As arborists and urban foresters, we are hired for our
knowledge of trees and forest management. But trees
are part of an ecosystem, and we know they cannot
thrive unless the conditions around them are optimal
for growth. The Forest Service has learned a tremen-
dous amount about best management practices through
the study of biodiversity and urban forest habitats
for birds and bees; this article will highlight some of
these findings and their implications for those of us
seeking to grow healthy and thriving trees and forests.
Habitat Considerations
The urban forest provides many ecosystem benefits,
including carbon sequestration, shading, air and water
pollution reduction, and stormwater runoff mitiga-
tion. The urban forest also provides wildlife habitat for
birds, bees, and other animals. Rapid habitat assess-
ment tools can increase our capacity to assess bird
habitat potential within the urban forest and to evaluate
existing habitat improvement plans, and can provide
detailed information about habitat requirements.
A newly developed wildlife habitat module integrates
bird habitat relationship models into i-Tree Eco, the
USDA Forest Service urban forest assessment tool.
This makes it possible to use i-Tree urban forest data-
sets to calculate the overall bird habitat suitability for
a city or a delineated i-Tree project, and the habitat
suitability for different types of land use (e.g., resi-
dential, commercial, parkland) for each bird species.
By combining and augmenting decades of bird data
with i-Tree, researchers and managers can create and
quantify countless targeted assessments, detailed
predictions, and visual components that can guide
land management decisions across the northeastern
U.S. and eventually, beyond (Lerman et al. 2014).
Managing the urban forest for cavity-nesting species
can be particularly challenging. Species like red-bel-
lied woodpeckers and black-capped chickadees nest in
the dead and decayed stems and branches of different
types of trees. From a habitat management perspective,
letting dead and dying wood remain in the landscape
can provide critical habitat for these and other species.
However, dead and dying trees may also have a greater
risk of failing and, in a developed setting, may lead to
personal injury and damaged property. Research from
western Massachusetts and Baltimore, Maryland sug-
gests partial pruning rather than complete removal
of the tree might strike a balance between reducing
risk and retaining habitat (Kane et al. 2015). >>
From the USDA Forest Service and Partners
W hat are the
Birds and Bees
Telling Us?
By Susannah Lerman, Vince D'Amico, and Phillip Rodbell
urban-forestry.com 35
