If your tree has yellowing foliage, canopy dieback, broken or cracked branches, decay cavities, mushrooms growing on it or other defects, then you may be concerned about the health and safety of the tree.
Unless of course you’re a small woodland mammal. Or a songbird. Or an insect. Or a mushroom!
Trees that might appear risky to a human may be a cozy condo, a lunch buffet or a Home Depot of nest-building materials for countless other species. Some people have even compared ancient trees and forests to coral reefs based on the abundance and diversity of life that each supports.
Even city trees contribute to wildlife habitat, however, our obligations to protect public safety demand that we pay close attention to trees and tree defects that may be problematic. Although, a little birdie recently told me that new ideas in professional tree risk assessment and tree preservation may spare a few sparrows and other critters from needlessly losing their homes.
Attitudes, practices and technologies are evolving and some professionals are treating older trees and other trees with defects differently than they once did. Less-than-perfect trees still hold high value for wildlife habitat and other ecosystem services, so progressive tree managers are seeking opportunities to preserve such trees in cases when doing so will not jeopardize public safety.
This budding trend may lead to better management of mature tree canopy and increased wildlife habitat in urban areas, but time will tell.
Terms like “conservation arboriculture” and “ecological arboriculture” are gaining prominence in the tree industry. Today, these terms describe new ideas, but tomorrow they may be the norm for how we manage trees in the thriving urban ecosystems that we all—including wildlife—call home.
Here are a few resources to learn more about this shift in how we view our elder trees:
- Creating Wildlife Habitat Trees. A new class being offered by the Pacific Northwest Chapter of the International Society of Arboriculture, coming to Seattle in March of 2016.
- Snags—The Wildlife Tree. Washington State Department of Fish and Wildlife.
- Attracting Wildlife with Dead Trees. National Wildlife Federation.
- Conservation Arboriculture. Neville Fay, Arborist News, June 2011.