While it probably does not qualify as rot yet, the black spots do show water is getting to the wood. Sand the blocks a bit and apply several coats of epoxy. One coat is generally not enough to fully water seal the wood.

: Several months ago, I epoxied some little wood blocks onto the floor of my
: kayak. To these, I attached some padeyes in order that I could then secure
: an anchor or other items to the floor of my kayak in order that they stay
: in one place while rolling. I have used my kayak a few times since, but
: not a whole lot. Anyhow, the other day I noticed that the blocks (which
: were probably made of yellow pine) have numerous black dots on them. I
: hope this is not some sort of rot but am not sure what else it would be.
: Before I mounted them I coated them with a thin layer of epoxy...sort of
: rubbed it in as much as slathered it on. Anyone have any ideas about what
: is marring my pine. If it is some sort of rot, is it something I should be
: concerned about or that I should do anything about. The blocks are in an
: inconspicuous place, so cosmetics are not so much of a concern.

: Thanks,
: Dave Walker
: CLC 16