The Giant Sequoia played several crucial roles in the founding of the modern science of tree-ring dating. These included at least two central theoretical constructs and at least two minor ones; however, historical studies of dendrochronology are actively continuing and this list is expected to expand. Second only to the importance of the ponderosa pine (Pinus ponderosa) in the earliest days of the infant science, the Giant Sequoia (Sequoiadendron giganteum) was at the very center of the establishment of the discipline of dendrochronology. How the sequoia came to be used by A.E. Douglass, and what vital information and how it provided such information is the topic here.

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Increment cores that dry with a spiral twist are a problem in any study where a clear view of transverse wood anatomy is required. This problem may become acute when working with wood that is partially decomposed. After soaking cores in a urea solution, we can remove spiral twists by applying steam to the cores and gently twisting cores until they straighten. Treatment does not result in a serious distortion of ring widths.

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Since the mid-1700s, slash (Pinus elliottii Engelm.) and longleaf (Pinus palustris Mill.) pines growing in the coastal plain region of the southeastern United States were intentionally wounded ("boxed" and/or "chipped ") to induce the production of resin, which was then collected and distilled into turpentine and its derivatives (termed "gum naval stores "). Relicts from this once-dominant industry are seen throughout southern pine forests as boxed and chipped stumps or (rarely) still living trees. In this study, we dated the years of chipping on slash pines growing in two locations in Lowndes County, Georgia, to (1) better understand past forest land use patterns, and (2) raise public awareness of the ethnohistorical importance of these trees to the cultural heritage of southern Georgia. We collected cores from ten living trees with characteristic chipped surfaces ("catfaces ") from Taylor-Cowart Memorial Park (TCMP) in Valdosta, Georgia, and cross sections from ten chipped stumps in the area surrounding Lake Louise, 12 km south of Valdosta. We conclude that chipping at TCMP occurred in 1947-1948, while two chipping events occurred at Lake Louise around 1925 and between 1954-1956. Our dating was facilitated by observing periods of growth suppression, distorted and /or discolored rings, and the absence of some growth rings that may indicate possible chipping events. We recommend that these chipped stumps and living trees be preserved intact for their ethnohistorical significance, educational importance, and potential for future research.

Six mean ring-width tree-ring chronologies were constructed for living Scots pine (Pious sylvestris L.), growing near the species' upper and northern limits in the area between the Ob River and the subpolar Ural Mountains in Russia. All ring-width series were standardized by fitting cubic smoothing splines and chronologies were constructed as biweight robust means. The six chronologies ranged from 181 to 276 years in length. Response function analysis showed all chronologies to have negative responses to winter precipitation. Most chronologies also showed positive, but relatively low responses to temperatures of the current and previous summer. Total October-May precipitation was reconstructed back to A.D. 1843 using the lagged and unlagged chronologies as candidate predictors. In addition to reflecting an unstable and time-varying growth-climate link, moderate verification results may partly be due to problems with short verification periods. The reconstruction contains almost equal amounts of high-frequency (<8 years) and low-frequency ( >8 years) variations, among them a significant 30-year variation. The precipitation signal may add an important aspect to reconstructing paleoclimatic fluctuations in the northern hemisphere. Continuing work with the Scots pine from this area depends on improving the quality of a precipitation reconstruction and finding older living and subfossil wood.

A 155-point US grid of tree-ring reconstructed summer (JJA; Cook et al. 1996) averaged Palmer Drought Severity Index (PDSI) was used to document the history and investigate the external forcing of growingseason climate anomalies for the period 1700 to 1978. Statistical analysis software was used to composite years temporally by computing averages for the years of known dates of major potential climate-forcing events. A geographic information system (GIS) was used to display the composites as well as individual years. The forcing factors investigated were the 22-year Hale solar magnetic cycle, major El Niño (warm) and La Niña (cold) events based on the Southern Oscillation Index (SOI), and large magnitude low latitude volcanic eruptions. Positive and negative moisture anomalies appear around Iowa in the alternate 11-year sunspot cycles that make up the Hale solar magnetic cycle. Experimentation with the grouping of years in the Hale cycle composites led to unexplained spatial shifts of the moisture anomalies in the same region. The El Niño episodes usually show positive (wet) PDSI anomalies in the Southwest from California to Texas, while La Niña events usually have drought in the same area, with some inconsistent signals in the north central Plains and the Northwest. The eastern and northern US were unaffected by the Southern Oscillation, although the summer season reconstructed PDSI may have missed the SOI variation, which is primarily a winter signal. The three largest tropical volcanic eruptions since 1800 failed to follow a consistent pattern, but the 1815 eruption of Tambora in Indonesia was followed by a very strong positive growth anomaly in the Southwest in 1816 and 1817. Important regional studies with the winter-spring season could be done with this network of tree-ring chronologies and observed monthly PDSI data.

As a long master tree -ring chronology for the region around the Aegean approaches completion, timbers from monuments and archaeological sites as far as 2,000 km apart, and as far back as 7000 BC, are being dated. The patterns used in this dating are characterized by signature years, in which trees at the majority of the sites have smaller or broader rings than in the previous year. We show that the signature years are consistently associated with specific, persistent, circulation anomalies that control the access of precipitation- bearing systems to the region in springtime. This explains the feasibility of dating wooden objects from widely dispersed sites, and opens the possibility of reconstructing aspects of the climate in which the wood grew.

Archaeological tree-ring samples provide environmental, chronological, and behavioral information about past human use of the landscape. Such information, however, can only be fully exploited if sample pro- veniences and beam attributes are completely documented. This paper discusses implications of the sample proveniences, beam attributes, and dates from McKean Pueblito, an eighteenth century Navajo site in northwestern New Mexico, USA. Although the date distribution suggests at least three different interpretations of the site construction history, the contextual data indicate that the site was built in AD 1708 and remodeled in 1713. Areal contextual and tree-ring data from McKean Pueblito and other sites in the area are used to discuss larger scale Navajo behavioral and demographic adaptations to the changing physical and social environments of eighteenth century New Mexico. These examples illustrate how sample context at various spatial scales can significantly enhance interpretations of tree-ring data.

Many studies use the temporal record of dendrochronologically-dated fire scars to document properties of fire regimes before human interference (e.g. fire suppression, logging, and agriculture) became pervasive. Such reconstructions provide vital information that can be used by land management agencies when designing and implementing fire management policies, and are especially useful for justifying the reintroduction of fire to areas where fire has long been excluded by humans. Tree-ring based fire history studies produce large quantities of data that require efficient tools for compilation, organization, and analysis. In this paper, I describe the development and use of FHX2, software comprised of individual modules designed specifically for (1) entering and archiving of fire history data, (2) creating graphs that display both temporal and spatial features of the site fire history, (3) conducting statistical analyses on fire intervals and seasonality, and (4) performing superposed epoch analysis to analyze climate /wildfire interactions. Although designed to analyze fire history, the software can be used to analyze any set of events recorded in the tree- ring record, such as growth suppressions and releases, floods, and insect outbreaks.