Carded wool is also known as roving wool (or even wool batting). During carding, the wool fibers are cleaned and combed to form long linear strands (called sliver) that can then be worked into yarn or felt. Carded wool is light, airy and easily manipulated.
This roving wool comes from The Fiber Warehouse, America's oldest woolen mill. From 1884 to 2009, the Wilde Wools, Inc. mill produced a wide variety of high quality woolen fibers. When doors finally shut in 2009, Dan Fawley, the former mill owner's son, bought a small part of the business. He now specializes in fine carded Romney and Merino sheep's wool and still produces from this historic mill in Philadelphia, PA.
Nine colors are available. Brown, Fawn, Gray and White are all natural. Wintergreen, Cranberry, Flesh, Cobalt and Chestnut are dyed. Sold in 4 ounce bundles (you need about 1 ounce to create a small hand-felted acorn).
Wintergreen if the bottom center color in the above picture.