I have a masonry wall that I'd like to hang a 2x6 on (6 side against the wall) so that I can use it as an anchor for a curtain rod. I would then like to stucco around it. I was wondering if it's okay for stucco to be in direct contact with lumber. The lumber will be prominent even after the stucco is applied as I don't plan to make them flush, so aesthetics is not an issue.
It is fine for stucco to be in contact with the lumber. But if you are stuccoing over the lumber, you will need to protect it with a wrap and then the wire mesh for the stucco to hold on to.
For a clean and neat appearance you might want to consider installing a "J" channel along the 2 x 6's bottom edge. This is a length of metal roughly shaped like the letter J in profile. This is used for a three layered stucco system. It covers the stucco's edges for a clean and straight appearance. Sold in 10 foot sections. It would also compensate for any movement between the two dissimilar materials (wood and cement) and prevent cracking.