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-Total ring, earlywood, and latewood master chronologies were derived for six stands (three of each of the two varieties) of sand pine (Pinus clausa) spanning the geographic breadth of the species extant range in Florida, USA. Climate/growth correlations, analysis of extreme growth years, and multiple regression models were developed to relate growing season (current and lagged) monthly temperature and precipitation with interannual variability in sand pine growth increments. Four research hypotheses were evaluated: (1) Sand pine growth is more sensitive to variation in precipitation than variation in temperature. (2) Sand pine growth variation is linked to El Niño-Southern Oscillation warm-vs. cold-phase events. (3) Climate/growth relations are stronger for the peninsular (Ocala; P. c. var. clausa) variety of sand pine than the panhandle (Choctawhatchee; P. c. var. immuginata) variety. (4) Climatic signals are stronger for coastal populations (vs. inland) for both varieties. Precipitation (especially in the winter/spring season of current-year growth) was more strongly linked to sand pine growth than temperature, earlywood growth was significantly greater in warm-phase El Niño-Southern Oscillation years in four of the six stands, and climate/growth relationships were stronger in coastal populations. We found no consistent inter-varietal contrasts in the strength of climatic signals, although climate/growth relationships were distinctive in the two inland panhandle stands, where canopy/understory interactions may partially obscure expression of climatic influence. We found greater sensitivity to temperature in inland panhandle stands (especially in latewood series), but consistently strong growth response to precipitation in the other four stands (especially in earlywood and total ring series). Our findings extend the evidence for ENSO influence on terrestrial biophysical phenomena in Florida.sand pine / dendroclimatology / El Niño-Southern Oscillation / Florida Résumé -Effets de la variabilité climatique sur la croissance radiale de deux variétés de pin (Pinus clausa) en Floride, USA. La chronologie des années caractéristiques a été dérivée de la mesure des cernes, du bois initial et du bois final dans 6 peuplements (3 pour chacune des variétés) de Pinus clausa représentant toute la gamme géographique de l'espèce en Floride, USA. La corrélation climat/croissance, l'analyse des années de croissance extrême et des modèles de régression multiple ont été développées pour établir les relations entre la température et les précipitations mensuelles au cours de la saison de végétation, et la variabilité inter-annuelle des accroissements de Pinus clausa. Quatre hypothèses de recherches ont été évaluées : (1) La croissance de Pinus clausa est plus sensible aux variations des précipitations qu'à celles de la température. populations côtières (versus intérieures) pour les deux variétés. Les précipitations (particulièrement celles de la saison hiver-printemps de l'année courante de croissance) sont plus fortement l...

This paper presents a system for detection of some important internal log defects via analysis of axial CT images. Two major procedures are used: the first is the segmentation of a single computer tomography (CT) image slice which extracts defect-like regions from the image slice, the second is correlation analysis of the defect-like regions across CT image slices. The segmentation algorithm for a single CT image is basically a complex form of multiple thresholding that exploits both the prior knowledge of wood structure and gray value characteristics of the image. The defect-like region extraction algorithm first locates the pith, groups the pixels in the segmented image on the basis of their connectivity and class$es each region as either a defectlike region or a defect--ee region using shape, orientation and morphological features. Each defect-like region is classified as a defect or non-defect via correlation analysis across corresponding defect-like regions in neighboring CT image slices.