Forest Ecology - Delaware ENVIROTHON
Transcript Forest Ecology - Delaware ENVIROTHON
DELAWARE HAS 355,00 ACRES
OF FORESTED LAND!
Approx. 5,000 acres of timber are harvested
Delaware’s forest products industries
provide an excess of 3,700 jobs and and
generate an estimated annual wage of
# 34 Who Works in this Forest?
Delaware’s three state forests
total over 15,000 acres.
provide Delawareans the opportunity for
hiking, hunting, fishing, bicycling, and
are sustainably managed for wildlife
habitat, wood products, watershed
protection, education, and recreation.
# 32 A Forest of Many Uses
WE ALL NEED TREES
A BETTER WELL BEING
# 13 We All Need Trees & # 15 A Few of My Favorite Things
A forest is a community of trees, shrubs, herbs,
and associated plants and organisms that cover a
considerable area that use oxygen, water and soil
nutrients as the community attains maturity and
Forest Ecology is the study of the complex
interactions between the LIVING and
NONLIVING elements of a forest ecosystem.
# 48 Field, Forest and Streams
Living (biotic) Components of the
Producers (all green plants, trees, shrubs along with some
bacteria , also known as an autotrophs)
Consumers (organisms that eat plants and animals also
known as herbivores and carnivores)
Decomposers (bacteria, fungi, insects, or other organisms
that break down organic material)
Nonliving (abiotic) Components of the
Slope of land
There are over 346 species of
wildlife living in Delaware of
which 273 are forest
# 9 Plant Diversity & #22 Trees as Habitats
Healthy forests provide quality
habitat for wildlife
Blackbird State Forest contains the highest concentration of Delmarva Bays in
Delaware.–These freshwater wetlands are natural depressions that are home to
many species of animals and plants. Many theories exist to the origin of these
depressions, including “whale wallows” formed when Delaware was under the sea.
Current theories now include prehistoric meteor showers, retreating glaciers, and
The transfer of energy from sun to
producer to primary consumer to
secondary consumer to tertiary
consumer can be shown in a
Energy pyramids show
That the amount of
decreases down the food
It takes a large number of
producers to support a
small number of primary
It takes a large number of
primary consumers to
support a small number
of secondary consumers
ARE COMPRISED OF
ORGANIMS THAT ARE
Animals and insects have a huge
role in the forest.
1. decomposers breakdown organic matter
2. daily activity helps fertilize and aerate the soil
3. pollinators and seed dispersers
4. predators control harmful insects and mammals
# 23 The Fallen Log, # 24 Nature’s Recyclers & #26 Dynamic Duos
Animals and insects can also
become a nuisance or serious
threat to a natural setting.
•Excessive deer browsing on a forest’s seed crop
•squirrels and white footed mice girdle the trunks of young trees.
• insects may reach a population that require large aces of tree to
All trees compete for the same basic requirement
of life – light, water, essential elements, oxygen,
and other necessities.
The limiting factor in a forest ecosystem is
#27 Every Tree for Itself & #41 How Plants Grow
Symbiosis literally means the living together
of two dissimilar organisms, where one or the other, or
both are affected.
Usually involves supply of
all of the above
Mutualism is any relationship
between two species of organisms that
benefits both species.
Commensalism is a relationship between two
species where one species derives a benefit
from the relationship and the second species
is unaffected by it.
Parasitism is a relationship between two
species where one species benefits and the
other is injured.
Plants are parasitized by viruses, bacteria, fungi,
nematodes, and a few other plants.
THE ONLY THING CONSTANT
THEY NEVER STOP
fire, storms, drought, flood,
death and disease
harvesting, farming, trails,
development, and recreation
# 30 Three Cheers for Trees & # 81Living with Fire
Allelopathy involves a plant's secretion of
biochemical materials into the environment
to inhibit germination or growth of
surrounding vegetation. Allelopathy
enhances tree survival and reproduction.
