In addition to the direct erosion effect the
Most of the hillslopes of the park are covered by forests mainly formed of P. canariensis, a Canary palaeoendemic AG-1478 that grows in well preserved forests on this island ( Arévalo and Fernández-Palacios, 2009). The forests extend up to 1800 m asl., and sometimes include willows (Salix canariensis) at the edges of ravines. Willows are generally related to the river bed and develop short-lived trunks that can be translocated and dragged with flood events ( Fig. 3). In contrast, pines are able to survive low-to-moderate damage, producing characteristic growth patterns that allow tree ring dating of such disturbances. P. canariensis has unique characteristics among pines that are generally linked to the volcanic environments where it currently lives ( Navascués et al., 2006). These include its colossal size, thick bark, resprouting ability, a characteristic heartwood, powerful taproot and high longevity ( Climent et al., 2004, Esteban et al., 2005 and Genova and Santana, 2006). These life-history traits make this species appropriate for tree ring studies to reconstruct geomorphic events by using dendrogeomorphological evidence ( Díez-Herrero et al., 2013b).