Last week, the sustainability officer of a local university contacted me. Each year, the university sets up a large Christmas tree in the center of its campus, has a lighting ceremony, and uses videos and photos from the event in its Christmas greeting materials. But sooner or later, the sustainability question had to come up: In financial or ecological terms, should we be annually cutting down a 15-year-old tree for four weeks of festivity? Could the school be and do better by planting and cultivating its own tree for long-term use?
Before addressing the school's sustainability question, let me kick the cultural sustainability elephant out of the room. In my opinion, the Christmas tree growers associations have done a good job demonstrating that the only sustainable thing about plastic trees may be the cost. As for the environment, in contrast to the negatives associated with producing plastic, Christmas trees are produced by farmers, not loggers. In other words, when you buy a tree, it's not like you are doing your little part to kill a forest: No more than when you buy a corn stalk for harvest decorations you are doing your little part to kill a prairie. Instead, the produce of a Christmas tree farm is harvested after a few years in the ground rather than a few months as with other crops. And, just like other crops, its ecological function should not be measured strictly in terms of what it does when it is harvested. In other words, a 15-year-old Christmas tree has been an ecological contributor for 15 years, and when it is harvested, it will be replaced not by pavement but by another ecological contributor.
So it is not necessarily unsustainable to purchase a Christmas tree every year. Yet to plant a Christmas tree may be more sustainable than cutting one, especially financially. But when we think of sustainability and Pennsylvania Christmas trees, we need to hear the perspective of organic tree farmers. They struggle to produce top-notch trees without chemicals, because the popular species of trees are not native here. For this reason, I recommended a Norway spruce. Though it is not native, it is naturalized. This means that it is completely adapted to growing here and can grow well without intervention. This does not mean that the tree can be left alone either. Left alone it will grow long, drooping boughs not suitable for intense decoration. So the tree should be regularly trimmed like a hedge in order to force dense shoot growth. But it is important to postpone cutting the central leader for as long as possible. Cutting this central shoot will make maintaining the desired conical shape more difficult.
In contrast to nursery recommendations, the tree should not be mechanically planted with a tree spade. Instead, dig a wide, shallow hole and backfill carefully.
Joshua Arp is an ISA-certified municipal specialist, Clarks Summit's municipal arborist and an operator of an organic lawn and landscape maintenance business. Reach him at firstname.lastname@example.org.