparent over the weekend that we have active deathwatch beetle. We’ve hear the calls and have found around 30 live and dead beetles on all three levels of the house.

The house is currently warmer and more water-tight than it has ever been. The previous owners left the top floor and several other rooms completely unheated for years and there was water dripping down some wall internally, and of course between the brick facades and timber frame.

My initial thoughts were that we should adopt a wait and see strategy, based on the hope that these were residual beetles and that the eggs that they lay would not develop due to the drier conditions. I’m now less sure. The number of beetles, and the fact that they seem to be emerging all over the place has tempted me to call a treatment company tomorrow. We’re concerned of course about the cost, disruption and chemicals.

I’m sure the topic is a regular one on this forum so I thought I would ask if anyone has any advice.

Cheers
Schweiz

 

[Feltwell]

I haven't seen him on here for a while, but you may wish to send a private message to Matt Green - Entomology & old buildings are his area of professional expertise.

 

[MikeG]

Do you actually recognise the beetles as death watch beetles? I only ask because this is the time of year that you'll start to see loads of other beetles. We've one around here that people call a strawberry beetle which occurs by the hundred right now.

 

[Abi Cott]

How far north are you? It seems a little early for deathwatch to be so active. Particularly after such a harsh winter. However I'm a fair way north and only have minimal experience of them in one "rented" property.

I second the suggestion of contacting Matt Green. He's good at this stuff and very helpful.

 

[Schweiz]

We're certain that it's deathwatch having looked at them under a magnifying glass and compared to online photos. The knocking is also fairly distinctive and we've been able to play a recording of a knocking beetle and got a response from a beetle inside a wall cavity.

We are in Staffordshire. It is quite early but it has also been unseasonably warm. There are plenty of other beetles, particularly woodlice and the spiders are out in vengeance.

Chemicals seem very out of vogue with conservation and preservation people, but predictably commercial experts are still pushing this approach.

I will have a look and see if I can contact Matt Green as recommended. Thanks for the hint.

 

[Toby Newell]

Hi

Your house sounds wonderful. I have little first hand experience with deathwatch but dozens of experiences hundreds maybe with common furniture beetle (woodworm) as I restore timber for a living.

I tend to tread very lightly with woodworm as you say drier conditions normally do the trick but from what I hear (This could be received wisdom) with deathwatch you absolutely want to be cautious.

I would certainly contact someone asap and don't ignore it. Most people on here are very helpful so if they say Matt is the man then try him first.

 

[88v8]

Hello and welcome.
Edit your Profile to show your location.

Death watch has a larval stage of up to twelve years.
I have found Cuprinol Five Star effective against woodworm, but of course only if one can get at it.

The National Trust uses Constrain
http://www.historyonics.com/insecticide.htm

Eventually I suppose, pests will become resistant to it, but currently it seems to be the go-to. I would however seek Matt's assistance, or failing that another trained old-house specialist.

Ivor

 

[GPHouse]

The one everyone recommended to me for deathwatch was the Sovereign Chemicals Permethrin based woorworm solution with an emulsion (deep Kill) for non visible areas.

Permethrin is a contact killer which means you only get the beetle as they surface, or you have to inject or microdrill (bad plan in my opinion) beams / walls etc to trea deep in the timbers.

Boron based sprays and disrupt the beetle s ability to digest and kill them sloy as they bore/ eat.

Permethrin is BAD for other wildlife too so go carefully!

I have to say I cant vouch for the effectiveness but 2 years on I am spraying again as a top up / in the hope of catching them off guard!

 

[a twig]

We had deathwatch in our roof, thanks to some leaks and a valley gutter that flowed the wrong way.

Roof was repaired about 4 years ago, and shot timber was replaced. No treatment applied, as consensus of people I spoke to at the time was that unless you were going to individually inject treatment into each hole with a syringe, the sprays etc wouldn't soak into the old timber enough to make a difference.

Main cure agreed on was to ensure that the timber is dried, then it is too hard for the larvae to eat, and they die off. Once the roof was fixed, and heating was up and running again, everything dried out pretty quick.

Over the next few years we had progressively fewer beetles each spring. As the survivors became more and more desperate to find a mate they are easy to find and kill.

We had our last beetle rattle early last spring, jobs a good un