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Soil properties and forest productivity can be affected during ground-based harvest operations and site preparation. The degree of impact varies widely depending on topographic features and soil properties. Forest managers who understand site-specific limits to ground-based harvesting can alter harvest method or season to limit soil disturbance. To determine the potential areal extent of detrimental (potentially plant growth limiting) soil disturbance based on site characteristics and season of harvest, we developed a predictive model based on soil monitoring data collected from 167 groundbased harvest units. Data collected included dominant site parameters (e.g., slope, aspect, soil texture, and landtype), harvest season, harvest type (intermediate or regeneration), and the machine(s) used during ground-based harvest operations. Aspect (p = 0.0217), slope (p = 0.0738), landtype (p = 0.0002), and the interaction of harvest season × landtype (p = 0.0002) were the key variables controlling the areal extent and magnitude of detrimental soil disturbance. For example, harvesting during non-winter months on gently rolling topography resulted in greater soil disturbance than similar harvest operations on landscapes that are highly dissected. This is likely due to the ease with which equipment can move off designated trails. A geospatially explicit predictive model was developed using general linear model variables found to significantly influence the areal extent of detrimental soil disturbance on nine defined landtypes. This tool provides a framework that, with local calibration, can be used on other forest lands as a decision support tool to geospatially depict landtypes susceptible to detrimental soil disturbance during ground-based harvest operations.Résumé : Les opérations de récolte et de préparation de terrain qui se déroulent sur le terrain peuvent avoir un impact sur les propriétés du sol et la productivité de la forêt. L'ampleur de l'impact varie énormément selon les caractéristiques topographiques et les propriétés du sol. Les aménagistes qui comprennent les limites inhérentes à chaque station pour la récolte sur le terrain peuvent modifier les méthodes de coupes ou la saison de récolte afin de minimiser la perturbation du sol. Pour déterminer l'étendue aréale potentielle des perturbations néfastes (qui peuvent limiter la croissance des plantes) du sol selon les caractéristiques de la station et la saison de récolte, nous avons élaboré un modèle de prédiction basé sur des données de suivi du sol collectées dans 167 unités de récolte sur le terrain. Les données qui ont été recueillies incluaient les principaux paramètres de la station (p. ex. pente, exposition, texture du sol et type de sol), la saison de récolte, le type de coupe (intermédiaire ou de régénération) et la machinerie utilisée lors des opérations de récolte sur le terrain. L'exposition (p = 0,0217), la pente (p = 0,0738), le type de sol (p = 0,0002) et l'interaction entre la saison de récolte et le type de sol (p = 0,0002) étaient les principales...

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