Woodland Ecosystems
March 2014
Riverina Environmental Education Centre
Table of Contents
1. Ecosystems and plant communities
21. Adaptations: cypress pine
2. Australia's vegetation
22. Adaptations: casuarina
3. Woodland or forest?
23. Adaptations: acacia
4. Woodland tree density
24. Food chains and webs
5. Shrub or grassy woodland?
25. Herbivory
6. Box gum grassy woodlands
26. Interactions: allelopathy, commensalism
etc
7. Woodland trees
27. Kangaroo survey
8. Woodland, a critically endangered
ecological community
28. Human impact: contour banks, reserve,
fenced, signage
9. Limiting factors: soil nutrients
Articles and resources
The following pages are a case study of a
reserve behind the Riverina EEC to assist
students doing fieldwork at the Centre
Grassy white box woodlands(article)
Structural classes (table)
10. Case study: Red Hill Reserve
Shade density (table)
11. Abiotic factors: landform
Soil changes (article)
12. Abiotic factors: soil
BGGW Recovery Plan (article)
13. Abiotic factors: climate
Effect of soil phosphorus (research article)
14. Biotic factors: plant distribution (transect)
Effect of soil phosphorus (research article)
15. Biotic factors: plant diversity (quadrat)
Squirrel glider NSW Scientific Committee
16. Distribution & abundance: small-leaf pea
17. Distribution and abundance: animal squirrel glider
17b. Squirrel glider tree spacing
18. Adaptations: general
Squirrel glider: recovering endangered
populations
Recommended resource: A guide to
managing box gum grassy woodlands by K.
Rawlings, D. Freudenberger and D. Carr.
Commonwealth of Australia 2010
19. Adaptations: eucalypt
20. Adaptations: pea
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1. Ecosystems and plant communities
You will be using the following terms during this study.
Ecosystem
Any given space in which plants and animals interact with each other and the abiotic or
physical environment.
Ecological community
A group of populations of plants and animals in a given place.
Plant community
A group of populations of plants in a given place.
The following characteristics can be measured and used to compare different plant
communities.

Structure: the number of vertical height layers of plants. The physical layering is
important because generally the more height layers of plants, the richer the habitat
and the more animals supported.

Form: the shape of the plants. The main forms are: trees, shrubs, grasses, herbs,
mosses and lichens.

Species diversity: the number of different species.

Abundance: the number of plants of each species. Some species may have large
populations and others, although present may be represented by only a few plants.

Dominance: not all species are equally important. Some species determine the
conditions under which others live. A tall tree may shade all plants beneath it or
release a chemical inhibiting the growth of other plants.
2. Australia's vegetation
(Based on work by the Australian National Botanic Gardens
http://www.anbg.gov.au/index.html)
The most widely recognised classification system for Australian vegetation was developed
by Specht (1970) and defines structural forms of vegetation in terms of the dominant plant
form and the percentage of crown or foliage cover of the tallest plant layer.
In this classification, a tree is defined as a woody plant more than 5 m tall, usually with a
single stem. A shrub is a woody plant less than 8 m tall, frequently with many stems arising
at or near the base.
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Structural forms of vegetation (based on Specht 1970)
Projective foliage cover
Approximate crown cover %
70-100%
30-70%
10-30%
< 10%
> 80%
50-80%
20-50%
< 20%
Form and height of tallest layer
Structural formation classes
Trees > 30 m
Tall closed-forest
Tall open-forest
Tall woodland
Tall open-woodland
Trees 10-30 m
Closed-forest
Open-forest
Woodland
Open-woodland
Trees 5-10 m
Low closed-forest
Low open-forest
Low woodland
Low open-woodland
Shrubs 2-8 m
Closed-shrub
Open-shrub
Tall shrubland
Tall open-shrubland
Shrubs 0-2 m
Closed-heath
Open-heath
Low shrubland
Low openshrubland
The vegetation classification used above can be a little confusing with the terminology used
for crown and foliage cover.
Crown cover is the percentage of the study site
covered by crowns. The crowns are considered
opaque, as though they let no light through.
Foliage cover is the percentage of the site covered
by crowns but adjusted for the amount of light let
through by the leaves and woody branches
because many crowns, particularly in woodlands let
some light through.
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Projected foliage cover is the same as foliage cover but takes into account seasonal
variation. Some plants are summer or winter deciduous and drop some leaves.
Note: when you stand under a single tree and look up, you are looking at the foliage cover of
that tree. The classification used above is for the percentage of the whole site or sample
area covered by crowns.
3. Woodland or Forest?
Before starting, download and print two items:

article, 'Grassy White Box Woodlands',
4 pages and read the first two paragraphs.

