MESA VERDE Big Juniper House of Mesa Verde, Colorado Wetherill Mesa Studies

The archeological survey of Wetherill Mesa was in its final season. Canyon and cliff sites had been located and recorded, and a small crew continued the survey on the mesa top. On May 6, 1960, in a rather dense section of woodland south of Mug House, two house mounds were located and designated as Site 1595. Several large junipers grew on the mounds, the largest one—about 30 feet high and about 3 feet in diameter—being rooted in a kiva depression (later called Kiva B). Although this tree was felled (along with the others) in preparation for the excavation, it impressed itself on our minds. Subsequent reference to Site 1595 as "the big juniper site" took hold and led to our naming it Big Juniper House.

REASONS FOR EXCAVATION

The decision to excavate Big Juniper House was based on two objectives. One was to provide an interesting exhibit-in-place for visitors to Mesa Verde National Park; the other, to obtain information about an inadequately understood phase of occupation in the Mesa Verde region.

Before excavation, surface pottery and architectural features indicated a transitional phase from Pueblo II to Pueblo III. As excavation progressed, we saw that one of our objectives could not be realized—the site would not be suitable as an exhibit in the interpretive program. It had been occupied continuously for some 250 years, and building styles were not clearly differentiated stratigraphically. Some rooms even showed four different masonry styles and construction periods in a single wall. Moreover, the pueblo itself did not present a coherent, compact unit. "Horizontal stratigraphy" is harder to understand than vertical stratigraphy, and visitors with little time to spend at the ruin would be baffled rather than enlightened. In discussions between the park's interpretive staff and the project archeologists, it was decided the site should eventually be backfilled. (Badger House and Two Raven House, mesa-top ruins of Pueblo II and Pueblo III, south of Big Juniper House, were picked as suitable for exhibit purposes.)

The withdrawal of interpretive interest permitted thorough excavation, usually impossible because of stabilization and exhibition requirements. Walls could be dismantled where and when needed; floors could be dug through; and backdirt could be piled wherever convenient. The work proceeded rapidly, and the second objective—to obtain information on the Pueblo II-III transition—was fulfilled.

LOCATION AND ENVIRONMENT

Mesa Verde National Park comprises about half of a large south-sloping tableland or mesa in southwestern Colorado (fig. 1). The mesa is demarcated on its north and west sides by a steep escarpment rising 1,000 to 2,000 feet above the surrounding country, and it is transected in its eastern and southern sections by the Mancos River Canyon. Headward-eroding streams have carved the tableland into northwest-southeast trending canyons creating many small mesas, one of which is called Wetherill Mesa (fig. 2). The name "Mesa Verde" (green table) derives from the perpetually green forest of pinyon and juniper that covers much of the tableland.

Fig. 1 Four Corners area (click on image for an enlargement in a new window)

Fig. 2 Aerial view of Wetherill Mesa.

The sedimentary rocks exposed in the area are primarily sandstones and shales, with intrusions of small igneous bodies and dikes (Wanek, 1959). The stratigraphic sequence runs from the Dakota sandstone (the oldest), through the Mancos shale, Point Lookout sandstone, and the Menefee formation, to the Cliff House sandstone (the youngest). Locally, the Cliff House sandstone is overlain by small bodies of cemented gravels which are probably derived from the La Plata and San Juan Mountains.

Big Juniper House is on the west side of Wetherill Mesa, approximately 380 yards due east of Rock Canyon and Jug House (Site 1233), and about 820 yards due west of Long Canyon (fig. 3). The altitude at the site is approximately 7,220 feet.

Fig. 3 Big Juniper House and other excavated sites. (click on image for an enlargement in a new window)

The site is on a low, east-west ridge that slopes in all directions. Figure 4 gives an idea of the general terrain. The greatest slope is to the south, following the inclination of Wetherill Mesa. The site faces toward the south, with the rooms on the north followed by the kivas and the trash mound.

The undisturbed soil of the site is a red loess, the bottom of which was not encountered in excavations as deep as 10 feet. The loose forest humus on the surface rarely exceeded one-half foot in depth.

In general, the climate of the Mesa Verde region is characterized by low humidity and wide, diurnal temperature ranges. Average annual precipitation over a 38-year period, beginning in 1923, was 18 inches. Two wet periods occur during the year: in late winter, with moisture primarily from snowfall, and in late summer, with moisture usually from afternoon thunderstorms. The wettest months are February and August, the driest are June and November. In 1962, when Big Juniper House was excavated, Mesa Verde National Park recorded its driest summer, with precipitation of 0.74 inches for June, July, and August. The average precipitation during these months in the 38-year period of record was 4.4 inches.

