Part I: Brainstorm and Cluster (as a class – allow
- Review: the forest health glossary prior
to the lesson or as you go along.
- Mention: just as humans get sick so
- Brainstorm: living (biotic) and non-living (abiotic) factors
that affect the health of a
forest. Record their answers on the chalkboard or overhead.
some signs that a tree is unhealthy. (Possible answers: change
colour, broken branches, mushrooms around the base of the tree,
sap running down
the trunk, fungus growths on the branches/trunk, etc)
Part II: Lesson (as a class – allow 40+ min.)
- Have the students fill in Worksheet #1 (Forest Health) as you go through
- For more details on each living factor refer to the Teacher
Background (TB) section
that is noted.
1. Non-Living (Abiotic) Factors
- Discuss: how non-living (abiotic) factors affect the health
of a forest.
- Prolonged periods of hot and dry weather
conditions – lack
of water causes stress
to the tree decreasing its ability to defend
itself from disease and insect attack.
Extreme drought conditions can cause trees to die.
- Windstorms – High
velocities of wind can uproot trees, causing them to die.
Wind can also break branches allowing diseases
to enter into the tree more readily.
- Fire – Forest fires often kill
many trees, however they allow new healthier forests
to regenerate. Fire can destroy insects
and disease, therefore increasing the overall
health of the forest.
2. Living (Biotic) Factors
a) Tree Diseases
- Mention: living (biotic) factors that affect the health
of the forest are either
a disease or an insect and they
attack different parts of the
- Show overhead: #1 Tree Disease Chart - discuss one
column at a time.
- Show overheads: #2 Foliar Disease (TB1),
#3 Wood Decay (TB2), #4 Mistletoe
(TB3), #5 Root Disease
b) General Insect Biology
- Explain: more living factors that affect
the health of a forest are insects.
- Show overhead: #6
Insect Biology - review the general biology and
life cycle of
the insect. Distinguish between
the 2 life cycles: complete and incomplete
metamorphosis and mention that the insects that you
are going to talk about
undergo complete metamorphosis.
c) Defoliating Insects
What type of insect would affect the foliage of a tree?
some insects are called defoliators (they defoliate/eat
the needles and leaves of
- Discuss: How do you think defoliating insects affect
the health of the tree?
Remind the students that the foliage is where photosynthesis
occurs and without
foliage the tree cannot make sugars to feed the tree.
This can stress the tree and
make it susceptible to attacks from other pests.
- Show overhead:
#7 Defoliating Insects: (TB5)
d) Gall Adelgids [a-del-jid] (Aphid-like Insects)
- Mention: there are other insects that affect
the foliage of the tree. They are called
gall adelgids (aphid-like insects).
- Show overhead: #8 Gall
e) Bark Beetles
- Discuss: What type of
insect would attack the inner bark of the tree? Mention
how bark beetles are some of the most damaging
- Discuss: the general biology of bark beetles. (TB#7)
overhead: #9 Bark Beetle Chart
f) Weevils (snout beetles)
- Mention: there are other beetles that affect
the health of trees.
- Show overhead: #10 Weevils: (TB8)
g) Wood Borers
- Show overhead: #11 Wood Borers: (TB9)
Closure (allow 10+ min.)
- Mountain Pine Beetle DVD (from Market Outreach – BC’s
- Journal Entry - have students write 3 new interesting
learned from the
- Worksheet #2 (Create your own Forest Pest) – 1
per student or
get students to do the
assignment on poster paper. (Insect
biology overhead should be displayed)
- Guest Speaker from MOF
- Mountain Pine Beetle Lesson (from Market Outreach – BC’s
- General Forest Health Lesson (from www.learnforestry.com)
- Force of Fire
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