New York State (NYS) has a long and significant history of tree-ring research. Some of the earliest dendroarchaeological and dendroclimatic work in eastern North America was done in NYS, and 1970s studies in Hudson Valley in the east of the state were important for demonstrating that drought records could be reconstructed from trees growing in humid environments. Some recent work in NYS is described in this issue of Tree-Ring Research, including tree-ring dating and provenancing of a boat in New York City, dendroarchaeological studies in a town in northeastern NYS, dendrogeomorphological work in central NYS, and a dendroclimatic investigation of two range-margin Juniperus species growing on alvars. The last of the five NYS papers in this issue provides a personal historical perspective on the beginnings of drought reconstructions in the Hudson Valley. There is considerable potential for future work in New York with extension of existing studies and work in new areas and with new tree species.

On July 2010, archaeologists monitoring excavation at the World Trade Center site (WTC) in Lower Manhattan found the remains of a portion of a ship's hull. Because the date of construction and origin of the timbers were unknown, samples from different parts of the ship were taken for dendrochronological dating and provenancing. After developing a 280-year long floating chronology from 19 samples of the white oak group (Quercus section Leucobalanus), we used 21 oak chronologies from the eastern United States to evaluate absolute dating and provenance. Our results showed the highest agreement between the WTC ship chronology and two chronologies from Philadelphia (r  =  0.36; t  =  6.4; p < 0.001; n  =  280) and eastern Pennsylvania (r  =  0.35; t  =  6.3; p < 0.001; n  =  280). The last ring dates of the seven best-preserved samples suggest trees for the ship were felled in 1773 CE or soon after. Our analyses suggest that all the oak timbers used to build the ship most likely originated from the same location within the Philadelphia region, which supports the hypothesis independently drawn from idiosyncratic aspects of the vessel's construction, that the ship was the product of a small shipyard. Few late-18^th Century ships have been found and there is little historical documentation of how vessels of this period were constructed. Therefore, the ship's construction date of 1773 is important in confirming that the hull encountered at the World Trade Center represents a rare and valuable piece of American shipbuilding history.

Historical timbers have been sampled from buildings at 13 sites in Willsboro, New York, on the west shore of Lake Champlain. Ring-width series from 139 timbers have been successfully crossdated and used to develop tree-ring chronologies for ash (Fraxinus spp.), oak (Quercus spp.), pine (Pinus spp.), eastern hemlock (Tsuga canadensis (L.) Carr.), and spruce (Picea spp.), which collectively span A.D. 1555 to 1878. Tree cutting dates suggest that Windyview Manor was likely built in or soon after 1799, and a barn and farmhouse at the 1812 Homestead were built in or soon after 1812 and 1813, respectively. These dates are all consistent with documentary records for these sites. Aggregate data for the town suggest a shift in wood use for building during the 19^th Century, with ash and oak commonly used for large frame timbers from the 1790s to 1820s, and hemlock and spruce dominating from the 1830s to 1860s. Chronologies developed in this project are among the first from historical timbers for northern New York and will facilitate further dendroarchaeological work in the region.

This report summarizes the results of three case studies where dendrochronology was used to evaluate hydrologic and geomorphic change in parts of Tully Valley, in central New York, over the past 150 years. The case studies evaluate 1) the changes in water quantity and quality in a wetland area several miles north of an area of former solution-brine mining, 2) the development of recent bedrock fractures above former solution brine-mining areas, and 3) the development and timing of landslide movement. The advantage of contemporary dendrochronology is that tree-ring analysis can provide a background of hydrologic and geomorphic change when no direct documentation or data are available.

The long generation time of woody plants inhibits detection of shifts in their distributions induced by climatic change. Consequently, assessing growth changes within existing populations, especially those near species range margins, can increase understanding of climate change impacts. We apply dendrochronological methods to examine recent radial growth of the ecologically similar species Juniperus communis L. and J. virginiana L. growing under the same conditions but at opposite latitudinal range margins. We use moving correlations to analyze changes in relationships between growth and monthly climatic variables, and regional curve standardization to identify trends in growth rate independent of plant age. For J. communis, growth sensitivity to temperature and precipitation shifted earlier in the spring whereas for J. virginiana only temperature sensitivity shifted earlier over the last 50 years. Since 1920, J. virginiana growth displays an upward trend, but J. communis growth shows both increases and decreases. Recent precipitation increase, rather than warming alone, appears to drive the growth trends, but interactions with temperature and vegetation dynamics, instead of range position, likely account for the differences in trends between species. Although these results generally agree with climate change predictions, they also point out potential difficulties in modeling future species ranges based on growth-climate relationships and growth at range margins.

