The longest tree-ring chronologies for the Southern Hemisphere published to date go back to A.D. 1011 in central Chile; 1028 in Tasmania, Australia; 1140 in western Argentina; and 1256 on the North Island, New Zealand. For paleoclimatic and other studies longer time series would be very desirable. Here we report on the first successful crossdating and chronology development for Fitzroya cupressoides, a redwood-like conifer in western Argentina, which goes back to 441 and exhibits desirable statistical characteristics.

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The Midlands and South-west of England are represented by a long oak tree-ring chronology spanning approximately 4500-3900 BC (calibrated radiocarbon dates). The wood on which it is based originates in a technologically advanced trackway crossing the low-lying Somerset Levels, in a coastal submerged forest probably killed by rising sea-level, and in flood-plain oaks washed down the River Trent. Cross-matching between the growth patterns of the three groups of trees is of good quality, yet so far the chronology has failed to cross-date with the long Irish and German dated chronologies. The reasons for this, and the implications of eventual dating, are discussed.

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Tree-ring samples were collected from six coniferous species in the western Himalayan ranges during the summer of 1984 in order to evaluate their potential for use in dendroclimatic reconstructions. Picea, Abies, and Pinus spp. had previously been collected for ring widths and densitometric analysis by Hughes and co-workers on relatively mesic subalpine sites near the Vale of Kashmir. Our results support this earlier work in that ring-width series from these habitats are relatively complacent and contain little dendroclimatic information. Density and ring widths are largely temperature-dependent. However, our sampling included Cedrus deodara and Pinus gerardiana from lower altitudes in the dry inner valleys of the Pir Panjal Range, south of Kashmir. Both species exhibit great age, high mean sensitivity and good intra- and inter-specific crossdating, and yielded chronology statistics suggestive of a drought response. We strongly recommend that they receive high priority in future tree-ring research in northwest India.

The first dendrochronolcgical investigation in the USSR was carried out at the end of the past century. Systematic study of tree rings for the purpose of dating different events and reconstruction of natural conditions began in 1950-1960's. Tree-ring analysis is most intensively used in the studies of forest ecosystem dynamics, timing and frequency assessment of catastrophic phenomena, reconstruction of radiocarbon content in the Earth atmosphere, and dating of historical wood. Much attention is given to the development of long-term prognoses of tree growth and forest environments.

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Two modem tree-ring width chronologies of Pinus sylvestris L. have been established in an area near the southern limit of the species' distribution. Trees were sampled in the South of Catalonia in northeastern Spain where Mediterranean climatic conditions are of primary influence. To better understand climate ring-width relationships, tree-ring index series have been studied in relation to local climate. Ring-widths are strongly related to low precipitation at the beginning of the growing season in March, in June of the current growth year, and in September prior to tree-ring growth. High temperatures mainly affect growth in summer during the growing season and in autumn of the year prior to growth. During the winter, mainly in December, mean monthly temperatures show a significant positive correlation with growth. Major factors controlling the southern distribution of P. sylvestris may be related not only to water stress in summer but also to the amount of precipitation at the beginning of the growing season and in autumn, even in mild winters.

Thirty-one old-age pine stands in nine mountainous regions of Spain were studied in order to delineate dendrochronologically uniform areas. A country-wide cross-correlation analysis of the autoregressively standardized site chronologies showed the dendrochronological signal decreasing with distance so that beyond about 450 km crossdating becomes less reliable, but even over 630 km, the correlation coefficient is sometimes significantly high. A principal components analysis of the variance among the site chronologies segregated the chronologies into a northern and a southern group roughly along a line from Madrid to Barcelona. Two low-elevation northern sites were grouped with the southern sites. Moisture supply limits the growth of the pines in this group. In contrast, the high-elevation northern sites do not suffer from prolonged droughts. According to the uniform and extensive tree-ring signal in the south of the peninsula, the potential of dendrochronology for dating cultural objects is predicted to be favorable. Because of the greater variability between sites in the north, further studies are necessary to delineate uniform areas.

Twenty-three Libocedrus bidwillii (New Zealand cedar) tree-ring chronologies have been developed from New Zealand. This total consists of twelve new sites collected by the authors and eleven previously collected by others (five of which we have updated and six of which were not). Standardization of the tree-ring series from each site used a double detrending method (linear-exponential or linear regression or a horizontal detrending plus spline detrending fitted to 2/3 the length of each tree-ring series). ARSTAN modeling using the Aikaike Information Criterion (AIC) to determine the filter model removed all significant autocorrelations from the residual chronologies. The average chronology length is around 500 years, and the sites are spread over 8° of latitude (i.e.. 38°-46 °S) and nearly 10(X) m in elevation (i.e., 244-1220 m.a.s.1.). The species tends to grow slowly (mean ring-width 0.7 mm), and the tree rings have a high autocorrelation value (0.79). The average mean sensitivity was 0.17, and the average mean correlation between all radii within chronologies was 0.55. Comparison of the chronologies showed a highly consistent and significant pattern among most of the sites. There was a reduction in interchronology correlation with separation distance; however, there was no clear relationship, or an effect, due to elevation. The spatial extent and temporal length of the network of sites offers the most comprehensive opportunity for New Zealand climate reconstruction to date.