This paper will explore the influence shoot specific endophytic fungi have on rhizosphere biogeochemical processes by examining the well characterized association between the shoot specific enodphytic fungus Neotyphodium coenophialum and its host Festuca arundinacea (tall fescue;TF). It has long been recognized that the association between these symbiotic partners has imparted distinct advantages to the host plant including tolerance to drought, heat, low soil fertility, heavy metals and herbivore feeding. Chief among these advantages is the anti-herbivore ability from the fungal production of toxic alkaloids resulting, most notably, in the observed animal nutrition issues (fescue toxicosis) in livestock grazing on tall fescue pastures. In an attempt to retain the positive aspects of the tall fescue-endophyte relationship while removing or reducing the quantity of the toxic alkaloids which cause fescue toxicosis researchers have developed novel endophyte varieties of tall fescue. Little research, however, has been done to investigate how the genetic alteration of the endophyte influences the other positive aspects of this relationship with particular regard to rhizosphere biogeochemical processes. Therefore, we grew in pure culture endophyte infected (E+), endophyte free (E-) and novel endophyte infected (En) tall fescue and characterized via high performance liquid chromatography (HPLC) the patterns and composition of root exudates in response to various inorganic (phosphorus deficiency and Cu toxicity), environmental (temperature) and biological (nematode) stimuli. The results of this work will help determine if manipulation of the TF-Neotyphodium symbiosis will reduce TF competitive ability and shed light on the larger ecological role that endophytic associations play in plant communities.