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Thinning focused on achieving growth and diameter management objectives has typically led to stands with reduced climate sensitivity compared to unthinned stands. We integrated dendrochronological with Airborne Laser Scanner (LiDAR) data and growth models to assess the long-term impact of thinning intensity on Canary pine (Pinus canariensis) radial growth. In 1988, 18 permanent treatment units were established in 73-year-old Canary pine plantations and three thinning treatments were applied (C–control-unthinned; 0% basal area removal; MT–moderate thinning: 10% and 15% basal area removal, and HT–heavy thinning: 46% and 45% basal area removal on the windward and leeward slopes, respectively). Dendrochronological data were measured in 2022 and expressed as basal area increment (BAI). The impact of climate on growth was examined by fitting linear regression models considering two different Representative Concentration Pathway (RCP) climate scenarios, RCP 2.6 and RCP 4.5. Finally, LiDAR data were used for standing segmentation to evaluate changes in overall growth under different climatic scenarios. The LiDAR–stand attributes differed between aspects. The BAI of the most recent 20 years (BAI20) after thinning was significantly higher for the moderate and heavy treatments on the leeward plots (F = 47.31, p < 0.001). On the windward plots, BAI decreased after moderate thinning. Considerable thinning treatments resulted in stronger changes in growth when compared to RCP climatic scenarios. From a silviculture perspective, the mapping of canopy structure and growth response to thinning under different climatic scenarios provides managers with opportunities to conduct thinning strategies for forest adaptation. Combining dendrochronological and LiDAR data at a landscape scale substantially improves the value of the separate datasets as forecasted growth response maps allow improving thinning management plans. [ABSTRACT FROM AUTHOR]

Canary Island pine (Pinus canariensis C.Sm. ex DC) is a species endemic to the Canary Islands (Spain) that was for centuries overexploited for its wood and resin. Due to the state of the pine forest, more than 10,000 hectares were reforested in the middle of the 20th century. Now, under the silvicultural management plan, thinning operations have allowed Canary Island pine wood to be mechanically characterised for the first time using large test pieces. In total, 1529 pieces measuring 2600 × 120 × 35 mm and visually graded according to Spanish standard UNE 56544 (Visual grading of large structural coniferous sawn timber) were assessed, resulting in 872 pieces in grades ME-1 and ME-2 and 657 rejects. After the characteristic values of density (479–453 kg∙m−3), modulus of elasticity (MOE) (14,023–11,276 N∙mm−2) and bending strength (MOR) (26–14 N∙mm−2) were determined for both grades (ME-1 and ME-2), strength class C24 was assigned to grade ME-1, with similar values to Pinus radiata D.Don and Pinus pinaster Aiton, and C14 was assigned to grade ME-2. Density, number of growth rings, growth ring width, and presence/absence of resinous wood have a significant influence on MOE and MOR, for a confidence level of 95%. Reforestation of Canary Island pine not only allows restoration of the forest cover, but also provides an opportunity, through thinning, to obtain quality wood, helping to create employment and associated industry. This local example with an endemic species can be extrapolated to other parts of the world. [ABSTRACT FROM AUTHOR]