Mungo Bulge wrote:
kind of a 'catch 22' here. Although tung oil and to the same extent
linseed oil are good protectors of wood and at least linseed oil is a
preservative of wood and both are less susceptible to the protection
failures common to varnish, they both have the same common (for lack
of a better word) failing. They are both mildew food. So keep your
kayak dry and ventilated when not in use and you will keep it mildew
free.

That's incorrect. While linseed oil definitely suffers from that problem
(I know from personal experience), tung oil does not encourage mildew. I
was told this by the people in charge of preserving the boats at Mystic
Seaport and I've verified it through other sources. That's also why I
specified using 100% tung oil, as many "tung oil finish" products
actually contain little or no tung oil and may contain linseed oil.