Undergraduate epistemology typically transitions from an absolute perspective with a reliance on external knowledge authority to a more open epistemology that utilizes metacognition to evaluate knowledge claims. In the undergraduate agricultural classroom, student epistemic development, combined with deeply embedded agricultural beliefs and values, can lead to rigid perspectives that may inhibit effective communication and collaboration between diverse students, and thwart epistemic development necessary for students to entertain and synthesize widely divergent knowledge claims. This research sought to explore the characteristics and sources of knowledge undergraduates considered legitimate, and the internal processes undergraduate agricultural students used to assess the legitimacy of knowledge claims. Findings from this qualitative, multiple case study revealed students utilized specific metacognitive processes to assess the validity of conflicting agricultural knowledge claims. In addition, findings indicated students implemented specific legitimation criteria when assessing professors as credible sources of agricultural knowledge. These findings suggest educators should recognize and validate students' prior experience, social affiliations, and implement pedagogies that facilitate student learning through dialogue involving students holding diverse agricultural perspectives.