Natural Resource Inventory and Assessment - Town of Guilford

Uplands
D2
Ground cover includes the low ferns, wildflowers, mosses, grasses, and sedges that cover the forest floor.
Most are herbaceous, that is, not woody like shrubs or trees. Although not as conspicuous as the tree canopy,
ground cover plays an important role in the forest. Flowers provide nectar for migratory pollinators, the low
layer of vegetation provides cover for many creatures, and rotting leaves and logs break down to renew soil and
provide nutrients. Guilford’s forest floors reveal generations of trees that have died long ago. Shallow pits and
mounds indicate places where trees once fell, ripping up the roots and clinging soil. Eventually the roots
decayed, leaving behind mounds of earth next to the depression.
Forest Growth Stages: Forests vary in age, depending on when they last experienced a major
disturbance such as a powerful storm, disease outbreak, or clearing for timber or agriculture. In addition to
layers, a forest can be described as a series of growth stages. Guilford’s oldest forest stands are found in places
like ravines that were less accessible to clearing. Forest that grows after the first clearing is termed second
growth; much of Guilford is comprised of third- and fourth-growth forest. Over time, forests develop and
accumulate several “legacy” features that enhance their health and contribute to biological diversity. These
include the presence of fallen logs and rotting wood, a well-developed understory, complex structure, many of
which take hundreds of years to develop.
All components of forest vegetation – living trees and shrubs, dead and downed trunks and limbs,
standing snags (dead trees), microflora, lichens, mosses, and herbaceous plants –contribute to the diversity of
Guilford’s forests. In Connecticut tree cavities alone provide homes to treefrogs, 15 species of mammals, 20
species of birds, and many insects.
Like all of nature, Guilford’s forests are continually changing. Disturbance, which can cause rapid
changes, includes weather events like winter storms, hurricanes, windthrow (wind-toppled trees), and drought,
and logging, fire from lightning or human activity, and tree death from blights or pests like gypsy moth
caterpillar and wooly adelgid). Disturbances often create opportunities for plants to establish themselves,
because the soil has been exposed or sunny gaps have been created. In Westwoods, for example, beech and
black birch have colonized patches where hemlocks have died. Invasive species especially thrive in disturbed
soil, and often can outcompete native plants after a disturbance (See Threats subsection below.)
Guilford’s forests provide clues to past land use. Miles of crisscrossing stone walls reveal the extent to
which the land was once cleared for farming, pasture, and charcoal. Thick-trunked, spreading trees in the
middle of the forest (“wolf trees”) suggest trees that once stood alone in the open without crowding by
adjacent trees. An excellent example stands in Timberlands at the intersection of the Red and Yellow Trails.
Red cedars also serve as a clue that an area was once cleared (See Grasslands section.)
Although backyard woodlots have trees, they are not equivalent to intact forests. Forest edges are closer to
human activities and so impacted by associated threats. For example, certain animals can survive only in the interior
of large, intact forests, which are becoming increasingly rare in Connecticut, particularly in coastal towns such as
Guilford. Some of them are vulnerable to predators (e.g., raccoons, skunks, blue jays, domestic cats) and nest
parasites (e.g., cowbirds) that thrive in forest edges along clearings, but avoid deep forest. Others require large,
unfragmented forests to hunt and disperse, like fisher and bobcat, or closed a canopy, like scarlet tanagers (because
they hunt insects in the canopy) and worm-eating warblers (because they need unbroken stretches of forest).
Forest Types: Guilford supports a variety of forest types, groups of plants and animals that tend to be
found together and named after their dominant plants. Forest types concentrate in certain areas, depending
on terrain, soil type, land-use history, and other factors, and grade into each other across the landscape. A
description of each type follows.
Oak/Hickory Forest
Guilford is primarily comprised of oak/hickory forest. American chestnut dominated Guilford and the
rest of southern New England’s forests following the earliest cuttings by European settlers. When chestnuts
were effectively eliminated by a fungal blight in the early 1900s (See Threats subsection), oaks and hickories
replaced them in the canopy and today dominate the landscape.
Natural Resource Inventory and Assessment Town of Guilford, CT