These photos have been created by Smashing Magazine readers in our Smashing Texture Contest. What can you do with them? You can use all textures for both private and commercial projects for free, without any restrictions whatsoever. However, you are not allowed to offer these files for download; please respect the interests of over 300 participants of our contest. Please also consider the license information attached to the .zip-archives you download from our server. When it comes to usage of textures, different photographers may have different opinions and intentions.
source: http://www.smashingmagazine.com/texture-gallery-wood-bark/