The warmest month is July, with a mean temperature of 72°F., and the maximum recorded temperature of 102°F. The coldest month is January, with a mean temperature of 29°F. The lowest recorded temperature at Mesa Verde, -20°F., occurred in January 1963.

The area of Big Juniper House is a woodland of pinyon and Utah juniper, with an understory consisting chiefly of mutton grass. Big sagebrush and black sagebrush grew on the house and trash mounds. These shrubs are commonly found on the disturbed soil of other prehistoric sites at Mesa Verde (Erdman, MS.).

Common animals observed in the area are the coyote, mule deer, bobcat, gray fox, Nuttall's cottontail, rock squirrel, Colorado chipmunk, brush mouse, deer mouse, and pinyon mouse. Badger, porcupine, and red fox are seen occasionally.

Birds observed today with varying frequencies are the scrub jay, pinyon jay, common raven, common crow, hairy woodpecker, and red-tailed hawk. Brief appearances are made by the broad-tailed hummingbird, plain titmouse, robin, western bluebird, and chipping sparrow.

Turkeys, probably domesticated or kept in captivity by the prehistoric inhabitants, became extinct in the Mesa Verde historically and were re-introduced in the park in 1944, 1955, and 1957. They are now most common near the park's staff residential areas where food is relatively abundant. However, they have also been observed in other parts of the park. They are native to, and numerous in, areas not far from Mesa Verde, such as the White Mountains of Arizona and the Sangre de Cristo Mountains in New Mexico.

EXCAVATION PROCEDURE

Excavation began by stripping soil from the center of the West House Mound to the outside until walls were found. As rooms were outlined, they were numbered consecutively (fig. 5). Levels within rooms were arbitrary or, in some cases, were by the natural stratigraphy. Artifacts from the floor or, if no floor was encountered, from the level corresponding to the base of the walls were always bagged and cataloged separately from artifacts recovered in the fill. Artifacts from floor features, subfloor tests, and subfloor features were also bagged and cataloged separately.

Areas adjacent to the rooms and kivas were stopped down in an effort to discover occupation surfaces and extramural features. Artifacts from these features were bagged and cataloged separately from those of general proveniences within the areas.

Kivas A and B, marked by circular depressions, were trenched to find the walls and then stripped down by artificial and natural levels. Kiva C was located by a soil auger, trenched, and then stripped. All rooms and kivas that were completely excavated were also tested below floor levels—usually by two trenches at right angles to each other—and dug to sterile native soil. Subfloor features were completely excavated. Artifacts from the kiva floors, floor features, and subfloor features and tests were handled in the same manner as those from rooms.

The South Trash Mound was excavated by a series of parallel trenches dug from the surface to sterile soil. The trenches were begun from the south edge of the mound and continued northward until the trash deposit played out. A long trench, Test Trench 10, intersected the other trenches at the north edge of the trash mound (fig. 163). No definite evidence of vertical or horizontal stratification was observed in the trench profiles or in the materials obtained from test blocks cut in 6-inch levels. Accordingly, in the laboratory analysis, all trash mound artifacts were considered together, except for those associated with or near burials or in other special locations.

Tree-ring specimens were cataloged, wrapped, and treated with preservatives in the field, checked through the Wetherill Mesa laboratory, and shipped to the Laboratory of Tree-Ring Research, University of Arizona, for dating. Artifacts, burials, and other material were field cataloged and then sent to the laboratory for cleaning, preservation, permanent cataloging, and study.

The plan and sections of the site were mapped by telescopic alidade and planetable, with a stadia rod. Room and kiva plans were made with a leaf alidade and planetable, and cross sections of these features were plotted with level line, plumb bob, and tape.

In the field, a 4-by-5 Crown Graphic was used for black-and-white pictures and a 35 mm. Leica for color slides. A special tripod, made of tubular steel with one leg a ladder, enabled us to shoot down from a height of 15 to 17 feet. Bird's-eye views of rooms were taken with the camera secured to a tilt-top head with a 90° piano hinge. In the laboratory, we found that a 4-by-5 view camera gave the best perspective for illustrating three-dimensional objects (Mang, 1965).