In this lab, the relationship between Spanish moss (Tillandsia usneoides) and one of its host species, the Southern live oak (Quercus virginia) was observed on a portion of the University of Florida campus in Gainesville, FL. Spanish moss is an atmospheric epiphyte and the Southern live oak is a hardwood tree. Some possible interactions between the two species were neutralism, commensalisms, mutualism, and parasitism. It was hypothesized that the relationship would be commensalism, with Spanish moss benefited and the Southern live oak neither benefited nor harmed. The type of symbiotic relationship was determined using two factors, the relative health of the host oak tree and its relative load of Spanish moss. A two-way X2 test for independence was performed using the data recorded. Calculations gave a X2 value of 0.61 and p-value between 0.1 and 0.5, with one degree of freedom and the level of significance, α, equal to 0.05. Since the p-value was greater than the α value, the lab observations failed to reject Ho, and the conclusion was that the data supported no interaction between Spanish moss and the Southern live oak. Therefore, the lab observations did not support the hypothesis of commensalism between the two species.
Introduction In this lab, the interaction between the two species Spanish moss (Tillandsia usneoides) and the Southern Live Oak (Quercus virginiana) were observed and the type of relationship was determined using field observations of live oaks with Spanish moss on them and recording the relative load of Spanish moss and the relative health of each tree observed. This is important in order to study the effects of epiphytes on host plants, and the possible environmental implications that such relationships would have, such as whether or not the Spanish moss is harming the oak trees. This study could be helpful to serve as a basis for other epiphyte and host interaction studies, particularly for endangered plants
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