A brief and personal history of the development of dendrochronology in the Hudson Valley of New York in the 1970s and the quantitative reconstruction of climate from tree rings there is provided. Two people stand out in allowing that to happen. Marvin Stokes at the Laboratory of Tree-Ring Research sparked within me a deep and enduring interest in dendrochronology, and Daniel Smiley of Mohonk supported my interest in pursuing tree-ring research in the Shawangunk Mountains through his deep and curious love of its natural environment. The discovery of ancient trees growing in the Shawangunk Mountains, and their use in successfully reconstructing past drought there, truly launched my career as a dendroclimatologist and proved beyond doubt that dendroclimatology and the reconstruction of past climate could be successfully conducted in the northeastern United States.

This study focuses on tropical tree growth rates in Western Kenya. The dendrochronological potential of each study species was determined by visual examination of rings, and then cumulative growth trajectories for diameter were synthesized for species of sufficient sample size (n ≥ 3), based on ring-width chronologies. The 14 tree species considered were: Acacia mearnsii, Bridelia micrantha, Combretum molle, Croton macrostachyus, Cupressus lustianica, Eucalyptus camaldulensis, Eucalyptus grandis, Eucalyptus saligna, Grevillea robusta, Mangifera indica, Markhamia lutea, Persia Americana, Syzygium cumini, and Trilepisium madagascariensis. The species with the highest dendrochronological potential included Acacia mearnsii, Cupressus lusitanica, the Eucalyptus spp. and Mangifera indica, which are all non-native species that successfully crossdated. The results also indicated that the species with highest dendrochronological potential had strong radial growth synchrony, which was reflected in high inter-tree correlation and (or) high growth variance explained by the first principal component axis. Furthermore, A. mearnsii and E. camaldulensis were sensitive to annual precipitation and moisture index. The species with the lowest dendrochronological potential were Grevillea robusta and Markhamia lutea. In terms of productivity, the three fastest growing species in the study, based on annual diameter increment, were Eucalyptus camaldulensis, Eucalyptus grandis, and Acacia mearnsii. This study also has great potential to extrapolate historical patterns of diameter growth to understanding annual aboveground biomass and carbon dynamics in Western Kenya.

Longitudinal variations in select wood quality parameters were examined in 26-year-old loblolly pine trees planted in Anhui Province, China. Wood density and ring width were measured from cross-sections of different heights of merchantable stems. The average ring width decreased from the base to 1.3 m, then increased to the maximum at 7.6 m, and thereafter reduced with stem height. The longitudinal patterns varied with cambial age in ring width. The coefficient of variation in ring widths along the stem height was greater than 21% at the cambial age 5–8 years and 9–12 years, and small variations were observed in other cambial age groups. The average wood density declined from 1.3 m to 7.6 m and then slightly increased with increasing stem height. The wood density showed great variation at different growth stages below 7.6 m, but varied less above 7.6 m. Basal area increment (BAI) gradually increased with increasing ring number (from the pith to the bark) at different stem heights, and markedly reduced after the 22^nd ring. These results indicate that the longitudinal variations of wood density, ring width and BAI in loblolly pine are greatly affected by cambial age. The detailed information of the wood properties along stem heights could be useful to wood utilization of loblolly pine.

To assess if tree age may modulate the main climatic drivers of radial growth, two relict Pinus nigra subsp. salzmannii populations (María, most xeric site; Mágina, least xeric site) were sampled in southern Spain near the limits of the species range. Tree-ring width residual chronologies for two age groups (mature trees, age ≤ 100 years (minimum 40 years); old trees, age > 100 years) were built to evaluate their responses to climate by relating them to monthly precipitation and temperature and a drought index (DRI) using correlation and response functions. We found that drought is the main driver of growth of relict P. nigra populations, but differences between sites and age classes were also observed. First, growth in the most xeric site depends on the drought severity during the previous autumn and the spring of the year of tree-ring formation, whereas in the relatively more mesic site growth is mainly enhanced by warm and wet conditions in spring. Second, growth of mature trees responded more to drought severity than that of old trees. Our findings indicate that drought severity will mainly affect growth of relict P. nigra populations dominated by mature trees in xeric sites. This conclusion may also apply to similar mountain Mediterranean conifer relicts.

A lightweight, portable device for extracting stuck or broken increment borers is presented and its operation described. The “Decorum” extractor is compact and weighs less than 400 g. It is easily carried in a belt pouch or pocket and is both reliable and easy to operate. The extractor does not require fixed tie points nor does it damage the tree. It offers an effective solution to a widely occurring problem in dendrochronology and forest research.