table, 'Structural formation classes' by Specht
The table on 'structural formation classes'
classifies a plant community as a forest,
woodland or shrubland etc. The classification
is based on the height of the dominant layer,
usually the tallest layer and the percentage
crown cover for the site.
Describe the vegetation community in photo
one.
Include:




height
formation
dominance and
structure
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Describe the vegetation community
in photo 2.
Include:




height (see scale next to tree
in centre of photo)
formation
dominance and
structure
4. Woodland tree density
"Healthy box gum grassy woodlands typically have widely spaced trees (30-40 per ha) with a
grassy groundcover which includes a stunning diversity of wildflowers."
From 'A Guide to Managing Box Gum Grassy Woodlands'. Rawlings, Freudenberger,Carr,
p4, 2010
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Below is a representation of a one hectare quadrat you are studying in a woodland.
Calculate:


a. tree density
b. projected/percentage foliage cover of the vegetation along the transect A-A.
The shade density of the trees in the transect is given below the transect. To
calculate projected/percentage foliage cover, estimate the percentage crown cover
along the transect and multiply it by the percentage foliage cover e.g. if the crown
cover is 50% and each crown has a foliage cover of 50% then 0.5 X 0.5 = .25 or 25%
When studying woodlands we normally use projected/percentage foliage cover
instead of crown cover because woodland trees have a fairly open canopy, they are
not opaque.
Structural forms of vegetation (based on Specht 1970)
Projective foliage cover
Approximate crown cover %
70-100%
30-70%
10-30%
< 10%
> 80%
50-80%
20-50%
< 20%
Form and height of tallest layer
Structural formation classes
Trees > 30 m
Tall closed-forest
Tall open-forest
Tall woodland
Tall open-woodland
Trees 10-30 m
Closed-forest
Open-forest
Woodland
Open-woodland
Trees 5-10 m
Low closed-forest
Low open-forest
Low woodland
Low open-woodland
Shrubs 2-8 m
Closed-shrub
Open-shrub
Tall shrubland
Tall open-shrubland
Shrubs 0-2 m
Closed-heath
Open-heath
Low shrubland
Low open-shrubland
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5. Grassy or shrubby woodland
Read the rest of page 1 of the article, 'Grassy White Box Woodlands'.
Compare the two woodlands below and classify them as either grassy woodland or shrubby
woodland.
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6. Box Gum Grassy Woodlands Distribution
The map shows the original distribution of the Box Gum Grassy Woodlands (BGGW) across
much of south-eastern Australia. "Now, less than 5% of the original BGGW remains in good
condition. What remains exists in small, isolated patches....
From 'A Guide to Managing Box Gum Grassy Woodlands'. Rawlings, Freudenberger,Carr,
p1, 2010
Describe the distribution of BGGW in more precise terms than 'south-eastern Australia'.
Draw a sketch map to show it's location. Include state borders and some town names.
Describe the extent of land clearing.
A false colour satellite image taken
by Landsat 7 which orbits
approximately 700 km above the
Earth in a near polar orbit. Each
side of the image is approximately
180 kilometres long.
The Murrumbidgee Irrigation Area
and Coleambally Irrigation Area
show as green areas to the west.
Dryland farming areas show as light
browns/mauve and light green.
Areas of uncleared woodland and
other remnant vegetation appear as
distinct black areas, often with
straight sides. Note: not all of the
black areas are woodland. It
includes some cypress pine and
other vegetated areas.
Estimate the percentage of remnant vegetation shown in the image.
This also represents the amount of natural habitat left for native animals.
Satellite image: Landsat 7 image acquired and processed by ACRES.
7. Box Gum Grassy Woodland trees
The major tree species in BGGW are eucalypts. The word comes from the Greek eu (well)
and kalyptos (concealed). There is a cap covering the flower bud which falls away on
flowering in all members of this group. See flower bud photos below.
BGGW is characterised by the presence of white box, yellow box and or Blakely's Red Gum.
Other trees may be present such as grey box and stringybark.
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White Box
Yellow Box
Blakely's Red Gum
Eucalyptus albens
Eucalyptus melliodora
Eucalyptus blakelyi
Bark
Woody fruit
Flower
buds
Images courtesy Toni McLeish
8. BGGW, a critically endangered ecological community
"White Box-Yellow Box-Blakely's Red Gum Grassy Woodland and Derived Native Grassland
is listed as a critically endangered ecological community under the Environment Protection
and Biodiversity Conservation Act 1999. The ecological community can occur either as
woodland or derived native grassland (i.e. grassy woodland where the tree overstorey has
been removed). It is characterised by a species-rich understorey of native tussock grasses,
herbs and scattered shrubs (where shrub cover comprises less than 30% cover), and a
dominance or prior dominance of White Box (Eucalyptus albens) and/or Yellow Box (E.
melliodora) and/or Blakely's Red Gum (E. blakelyi) trees.
To be considered part of the listed ecological community remnant areas must also:

