Andrew Gabriel wrote:
In article ,
The Natural Philosopher writes:

Rusty wrote:

Isn't this confusing wet rot with dry rot. Dry rot brings its own moisture
in from its roots just like ivy, hence the name.

It does not.


It does actually. It needs a source of moisture to germinate and
grow, but once it starts, it can carry the moisture it needs from
the source (which must be maintained moist) to distant dry timber.
(I wouldn't use the term 'roots' -- they're hyphae in the timber.)
If there is a very copious water source available, you can sometimes
see the hyphae that carry it away 'leaking' tiny water droplets,
possibly on the off-chance they are next to a nice piece of susceptable
timber. I've also seen some suggestions the hyphae can extract moisture
from the air, but I suspect this may just be confusion as a result
of seeing the tiny droplets of moisture on the hyphae.

The hyphae pass this moisture as a cellulose disolving enzyme
into the dry wood, and hoover up the cellulose in order to grow
more hyphae. The removal of the cellulose causes the wood to
shrink (hence the cubing/cracking effect), and most significantly
lose to all its strength which is provided pretty much entirely
by the cellulose.

Dry rot is not native to the UK, and can't grow in our outdoor climate,
only in the micro climates which form inside buildings. It is native
to the caves in the Hymalyas, where it feeds on the tree roots which
come through the rock crevices. It was brought back to the UK in
the hulls of wooden ships, and probably got to infect some of the
merchandise or packing cases which were then carried across the UK.


Interesting ... how does it get into ones house?

I have a very old property, damp and previously poorly maintained ... I
was surprised (and err relieved) not to find any when we gutted it a few
years back.


Alex.