Christmas trees grow on farms. They are an agricultural commodity. Their unnatural and intensive cultivation is no asset to any associated natural ecosystem. Their harvest does not deprive ecosystems of natural components. Live Christmas trees are at least equally as unnatural. Their cultivation involves more synthetic materials and unnatural irrigation.
There should be no shame associated with the procurement of cut Christmas trees. They are merely cut foliage that is significantly more substantial than that which accompanies cut flowers. Furthermore, live Christmas trees are not an ecologically responsible option. They are merely potted plants that can be difficult to accommodate within home gardens.
That certainly should not invalidate the appeal and potential practicality of live Christmas trees. With proper maintenance, other potted plants, such as houseplants, can grow and perform for many years. Since live Christmas trees are coniferous species that get rather large, they demand more attention. All are not necessarily totally unmanageable though.
Some compact conifers, such as dwarf Alberta spruce and compact cultivars of Colorado blue spruce, can remain within pots for many years. They need either larger pots as they grow, or occasional root trimming if they stay within their same pots for a few years. Their roots outgrow pots as slowly as their canopies grow. They also require diligent watering.
Unfortunately, the most common of decorated live Christmas trees that are available from supermarkets are also the most problematic. Most are either Canary Island pine or Italian stone pine, which grow surprisingly large for such seemingly innocent small evergreens. They very often go into compact gardens, where their bulky roots displace infrastructure, such as pavement and turf grass.
Contrary to popular belief, planting live Christmas trees in the wild after Christmas is not a practical option. Because their roots were confined to pots, they rely on irrigation while they disperse roots into the ground. They can not survive without irrigation after the rainy season. Besides, trees that are not native could be detrimental to the native ecosystems.