Undergraduate biology labs often explore the techniques of data collection but neglect the statistical framework necessary to express findings. Students can be confused about how to use their statistical knowledge to address specific biological questions. Growth in the area of observational ecology requires that students gain experience in sampling design and the scope of inference relevant to observational studies. I developed a laboratory-based guided inquiry that illustrates these concepts by comparing ponderosa pine ("Pinus ponderosa") trees in northeastern Washington State. This approach presents a hands-on experience whereby students apply the statistics they learn in the classroom to a field-based investigation, giving students an appreciation of the design and interpretation of observational studies in ecology.