Changes or disturbances spark the process called
succession, the gradual change in plants and
animal communities over time.
– Primary succession occurs in an area that has no true
soil. Pioneer species are the first plants to grow at
these barren sites.
– Secondary succession occurs on landscapes where
the natural vegetation has been removed or destroyed
but the soil remains intact.
# 80 Nothing Succeeds like Succession
What’s your tolerance?
Tree species that first colonize an area are usually
shade-intolerant species and must have full sunlight to
(pines, black locust, black cherry, yellow-poplar, sweetgum, blackgum, sassafrass,
Once they have developed some sun coverage the
shade-tolerant species will begin to grow and
eventually take over the canopy.
(oaks, hickories, and American beech)
These trees normally
are not the first to
colonize open areas.
Instead, they grow up
into an existing
These trees tend to:
- live a long time
- grow slowly
- have heavier seeds
Usually, these trees
are found in the
Intolerant species are
generally the “first in”
after an event such as
a clear-cut or a major
fire that substantially
opens the canopy.
These trees are often
called pioneer species.
These trees tend to:
- be fast growing
- be short-lived
- have light seeds
How does succession first begin in a disturbed area?
•animals carry seeds in fur
•wind blown seeds
•existing seed bank in soil gets the needed
•floods or high rains will leave behind seeds
# 43 Have Seeds Will Travel
Succession is healthy for a forest:
•since healthy forests are better able to
withstand and recover from stress the
outside environment imposes.
•by increasing the forest’s biodiversity
allowing other species to grow.
One of Earth’s most valuable resources:
Biodiversity is the variety and complexity
of species that are present and that
interact in an ecosystem, plus the relative
abundance of each.
One of the biggest threats to
# 9 Planet Diversity
Invasive species are organisms that are not
native to the area and have the ability to greatly
reduce the species richness (biodiversity) of an
A recent estimate has put the economic cost of
invasive plants in natural areas, agriculture, and
gardens at $35 billion per year.
#12 Invasive Species
Invasives often demonstrate:
* rapid growth
* prolific seed production
* high seed germination rates
* easy asexual propagation
* resistance to many types of control
Invasives are opportunistic organisms
that often use disturbances as their
gateway into a new area, from there
they can create monocultures and
seriously alter their surroundings.
Japanese Stilt Grass
Many plants were that are now considered invasives where
introduced to this area intentionally for their medicinal, ornamental,
and food value. Sometimes they “hitched a ride” in the soil, crop
seeds or the ballasts of ships.
Many do not have the natural controls that kept its population
in check and grow out of control, displacing many of our native
SUDDEN OAK DEATH
•FUNGUS THAT ATTACKS MEMBER OF
THE RED OAK GROUP
•NEEDS MEMBERS OF THE
BLUEBERRY FAMILY TO REPRODUCE
•CAN KILL LARGE TREES IN AS LITTLE
AS THREE YEARS
Major Forest Types
There are six major forest types in the
contiguous United States
– The Northern Forest
– The Central Forest
– The Southern Forest
– The Bottomland Forest
– The West Coast Forest
– The Western Interior Forest
Delaware is a unique state!
Delaware is a unique state because the
upper portion of the state lays in the Central
Forest type and lower Delaware is made up
of the Southern Forest type.
What is Silviculture?
Silviculture is the application of the
principles of forest ecology to a stand of
trees to help meet specified objectives.
Objectives can include income, wildlife
habitat, water quality, recreation, or any
other values a forest is capable of providing.
How do we DO silviculture?
Determine your goals for your forest.
Evaluate existing conditions in the forest.
Decide what treatments, if any, can help
you reach your goals.
Implement treatments at the right time.
Even-aged vs. Uneven-aged
Your management goals and the shade tolerances
of the species involved will determine whether to
manage on an even-aged or uneven-aged basis.
A Rule of Thumb:
For intolerant species, even-aged management
Use uneven-aged management for tolerant