be 0.1 hectare (ha) or greater in size and contain 12 or more native understorey
species (excluding grasses), including one or more identified important species (see
Appendix 1)
or
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
be 2 ha or greater in size and have either natural regeneration of the overstorey
species or an average of 20 or more mature trees per ha.

have a predominately native understorey (i.e. more than 50% of the perennial
vegetative groundlayer must comprise native species)
From: Department of Environment, Climate Change and Water NSW. 2010. Draft National
Recovery Plan for White Box - Yellow Box - Blakely's Red Gum Grassy Woodland and
Derived Native Grassland. Department of Environment, Climate Change and Water NSW,
Sydney.
Download the full recovery plan (Word, 85 pages) for a comprehensive account of the
BGGW and management.
Definitions of threatened, endangered etc. (Word, 1 page)
9. Limiting factors: soil nutrients
"Increased soil nutrient status as a consequence of fertiliser application, run-off and
spray drift from adjoining paddocks, soil disturbance or stock camps causes changes
in soil structure and soil biota and results in a more favourable environment for
weeds. Changes to the soil nutrient status can result in a loss of native understorey
species and dieback of overstorey species
(Windsor 1999), with negative flow-on effects to the fauna assemblage."
From: Department of Environment, Climate Change and Water NSW. 2010. Draft
National Recovery Plan for White Box - Yellow Box - Blakely's Red Gum Grassy
Woodland and Derived Native Grassland. Department of Environment, Climate
Change and Water NSW, Sydney, page 19.
"Three of the most essential soil nutrients are phosphorus, nitrogen and carbon.
When these nutrients get too high, they can disadvantage native plants.
Many native Australian plants have evolved mechanisms to cope with the commonly
low phosphorus levels in Australia's ancient soils.
The addition of phosphorus usually in the form of superphosphate, disturbs the
natural balance of phosphorus in the soil, and helps increase the availability of
nitrogen to plants. This creates a competitive advantage for many weeds that have
evolved in higher phosphorus environments."
From 'A Guide to Managing Box Gum Grassy Woodlands'. Rawlings,
Freudenberger,Carr, p57, 2010
Scientific research article on impact of phosphorus.
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Scientific research article on phosphorus. Three pages have been copied, the
abstract and two on data collection (methods).


