The suggestion that the Mosquito, being made largely of wood, would have
made a good "stealth bomber" is brought up every now and then.  It's a
myth.  It's true that wood absorbs some radio waves, but it also reflects
some and transmits some.  The Mosquito showed up perfectly well on radar,
mainly because the waves that passed through the wood reflected very well
off the metal internal structures -- framework, wing spars, bomb racks,
cockpit, and (especially) engines.

On modern stealth aircraft, the cockpit in particular is still a problem;
most canopy materials are almost as transparent to radio waves as they are
to visible light, and the complex shape of the interior of the cockpit (not
to mention the pilot, especially their helmet) is an excellent radar
reflector.  The materials used for canopy coatings are among the most
secret parts of stealth designs (see C.10).

It would, however, have been possible to built a stealth aircraft out of
wood, if (unlike the Mosquito) it was designed with stealth in mind from
the start.  The Germans tried it with the Horten Ho IX flying-wing fighter,
which (besides its tailless design, which helped a lot) was constructed
with special glues and coatings designed to absorb radar.  Presumably the
same would have been true of the Ho XVIII bomber.  (See E.1 for further
details.)