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 M. Fraser previously served as Commander, Space Warfare Center, Schriever Air Force Base, Colorado; as well as Commander, Alaskan Command, United States Pacific Command; Commander, 11th Air Force, Pacific Air Forces; and Commander, Alaskan North American Defense Region, with headquarters at Elmendorf Air Force Base, Alaska. Prior to his final assignment, he was Deputy Commander, United States Pacific Command, Camp H. M. Smith, Hawaii Douglas M. Fraser Douglas Malcolm Fraser (born April 16, 1953), is a retired United States Air Force general who served as the Commander, United States Southern Command (USSOUTHCOM). He was the first U.S. Air Force officer to become