woodworm grub

[lou]

I have found a tiny white grub lurking behind a sliver of wood on our 560 year old plank and post oak panelling. The panelling is pretty decrepit at the base but had looked OK where the sliver came away with only few holes which I had, optimistically, hoped were signs of a long gone infestation. Can anyone advise what I should do please? Is this a job for Rentokil?

 

[MdB]

A photo of the grub and the panelling would help people like Matt Green a lot.

The fact that you have a grub tells you that the wood is rotting as the grubs need rotting wood as a food source. The wood will be rotting because it is damp. In my very inexpert view, you need to find out why your panelling is damp and cure that.

Spraying will just fill your house with noxous chemicals and won't penitrate to a depth to kill the grubs. It will also probably cost a lot of money and do a lot of damage to your house (if panelling etc is removed). Curing the damp problem is far better solution.

 

[Matt Green]

Bless you MdB, larval IDs are very tricky, but I'd have a go.

One up side is that the larvae was found in a sliver of wood, not the paneling itself. The chances are there is more sapwood in the sliver than in the paneling that is likely to be good quality heartwood. One larva in one piece of off cut carpentry is reason to get worried in any fashion.

 

[lou]

Unfortunately the sliver came off the panel while extracting old nails from it. The panelling has been uncovered after years of sitting behind painted tongue and groove - probably Victorian - and is in very poor condition at the bottom. The sliver came from what looked like very solid old oak on its good side. The back of the panelling in the room behind was once limed and is pretty rough. Can't upload photos as they are too big but will try and take some today and post them on Weds.
The grub met a grisley demise but was white with a darker head and tiny - about 20mm

The house was boarded up for many months and got very damp before we moved in and I'm sure it can't have done the wood much good being boarded up all those years but, as I say, it looks fine and feels really rock hard where the sliver came off.

What should I do? ! These are post and plank boards - sometimes called muntin boards I think and date from around 1430.

 

[Penners]

Is this any help?

Woodworm (anobium punctatum) larva:

 

[biffvernon]

Ahh...Isn't she sweet.

 

[Penners]

She? Young Wilfred Woodworm won't be happy with you.

But he's at peace with his sexuality.

 

[lou]

very amusing! yes - that looks like the little blighter. And, no! S/he isn't sweet at all - and must die! But how?

 

[Penners]

Received wisdom says that woodworm will only survive in damp timber. So dry out the timber and the woodworm will go off and bother some other poor soul.

But if you wish to commit anobiocide, then I understand that the least toxic chemical to use is borax: http://www.boron.org.uk/boron_in_water.htm

 

[lou]

Thanks Penners. I'll post pics of the finished articles in about a year's time when I've finished the whole job!

 

[Schoolmarm]

20mm is HUGE for a grub :shock:

 

[biffvernon]

Received wisdom says that woodworm will only survive in damp timber. So dry out the timber and the woodworm will go off and bother some other poor soul.

Drying out the timber will more likely result in a slow lingering death. Actually, at this time of year, it is more likely to stimulate pupation and subsequent emergence of imago. Either way, the worm will be gone.

 

[biffvernon]

20mm is HUGE for a grub :shock:

Yeah, that's no common or garden Anobium punctatum.

 

[lou]

OOps! about 2.5mm. So the general idea is just wait it out and keep my fingers crossed that they little b**gers crawl out and disappear this year and don't come back?

 

[worms]

and you did say darker head than body...

 

[lou]

We think so... I should have looked more carefully but I am pretty sure it did. Does that indicate something more or less sinister?

 

[worms]

Does that indicate something more or less sinister?

I can't answer that, but to me it would suggest that it might indicate something different! Penners' picture is of a typical Anobium larva and if yours had a darker head, then that probably suggests that yours was not woodworm.

Remember that common things are common and there are more harmless insects sharing our living space than sinister ones!

Anyway, who ever worried about ONE woodworm!

 

[lou]

Well me I suppose. I am guessing he - or she- didn't burrow her way into the wood all alone. I am getting the feeling from this thread that people don't consider woodworm to be a particular problem - or at least that the cure is worse than the illness. But it's such a lovely, if slightly down at heel, old panel, that I would hate it to succumb to an invasion of beasties when I could have done something about it.

 

[Penners]

I am guessing he - or she- didn't burrow her way into the wood all alone.

You're quite right. In fact he/she didn't burrow into the wood at all. It was mum who sort-of did that, by laying the egg(s) into open pores, split grain or existing flight holes in the wood.

Young master/miss grub then spends 3 or 4 years munching away on your delicious timber, before pupating and tunneling out of the surface of the wood, in order to pursue romance, marriage, hanky-panky - and to start the egg-laying cycle all over again.

 

[JoceAndChris]

Well I'm going to come clean and say I'd have zero tolerance for any beastie in my precious medieval panelling. I have zero tolerance for any beastie in my stolen supportive kitchen beams, or my top bedroom beams, come to that. They are vacummed to within an inch of their life with the soft brush attachment on the vaccuum. They are waxed. Their room is heated, and ventilated, and they are watched. If I found a grub, I'd paint on Borax.