Most everyone knows that we use proteins, carbohydrates and fats for energy. Calories are measurement of a unit of heat or food energy. For example, we can achieve four calories per gram of proteins and carbohydrates, and nine calories per gram from fats.
Tree Variety. Virginia pine (Pinus virginia) is the major Christmas tree species for the acidic soils found in East Texas. A grower can produce a 6- to 8-foot Virginia pine Christmas tree in 3 to 5 years, depending on soil and climatic conditions.
Not all natural Christmas trees harvested are grown on plantations. In British Columbia, Canada, for example, most of the 900,000 trees harvested for use as Christmas trees came from native pine and fir stands.