Juniperus thurifera allometry data across a natural expansion gradient in Alto Tajo, Spain

This data was collected as part of the SPONFOREST project in 2017 in the Alto Tajo region of Spain. Field data on tree characteristics and properties were collected across a successional gradient Juniperus thurifera trees across two field sites (Ribarredonda and Huertahernando), 447 trees and 10 plots and three successional stages. Each tree was georeferenced using a differential geographic positioning system, and surveyed for height, stem diameter at breast height (used to calculate tree quadratic diameter, QD), basal area, sex, and crown diameter (average of two perpendicular measurements) between June and October 2017.Each row of data corresponds to a stem of a tree within one of the plots. All stems with a diameter at brest height of over 3cm were recorded. Allometric data collected include quadratic mean diameter of stems, tree basal areal, tree height, stem number, stem diameter at breast height, crown projection diameter, tree sex, location and the age of the first tree ring. The age of first tree ring was measured on 30 trees per plot by extracting wood cores and counting and measuring tree ring widths. see Alfaro-Sánchez et al. 2021a; 2021b for methodological details on tree age and dataset. This research was funded by the Natural Environment Research Council (NERC), the Spanish Ministry of Economy and Competitiveness (MINECO) grant: 345 SPONFOREST (BiodivERsA3-2015-58, PCIN-2016-055), COMEDIAS (CGL2017-83170-R) and Comunidad de Madrid grant: REMEDINAL TE (Ref. TE-CM. S2018/EMT-4338, 347 2019-2023-Comunidad de Madrid). A.F. was supported by a JAE-predoc fellowship from the Spanish National Research Council (CSIC) and later by an APOSTD fellowship from the Generalitat Valenciana and co-funded by the European Union. For further information please contact Alicia Forner or Laura Bentley. Alfaro-Sánchez, R., J. M. Espelta, F. Valladares, B. Acuña-Míguez, and I. Martín-Forés. 2021a. “Disentangling the role of sex dimorphism and forest structure as drivers of growth and wood density in expanding Juniperus thurifera L. woodlands.” Annals of Forest Science 78(4): 1-19. https://doi.org/10.1007/s13595-021-01097-6 Alfaro-Sánchez, R., A. S. Jump, J. Pino, O. Díez-Nogales, and J. M. Espelta. 2019. “Land use legacies drive higher growth, lower wood density and enhanced climatic sensitivity in recently established forests.” Agricultural and Forest Meteorology 276–277: 107630. https://doi.org/10.1016/j.agrformet.2019.107630