This cat tree was described as one that could be kept outdoors. I even stained the wood with Thompson's Water Seal to protect it, although it was supposedly pressure treated pine.  However, after a few rains, one of the sisal posts broke in half (see picture) and mold is also growing in the grain of the wood. The posts are not 100% wood, just cardboard covered in sisal rope.  I've only had the tree for a month - pretty disappointed with this product.