|MadSci Network: Botany|
The first reference found that pines do not leach as many mineral nutrients from their leaves as do oaks and bald cypress. Therefore, Spanish moss does better in oaks and bald cypress because of the greater abundance of mineral nutrients. As an epiphyte, Spanish moss is said to do no harm to the host tree. However, epiphytes are "nutritional pirates" (Benzing 1980) that "steal" mineral nutrients that the host tree would otherwise get. The first study also noted that bark shedding and allelopathy might also influence host range of epiphytes. References Schlesinger, W.H. and P.L. Marks. 1977. Mineral Cycling and the Niche of Spanish Moss, Tillandsia usneoides L. American Journal of Botany 64: 1254-1262. Spanish Moss: Its Nature, History and Uses Benzing, D.H. (1980). Biology of the Bromeliads. Eureka, California: Mad River Press.
Try the links in the MadSci Library for more information on Botany.