These are natural hard wood pieces. Logs measure approximately 6" long x 1/2" to 1-1/2" diameter. Most still have stringy, paper-like bark left on so your bird can peel, shred and chew! These work great for making toys, as the swing perch and as toy bases. Our company harvests this hardy bird-safe wood several times a year from a renewable source so our supply is fresh with a nice variety.