What causes rot?

[maa. melee]

Wood can rot in air and water. A sterile piece of lumber can rot in distilled water. What actually causes rot?? Microbes? Fungus? Water soluable biological 'glues'?

[ssor]

Short answer: wood destroying fungus. Longer answer: with adequate moisture and warmth. The fungus won't grow if it is too cold or dry. Some fungi are species specific. that is they will distory maple but won't grow on oak. I believe that the chapter in my forestry pathology book is about fifty pages.

[ 12-12-2005, 11:03 PM: Message edited by: ssor ]

[uncas]

SSOR will correct me if I'm wrong...warm and moist yup...and the buggers don't like an anaerobic environment...or salt..
There was a thread about salt somewhere...I think way up there in the rigging...
Building and repair maybe?

pss...saw an interesting program on the lumber industry...1% deals specifically with old lumber...showed a pic. of pilings from Boston Harbor...approx 100 yrs. old...still usable...
Also...big market for lumber taken off of wrecks in the Chicago area...
Probably the wood is sold by the ounce though.. :D

[ 12-13-2005, 07:53 AM: Message edited by: uncas ]

[ssor]

Most fungi is rather fussy about the condition in which they will grow. That's why mushroom growing isn't for everyone.

I have the local tree men dump a load of chip for me every couple of years( I use it for mulch) and it is interesting to watch the variety of fungi grow on these piles with one following another for a couple of years. The first one to show looks like a dog vomited on the pile. It shows up without warning and within a week is completely gone and a bit later something else shows up.. The chip loads are always a mix of several tree species and it all rots down but in doing so it grows different mushrooms around the pile.

Edited to add:
Uncas you're right about salt inhibiting fungus growth, that is why seashore drift wood lasts so long. A tree that falls on shore will be sprouting mushrooms within a year or two but I don't recall ever seeing mushrooms on driftwood even when it has been dragged into someones garden. Further fence posts and mail box posts rot off at the groung level but if you dig up the stupm it is still in pretty sound shape. So anerobic conditions don't support fungus growth at a rate that matters.

[ 12-13-2005, 12:00 PM: Message edited by: ssor ]

[sdowney717]

I have also wondered if bleach kills rot spores.
I know it kills rot.
Rot also grows in the cold, anywhere above freezing.
Different types of rot attack different parts of the wood. Some only eat the lignin, some eat only cellulose, some dont even need the wood to be wet, mycelial filaments carry the water like a root to the plant. Once it gets going in a soft wood it spreads extremely quick, one season is all it needs to destroy a piece of white wood.
http://alsnetbiz.com/homeimprovement/woodrot.html

It can get bad enough in the closed cabin of a boat to smell like mushrooms.

Has anyone repaired a plank by using a rotary wire brush to
strip out the rotten wood
bleach the wood,
dry it
seal the raw edges with epoxy
make up a filler of epoxy and little pices of wood
fill in the holes and missing chunks.?

I have a plank where the edge has gone soft and I plan on doing this. I have lots of time and feel like not spending money for a new piece.

[John Bell]

Yes, bleach (sodium hypochlorite) will kill spores. But like any other microbe killer, you have to get enough concentration and contact time for it to do any good. If the little beasties are buried insided a substrate like wood, this gets very hard to do.

I could go into more about spore control from the standpoint of sterilizing paper for liquid packaging, but beyond the simple kill = concentration + contact time, it's not all that relevant.

[Thorne]

Check out the Smith & Co. (aka Rotdoctor) website and products. The go into a lot of detail for the process you described, and have a great cold weather CPES product.

Mr. Smith prefers MEK for the sort of "sterilization" and prep-work you mention, but of course you need to use it outside on a windy day and wear a respirator -- same for the cold-weather CPES.

http://www.smithandcompany.org/

That said, there is only so much you can do to repair rotted wood, and replacing it with material that is stiffer and possibly more brittle can be a problem when the planks swell and flex.

[ 12-16-2005, 09:51 AM: Message edited by: Thorne ]