A mixture of equal parts of peanut butter, bacon grease, raisins, roman meal and rolled oats was used as bait. Rolled oats or coarsely ground scratch feed was used in areas where insects removed the mixture from the traps.

Rodents trapped by me were variously prepared as study skins with skulls, as flat skins with skulls, as skeletons, as skulls only, or as alcoholics. Representative specimens were deposited in The University of Kansas Museum of Natural History. In the course of my study, traps were set in the following areas:

Morfield Ridge

In July 1959 a fire destroyed more than 2,000 acres of pinyon-juniper forest (Pinus edulis and Juniperus osteosperma) in the eastern part of the park. The burned area extends from Morfield Canyon to Waters Canyon, encompassing several canyons, Whites Mesa, and a ridge between Morfield Canyon and Waters Canyon that is known locally as Morfield Ridge ([Fig. 1]). Beginning on September 4, 1961, three pairs of traplines were run on this ridge at elevations of 7,300 to 7,600 feet.

Vegetation in the trapping area consisted of dense growths of grasses and herbaceous plants, which had covered the ground with seeds. In this and in the following accounts, the generic and specific names of plants are those used by Welsh and Erdman (1964). The following plants were identified from the trapping area on Morfield Ridge:

Lithospermum ruderale
Chenopodium pratericola
Achillea millefolium
Artemisia tridentata
Aster bigelovii
Chrysothamnus depressus
Chrysothamnus nauseosus
Helianthus annuus
Helianthella sp.
Lactuca sp.
Lepidium montanum
Quercus gambelii
Agropyron smithii
Bromus inermis
Bromus japonicus
Oryzopsis hymenoides
Calochortus nuttallii
Linum perenne
Sphaeralcea coccinea
Polygonum sawatchense
Solidago petradoria
Wyethia arizonica
Nicotiana attenuata
Fendlera rupicola
Penstemon linarioides

Only Peromyscus maniculatus, Perognathus apache and Reithrodontomys megalotis were taken in this area ([Table 1]). Many birds inhabit this area, including hawks, ravens, towhees, jays, juncos, woodpeckers, doves, sparrows and titmice. Rabbits, badgers and mule deer also live in the area. Only two reptiles, a horned lizard and a collared lizard, were seen.

South of Far View Ruins

Two parallel trap lines were established on October 4, 1961, in the area immediately south of Far View Ruins ([Fig. 1]). In altitude, latitude and geographical configuration the area is similar to that trapped in the Morfield burn, but the Chapin Mesa site had not been burned.

Canopy vegetation is pinyon-juniper forest. A dense understory was made up of Amelanchier utahensis (serviceberry), Cercocarpos montanus (mountain mahogany), Purshia tridentata (bitterbrush), and Quercus gambelii (Gambel oak). The ground cover consisted of small clumps of Poa fendleriana (muttongrass), and Koeleria cristata (Junegrass), intermingled with growths of one or more of the following: