Citation: Suazo-Uribe, M.; Salvo-Sepúlveda, L.; Rosales, V.; Montero, C.; Louzada, J.L.; Branco, J.M. Assessing Treatments to Mitigate End-Face Cracking in Air-Dried Acacia dealbata Logs. Buildings 2024, 14, 2090. https://doi.org/10.3390/ buildings14072090 Academic Editors: Francesco Nocera and Alberta Latteri Received: 5 June 2024 Revised: 2 July 2024 Accepted: 3 July 2024 Published: 8 July 2024 Copyright: © 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). buildings Article Assessing Treatments to Mitigate End-Face Cracking in Air-Dried Acacia dealbata Logs Manuel Suazo-Uribe 1,2, * , Linette Salvo-Sepúlveda 3 , Víctor Rosales 2,4 , Claudio Montero 5,6 , José L. Louzada 7 and Jorge M. Branco 1 1 Department of Civil Engineering, ISISE, University of Minho, 4800-058 Guimarães, Portugal; jbranco@civil.uminho.pt 2 Department of Construction Science, Universidad del Bío-Bío, Avda. Collao 1202, Concepción 4051381, Chile; vrosaleg@ubiobio.cl 3 Department of Wood Engineering, Universidad del Bío-Bío, Avda. Collao 1202, Concepción 4051381, Chile; lsalvo@ubiobio.cl 4 National Excellence Center for the Timber Industry (CENAMAD), Pontificia Universidad Católica, Santiago 7820436, Chile 5 Laboratory of Adhesive and Composite Materials, Universidad del Bío-Bío, Avda. Collao 1202, Concepción 4051381, Chile; cmontero@ubiobio.cl 6 Laboratory of Wood Design and Technology, Universidad del Bío-Bío, Avda. Collao 1202, Concepción 4051381, Chile 7 CITAB, Departamento Florestal, University of Trás-os-Montes and Alto Douro, Quinta de Prados, 5000-801 Vila Real, Portugal; jlousada@utad.pt * Correspondence: msuazo@ubiobio.cl Abstract: Acacia dealbata Link, known as Mimosa in Portugal, is an invasive hardwood species with potential for construction use, but research is limited. The available stock of small-diameter juvenile wood logs can help reduce this gap, but tangential cracking at log ends challenges fastener connections. This study evaluated different treatments to control and reduce end-face cracking in small wood logs during air drying, an economical and environmentally friendly procedure. The extreme two-thirds of sixteen Mimosa logs were subjected to two treatments: one with longitudinal kerfs 15 mm deep along the length (two and three kerfs) and the other with a hollow in the center up to half the length (16 mm and 30 mm diameters). Over 219 days of air drying and compared with the central part, kerfing treatments significantly reduced outer-wood tangential cracking (p < 0.001), with the three kerfs also reducing crack numbers (p < 0.05) but increasing significantly cracks near the pith (p < 0.01). The 30 mm central hollow significantly reduced central perforation cracking (p < 0.05). Prospectively, the results suggest that a combined treatment approach involving cross-cuts could help reduce and/or control end cracking, thereby improving the suitability of wild Mimosa logs for construction use. Keywords: invasive hardwood control; log end cracking; small juvenile wood logs 1. Introduction Acacia dealbata Link, commonly known as Mimosa in Portugal, is a hardwood species native to Australia. It is highly invasive due to its rapid growth rate and prolific seed production [1], significantly increasing fuel loads in colonized native forests [2,3]. Accord- ing to the national forest inventory [4], the area covered by species of the Acacia genus, unlike other forest species, such as Pinus pinaster Link, increased by 3.7 ha between 1995 and 2005 and now occupies 8.4 thousand ha in continental Portugal. A control method involves harvesting, resulting in a residual reserve of Mimosa. Some authors indicate that using these residues helps reduce the high costs of controlling invasive species [5]. Additionally, it would support the integration of these by-products into a circular economy Buildings 2024, 14, 2090. https://doi.org/10.3390/buildings14072090 https://www.mdpi.com/journal/buildings