Completely encircling the house outline was a poorly defined zone of yellow-brown sand which lay directly on the buried surface of the floodplain and extended upward a foot or two where it gradually blended into the upper component of the mound fill. This light-colored sand may have been banked against the outside of the house while it was still standing; or it may have resulted from uneven, subsurface staining by charcoal and other organic material of that portion of the mound lying directly above the house. In any event, it was virtually devoid of cultural material, only a very few stone chips, widely scattered, being found in it.
A well defined humic zone, resulting from organic staining after the mound was built, appeared at the surface of the mound. It averaged about 0.5 feet in thickness.
Except for the clay in the hearth and in the house floor, the entire mound was constructed of sandy soil like that of the surrounding floodplain, whence it undoubtedly was derived. The depressions on the northwest and southeast sides of the mound are probably the borrow sources for the sandy soil. The clay could have easily been obtained from exposures in the cut banks at the edge of the creek channel.
OCCUPATIONAL FEATURES
Besides the two possible borrow pits mentioned above, the only occupational feature found at Mound B was House No. 3.
House No. 3
This house was erected on the surface of the floodplain before the mound was built. The purpose of the mound apparently was to bury the remains of the house after it had burned.
Beneath the house floor zone, which was described in the preceding section, were found 59 post molds measuring from 0.25 to 1.3 feet in diameter and extending from 0.3 to 2.5 feet below the floor ([Fig. 5]). The faint gray stain of the post molds was quite dim and difficult to distinguish. They were located by cutting a vertical face completely around the house area, then carefully cutting the face inward from all sides. As the post molds were located, they were plotted on a horizontal plan and a measured profile drawing of each was prepared.
Twenty-three of the post molds formed a circular outline representing the perimeter of a house approximately 17 feet in diameter ([Fig. 5]). The peripheral molds averaged 0.5 feet in diameter and were spaced, as a rule, about two feet apart. At the southeast edge of the house were two parallel lines of three molds each which defined an extended entranceway. Because of disturbance in the entranceway area by tree roots, only the bottom portions of the entrance molds were preserved. Their arrangement suggests that some of the post molds related to the original entranceway were not discovered.
Within the external ring of post molds were 30 irregularly spaced molds, including four very large ones which probably held the bases of relatively heavy roof supports. Two concentrations of smaller post molds (one on the northeast side of the house, the other on the southwest side) possibly mark the location of interior structures such as sleeping or storage platforms. In the center of the house was a relatively large post mold, over which the fire hearth had been built. This probably represented a center post used in construction of the house and then removed when the house was completed.