Wednesday, October 12, 2011

Eaten Alive!





I hate bugs that eat wood. Build a house, spend a lot of time and money and what happens? Termites move in from next door and consume your equity in short time.

I once visited an elderly client who lived alone in a very large, rich house. She was the kind of person who, in her late 80's, would wander around in this 10,000 square foot house all day, barefoot and in her nightgown. She called me about bugs in her clock.

When I arrived, I walked into the entry and noticed a beautiful early Georgian tall case marquetry clock. I didn't see any bugs, so I removed the bonnet to look at the works. When I pulled the bonnet forward a kilo of live subterranean termites fell to the floor and started crawling all over the place.

I was amazed at what I saw. Inside the bonnet was a large colony of termites, which usually don't eat hardwood furniture. Moving the case from its position at the wall I discovered a single hole in the floor, under one of the feet of the clock. The termites had eaten through the oak floor, up into the foot and continued along the body of the clock into the top, where they set up shop. The entire clock was crawling with bugs and I put it into several layers of plastic bags before I removed it for fumigation.

At the same time I had to remind the elderly lady to keep away, as she insisted on walking all over the bugs crawling over the floor.

Generally, hardwood furniture is attacked by a pest called a powder post beetle. They leave small exit holes in the surface, which serve to provide a convenient place to remove their waste, called "frass". Frass can be distinguished from fine sawdust in that it feels like small round pieces of sand, where sawdust feels more like baby powder.

There is another bug, which has a more morbid reputation. The Death Watch Beetle is so named because during the 18th and 19th centuries, when a person was on his death bed, his friends would sit through the night next to him and quietly wait his demise. Often the only sound in the room was the loud noise created by the Death Watch Beetle, as it ate the furniture.
The Death Watch Beetle is a much larger insect than the powder post beetle, and the size of the exit holes is the clue which animal you are looking at.

It is fairly easy to determine if something is actively infested. One way is to use a stethoscope to listen for the sound of the bugs as they have dinner. The easiest and quickest way is to use sun light or a strong flashlight and look at the inside edges of the exit holes with the raking light coming from the side. The holes that appear fresh indicate activity. The holes that are filled with dirt or wax or oxidized are old and the bugs have probably moved on.

These bugs are hard to kill. The eggs can survive two weeks in a vacuum. The Getty has developed a method to use nitrogen inside a bag which is able to keep the oxygen out. If the bag keeps all the oxygen out for two weeks the bugs will die. Even a single molecule of oxygen gives them a chance to survive.

I do not recommend heating or freezing antique furniture, as strange things can happen to the wood, glues and finish. Even Vikane gas is not enough to kill the eggs; only the adults.

Methyl Bromide gas applied at a certain concentration for 48 hours is guaranteed to work on all these bugs all the time. I have a company with a sealed container, where I put the furniture every two weeks to have this treatment done. It is the only way I know, and, since Methyl Bromide gas is a serious problem for the ozone layer, it is soon going to be eliminated as an option.

When I asked the customs agents why they don't require fumigation for furniture beetles as the antiques arrive from Europe, like they do for pests on fruits, they answered: "We don't care, since that bug is already here."

The bugs are going to win this war.

3 comments:

Joshua Klein said...

Have you ever tried the Ageless packets recommended by Brandon and Hanlon? http://cool.conservation-us.org/coolaic/sg/wag/2003/brandon_hanlon_03.pdf
I have yet to try it out but am very interested.

W. Patrick Edwards said...

Thank you for including the link to this AIC/WAG paper with your comment. I visited Gordon, Brian and Joe at the Getty Conservation Center in the early 1990's to see this method for myself.

I think the use of Nitrogen to flush the Oxygen continuously from the bag is a good idea. I do not trust the use of Ageless to remove all the Oxygen unless expensive Oxygen monitoring equipment is used, since the little pills supplied with the Ageless product cannot be trusted.

Until methyl bromide gas is no longer available, I will continue to use it. It does no harm to the finish, wood or upholstery, except foam stuffing. It will leave a sulfur smell on foam.

Joshua Klein said...

Interesting, Patrick. Thanks for the info! I love reading the blog!