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Communal game drives were a cost-effective way for pedestrian hunters to obtain large amounts of meat and hides. Although once common across North America, nearly all traces of game drives have been removed by modem agriculture practices. Thus, the two high-altitude sites in Colorado reported on in this volume are significant because their features are largely intact and their occupations can be reliably dated. Chapter 1 is a thorough overview of ethnohistoric game drives and hunting practices across North America. Chapter 2 focuses on the Trail Ridge Game Drive site located at the forest-tundra ecotone at 3,4653,500 m asl. Natural topography and constructed stone walls were employed to funnel herds to hunters waiting in blinds. Pellet-group studies suggest that the intended prey were elk or mule deer. Projectile points indicate intermittent occupation between the late Paleoindian and late prehistoric periods. Charcoal from two blinds was radiocarbon dated to 4590 ? 60 B.P. (Beta-85363) and 2610 ? 60 B.P. (Beta-75998), while granite weathering dates indicate that the walls were built or repaired numerous times. Chapter 3 discusses the extensive Flattop Mountain Game Drive site situated at 33503720 m asl. Features include 14 stone drive walls, 848 cairns, 90 blinds, and a possible hunter's bed. Numerous projectile points ranging from Paleoindian through protohistoric styles have been recovered in this vicinity since the 1920s, and these, as well as all other lithic tools, pottery and debitage, were analyzed. Fifteen radiocarbon samples collected within blinds date between ca. 4300 and 200 B.P. Chapter 4 places the two sites within a continental perspective. Both were used intermittently beginning in the Paleoindian period, and their features were maintained by various parties up to the protohistoric period. The appendixes address lichenometry, granite weathering, radiocarbon dating, pellet-group surveys, early artiay be disap ointed howev r, at the inco lusive i g. They may also be frustrated, as I was, by its a tic and repeti ve style and its limited and idiosynic selection among rel vant sources. fact collections, and descriptive data for all projectile points. This report is well organized and the numerous photographs, drawings, and graphs make it a valuable addition to the library of anyone interested in hunter-gatherer ecology in North America.

Two moraine sequences in one of the ice-free cirques in Topolovaya valley located above the cirque threshold at altitudes of about 700–800 m are dated by tephrochronology and lichenometry. Prominen...

An improved technique is put forward for dating rock surfaces using the sizes of lichens that grow on them. The technique has its theoretical basis in a statistical distribution model for lichen diameters. The technique differs from the conventional one in that the whole set of lichens of particular species is used in the dating. A statistical processing of the data enables one to estimate the uncertainty of age determinations and obtain results of higher accuracy than was previously possible. The use of a model for the distribution of lichen diameters allows one, in contrast to techniques that employ lichen growth curves, to determine age, not only in areas where there are objects of known age, but also over a fairly large area. This is achieved by establishing correlative relationships between the model parameters and altitude. The model parameters are determined from measurements of lichens of species Lecanora muralis (Schreb.) and Aspicilia sp. for 18 objects of known age. Specific results from applications of this version of lichenometry are the southern Tien-Shan and the Pamirs, USSR, areas that exhibit extremely active exogenous and seismic processes and which have been the key areas of lichenometric studies in the paleoseismological aspect. The ages of several earthquake-induced features have been estimated. Conclusions have been drawn about the simultaneous formation of some seismic dislocations and their association with known large earthquakes and about the recurrence of seismic events in the epicentral zones of known catastrophic earthquakes and outside these zones.

Radial growth of mature Xanthoparmelia lineola and X. subdecipiens thalli (n = 10 thalli, 170 lobes) was measured bimonthly for 2 yr at a transplant locality on the East Slope of the Colorado Front Range (altitude 2,565 m). Growth occurred during every measurement period, but was most rapid in May, June, July, and August. Ninety-three percent of seasonal growth-rate variation during the first year of the study, and 92% during the second year, are explained by differences in the duration of daytime, snow-free thallus moisture (moisture available for photosynthesis); the strength of the relationship suggests that a positive net carbon assimilation rate is translated almost immediately into lobe elongation. No negative correlation was found between radial growth and thallus moisture recorded at night or beneath snow. In the cool, continental environment of the study area, duration of photosynthetically significant thallus moisture is influenced more strongly by air temperature, day length, and snow cover than by total precipitation. At higher altitudes and latitudes, where lichenometry is used for dating, these factors will have even greater importance.

The use of lichenometry for dating neoglacial deposits in the San Juan Mountains of southwestern Colorado encounters several dif

Lichenometry and geological evidence permit establishment of a chronology of rock glacier development during Neoglaciation in the northern Sawatch Range. Portions of rock glaciers were assigned approximate absolute ages based on maximum thallus diameters of Rhizocarpon geographicum, Lecanora thomsonii, and Lecidea atrobrunnea. Values for the total percent

Results of lichenometry and rock-weathering studies on outer moraines in Skidadalur, Eyjafjordur, northern Iceland show a late Little Ice Age 19th century maximum for all glaciers except the Klaengsholl glacier. Retreat from these maximum positions occurred in three distinct phases: 1896-1908, 1915-1926, and post-1930. Evidence suggests, however, that many glaciers must have reached a position close to the Little Ice Age maximum on at least one other occasion earlier in the Neoglacial.

Measurements of Rhizocarpon geographicum thalli on rock surfaces of known age at Mount Rainier National Park permit growth curves to be constructed for andesitic and granitic substrates spanning the last 125 yr. Control points for the younger part of each curve come mainly from man-made structures, whereas older control points are from rock outcrops in the foreland of Nisqually Glacier, an area which as experienced progressive deglaciation since the early 19th century. The growth curves indicate an initial period of very rapid growth until thalli reach about 10 mm diameter, after which growth proceeds at an exponentially decreasing rate for the next century. Growth rates are slightly faster for andesitic substrates than for granite. If extrapolated, the curves should be useful for dating substrates as much as 3 to 4 centuries old with an accuracy of + 20 yr or better. However, the curves are applicable primarily between altitudes of about 1000 and 1700 m; below this zone growth rates are higher, whereas above it lichenometry may be of limited value because of widespread lichen kill during the early 19th century along the crest of the Cascade Range.

Species of Rhizocarpon subgenus Rhizocarpon are distinguished from each other based on differences in external thallus morphology, internal anatomy of fruiting bodies, and chemistry of intracellula...

Growth rates for Rhizocarpon geographicum (L.) D.C. and Rhizocarpon alpicola (Hepp.) Rabh. have been studied at different locales on the Swedish North Bothnian Coast. Shore displacement rates have been used to date maximum thallus diameters of lichens growing on cobble and boulder beaches (wave-washed moraine) at increasing elevations above mean sea level. Linear growth rates have been observed for the period ca. 200 to 1400 BP. These results, in combination with general shore chronology and radiocarbon dating, will be used for determining the ages of coastal archaeological features. Lichenometry may well prove to be an invaluable archaeological and historical tool within the Bothnian and Baltic coastal regions.

The ecological basis for using the mean of the five largest lichens in lichenometry has been examined by investigating the Rhizocarpon section Rhizocarpon species growing on gravestones in Highland...

In White River Valley and Skolai Pass in the Wrangell and St. Elias mountains of southern Alaska, several well-dated drift surfaces and abandoned alluvial channels covered with numerous lichens ser...

Dendrochronology, tephrochronology, and lichenometry, together with geological evidence establish a chronology of glacier fluctuations during Neoglaciation in the Dome Peak area. Tree-ring counts p...

In order to use lichenometry to investigate absolute as well as relative chronologies of moraines, it is necessary to establish the growth rates of the lichens used. To establish this directly in t...