Originally found from a coaster idea, turned into a rug idea from Martha Stewart Crafts.
Here is another person who decided to take this on!
1. Cut felt strips, about 16 inches long and 1/2 inch or 1 inch wide, from 3 colors of felt (cut 14 strips in tan, 12 in medium brown, and 5 in dark brown for a trivet that’s 5 1/2 inches across).
2. Starting with a tan strip, apply a dab of fabric glue 3/4 inch from 1 end. Begin rolling felt strip tightly over the glued area, pressing to secure. Continue rolling, applying glue as you work, until the coil measures no more than 1/2 inch across. (If the coiled center grows too large, the trivet will begin to resemble a bull’s-eye rather than a stump.) Snip off end of felt strip.
3. Apply fabric glue to 1 end of a medium-brown strip. Position end at the snipped end of the tan coil, pressing to secure. Wrap medium-brown strip 1 or 2 times around tan coil, applying glue as you work. Snip off end of felt strip.
4. Continue to wrap felt strips around coil, alternating colors, 2 to 4 times for each tan strip and 1 or 2 times for each medium-brown strip, until stump reaches 5 to 7 inches in diameter (3 inches for coasters); end with a medium-brown strip.
5. Wrap 2 or 3 dark-brown strips around trivet or coaster, gluing as you work. To create a textured-bark effect, cut dark-brown felt strips into 1/2- to 2 1/2-inch-long strips; layer on outer edge of trivet or coaster, gluing as you work.
You can find everything from the original post here.