Effects of the Irregular Shelterwood System on Regeneration Dynamics of Shorea robusta Gaertn. f. in Baijalpur Community Forest, Nepal

ABSTRACT The Irregular Shelterwood System (ISS) has recently been introduced in Nepalese community forests to promote sustainable regeneration of Shorea robusta (Sal). However, limited research exists on its ecological impacts and regeneration dynamics. This study examined regeneration patterns, soil properties, and environmental factors influencing S. robusta regeneration under the ISS in Baijalpur Community Forest, Kapilvastu District, Nepal. Using a stratified systematic random sampling design, data were collected from treated and untreated plots. Results showed a significantly higher density of seedlings (16,800 ha −1 ) and saplings (4693 ha −1 ) in treated plots compared to untreated areas (11,960 and 2688 ha −1 , respectively), indicating the effectiveness of ISS in enhancing regeneration. Most regeneration originated from seedlings rather than coppice shoots. Soil assessments revealed slightly acidic to neutral sandy loam soils, with higher organic matter (OM) and improved nutrient profiles in treated plots. Crown cover and organic carbon were negatively correlated with regeneration, suggesting that moderate canopy openings favor S. robusta establishment. These findings underscore the ecological importance of adaptive silvicultural practices for improving regeneration success, forest resilience, and sustainable community forestry in Nepal.