These holes are in the sandy part of Sumac Prairie – a very steep rocky bluff prairie on a south-facing slope. The holes vary in size from 1/8″ to 3/8″. According to Charley Eiseman, they are made by Wolf Spiders – Geolycosa sp.
11/10/2009 This is the largest hole. The lip is made from birch bark and Eastern Red Cedar needles.
11/2/2009 There are also tiny balls of sand grouped near the holes.