#1: Does Wood Sink ?

Yes, it does !

Live wood sinks....try to break a twig from your garden and drop it in a cup of water! 

Live wood is heavier than water because it is water-logged.

Dry, dead wood does not sink...but it can be water-logged to sink again. 

We can water-log wood by submerging wood for many weeks.

Or in a few minutes by putting wood under high pressure in water.

See Pine wood samples in the picture above, all kept for 10 minutes under pressurized water.  The sample "AT" to the right was in water under the highest pressure (1000 PSI) and now it sinks.....!