Soil-site preferences for mahogany (Swietenia macrophylla King) in the Yucatan Peninsula

Although bigleaf mahogany (Swietenia macrophylla King) is one of the most important commercial timber species in the neotropics, little is known about its site preferences in the Yucatan Peninsula. We evaluated the association of mahogany with soil characteristics using the easily observed characteristics of soil color, stoniness, and relief position. The study was conducted in a commercially managed, medium-height, semi-evergreen, dry tropical forest. A total of 609 mahogany were located along 119 km of transects established in the forest. Forest site conditions were classified in 2,464, 0.78 m(2) circular plots located systematically along transects, and site conditions of mahogany along the transects were recorded for the area within 1 m radius of each tree. Mahogany preferred level sites with 93% occurring on level conditions compared to 75% for forest site plots (P < 0.001). There was also a preference for black soils (76% of mahogany versus 68% of forest site plots) and a negative preference for red soils (17% versus 27%, P < 0.001). Observed soil site preferences can improve management decisions, including where to plant mahogany and where to apply silvicultural treatments, such as liberation thinning.