Originally, barkcloth was actually made from the inner bark of certain trees, beaten flat and made into fiber.
What we think of as barkcloth, though, is cotton, linen, rayon, polyester, or fiberglass fabric made from the 1930s on and really popular in the 1950s & 1960s. It was fairly thick and sometimes nubby and had a texture to it. Even though it's thicker than a clothing cotton, it's soft and was used in throw pillow, upholstery & cushions and draperies. Here's a picture of a cornice I built & covered in a soft floral vintage barkcloth. The big curlicue pattern used to fill the blank space was common in barkcloths.
Here's a very typical color and pattern I picked up a few years ago. The burgundies, pinks & greys were really popular. In the second picture, you can see the pattern well.
This is another floral I've gotten. This type of floral always looks upside down, because there are flowers going both ways on it. The pattern, which you can see in the second picture, is totally different from the one above.
Barkcloth is being manufactured again in a variety of retro patterns, but most people really like the vintage ones the best. The fabrics can be pretty expensive (up to $40 for a good-sized piece) and often are stained or imperfect -- you just learn to work around the imperfections (just like we do with our friends)!
People are using barkcloth to make all kinds of things -- especially purses & totes. Go to www.etsy.com and type in barkcloth -- you'll see the variety! You can check out different patterns of barkcloth and shop for them here or at http://www.buybarkcloth.com.