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,
Fraser Canyon Gold Rush "humbug". Many returned to San Francisco. A continuing influx of newcomers replaced the disenchanted, with even more men storming the route of the Douglas Road to the upper part of Fraser Canyon around Lillooet; others got to the upper canyon via the Okanagan Trail and Similkameen Trail, and to the lower Canyon via the Whatcom Trail and the Skagit Trail. All these routes were technically illegal since the Governor required that entry to the colony to be made via Victoria, but thousands came overland anyway. Accurate numbers of miners, especially on the upper Fraser, are therefore difficult to reckon. During