Christmas tree cultivation has shifted toward the production of higher-quality trees, increasing land quality expectations as well. Indeed, some species of tree, such as the Fraser fir, are unable to grow on low-quality, marginal farmland. Flat or gently rolling land is preferred to that with steep slopes and inclines, which is prone to erosion and fluctuations in fertility. Noticeable obstructions, such as rocks, fences or significant underbrush, are also undesirable. Like all crops and plants, Christmas trees require a specific set of nutrients to thrive. There are 16 elements crucial for growth; of those, three are obtained through air and water: hydrogen, carbon,
Douglas E. Noble Grant in 2011 for research related to the Samuel Freeman House, a residence designed in 1924 by Frank Lloyd Wright. Together, Noble and Kensek have received several awards for their innovative "NotLY: Not Licensed Yet" support system for individuals preparing for the Architect Registration Examination. In addition to completing several buildings as an architect, Noble is a widely recognized leader in championing and mentoring emerging architecture professionals. Noble founded the Ph.D. program at USC Architecture, and he has published articles and organized symposia on doctoral education in architecture. Noble completed a Ph.D. in the Design Theories and Methods (DTM) group