woolgathering\WOOL-gath-uh-ring\(noun): indulgence in idle daydreaming

In Wales, woolgathering, or gwlana, was a social custom adopted to provide for wives of laborers who did not have access to wool of their own to spin. It involved walking along hedgerows and stone walls and picking off wool that was left behind as the sheep had passed by. Later, after the custom was in little use, woolgathering was considered an unprofitable enterprise. It's practitioners were percieved to wander aimlessly and gained little for their efforts. Hence the association of woolgathering with your mind wandering aimlessly.
     -- Marriam-Webster Dictionary

" Origin: Approximately 1553; from the literary meaning 'gathering fragments of wool torn from sheep by bushes.' "
     --word.figureout.info

"The fact is that women woolgatherers would begin their walk as early as four o'clock and could pick up two to four pounds in a day. Friendships developed among woolgatherers as well as local farm families. These women might do chores of an evening at a farm in excange for room and board for the night"
     --From Hip to Knit by Judith L. Swartz

"I would say 2-4 pounds in a day is pretty profitable..."
     -- Me