Anomalies in tree-rings of stone pine (Pinus pinea L.) and Aleppo pine (Pinus halepensis Mill.) from Guardamar del Segura in SE Spain were researched. We took discs of wood from different heights in the stems of 6 trees (3 trees of each species), smoothed them, and on each section along 8 radii analysed and dated tree-rings. TSAP and ARSTAN programme were used for analyses. The number of discontinuous tree-rings was higher than the number of missing rings. The number of missing rings was higher in Aleppo pine than in stone pine. Calculated SSS (sub sample signal strength) showed that it is enough to measure tree-ring widths along one or two radii at breast height of a tree if we can date the tree-rings correctly. Comparison between ARSTAN residual chronologies of researched trees with reference chronologies of stone pine and Aleppo pine from the same site confirmed that we correctly dated normal, missing and discontinuous rings. The tree-ring width series with located discontinuous or missing rings proved to be equally useful to study the response of trees to climate as the tree-ring series without such anomalies. In the trees where we expect high level of missing rings we recommend to increase number of sampled trees or to take samples of wood at several heights in the stem of the same tree. Due to particular characteristics of trees from different sites, we can not suggest any common guidelines for necessary number of cores (samples) of wood for dendrochronological analyses.
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