List the conclusions given in the abstract above.
Describe the methodology, particularly the number and size of quadrats and
the number of soil samples taken in each quadrat in the second article.
10. Woodland case study: Red Hill Reserve
Following pages are a case study of Red Hill Reserve behind the Riverina Environmental
Education Centre which is used for woodland fieldwork. Note this is a Box Gum Shrubby
Woodland, not a grassy woodland.
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Study site location
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Draw a sketch map to show the general location of Red Hill Reserve in relation to Wagga
Wagga.
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11. Abiotic (physical) factors: landform
General climatic factors such as air temperature, wind and moisture don't vary much over
small areas but hilly terrain causes different micro-climates. Different plants will be adapted
to different micro-climates which will affect their distribution and abundance.
Aspect, the direction a
slope is facing, will
influence the amount of
sunlight the ground
receives. In this region,
the coolest aspect is
generally south and the
hottest, west.
Aspect can be
recorded as cardinal
compass directions
such north and south
etc or as a bearing
using the 360 degrees
in a circle e.g. east has
a bearing of 90
degrees.
Below are photos of
sites 1, 3 and 5 along
the transect. The red
line represents the
average slope of those sites.
Gradient is the steepness of a slope.
Water runs down hill because of gravity.
Soils higher on a slope are usually drier
than soils lower down a slope where
water collects.
Site 1
Site 3
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Site 5
12. Physical factors (abiotic)
Below are soil profile
descriptions for three sites 1, 3
and 5 along the transect. These
soils have formed topsoil and
sub-soil layers which have
different characteristics. The
topsoil is dominated by the
cycling of organic matter from
dead plants and animals, the
sub-soil by the mineral fraction
from the weathered rock
beneath.
The geology at the three sites is the same so soil differences between the three sites are the
result of micro-climate, landform and vegetation differences.
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Soil texture
The proportion of sand, silt and clay size particles used to classify the soil as a sand, loam or
clay.
Colour
Iron oxides in the soil are different colours depending on the moisture status of the soil. This
particularly influences the colour of the subsoil where there is more clay containing iron. Humus
stains the soil a dark colour, particularly the topsoil where there is more decaying plant material.
pH test
pH indicates whether the soil is acidic (under 7), alkaline (over 7) or neutral (7).
Describe how soil depth and colour vary between the three sites. Give reasons for the
changes.
13. Abiotic (physical) factors: climate
Temperature and moisture are two very important factors limiting the distribution of life on
earth. Below is the average monthly temperature and rainfall data for Wagga Wagga.
Monthly average climatic statistics for Wagga Wagga
Ave.
J
F
M
A
M
J
J
A
S
O
N
D
Temp.
23.8 23.7 20.8 16.2 11.8 9.0
( 0 C)
7.8 9.1 11.7 15.0 18.2 21.2
Precip.
44
(mm)
53
39
43
45
54
43
54
52
65
42
35
Monthly average temperatures are obtained by adding up all the average temperatures of
the days in the month and then divided by the number of days.
"If temperature acts to limit a distribution, what aspect of temperature is relevant- maximum
temperatures, minimum temperatures, average temperatures or the level of temperature
variability?" (Ecology The experimental analysis of distribution and abundance,
Charles Krebs, p67)
Temperature and humidity were recorded each hour for a
number of days in July and January. This data gives an idea
of variability not shown by monthly averages. Was there a
one off 'killer' frost or a one off extremely hot 'lethal'
afternoon which exceeded a plants survival limits?
Spreadsheet of data attached

Graph temperature and humidity together. Describe
the relationship between temperature and humidity.
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
The monthly average temperature for July is 7.8 degrees. What was the lowest
temperature recorded by the data loggers at the three sites in July? Give the site,
date and time.

The monthly average temperature for January is 23.8 degrees. What was the highest
temperature recorded by the data loggers at the three sites in January? Give the site,
date and time.

At what time of the 24 hour day/night cycle do the coldest temperatures typically
occur in either summer or winter. Give reasons.

At what time of the 24 hour day/night cycle do the hottest temperatures typically
occur in summer. Give reasons.
14. Biotic factors: plant distribution
Most areas of bush are too large to identify and count every single plant so small,
randomly selected, representative areas called transects and quadrats are used to
sample the woodland. Transects can be just a line such as a length of rope placed
through the bush and plants touching or on either side are identified and counted.
Transects show spatial changes in vegetation communities such as down a slope or
across a valley.
You have chosen to
study the western side
of Red Hill Reserve in
the vicinity of the
transect marked on the
photo. You want to find
if the tree species
change down the hill.
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You need to do a number
of transects, by doing only
one, you may miss
important plant species.
You also need to randomly
select your transect
locations so you do not
have a biased survey.
Three tree species are
found at this site.
Blakely's Red gum
Yellow box
White box
The map below is a representation of the site.
Transects will be 120m long by 10m wide. Make 3 transects at different locations. At
each location record the tree species and their distance along the transect. Make the
transects random.
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
Show your results as the distribution of trees on a landform profile diagram
similar to the one below.

Describe the distribution of trees at the study site.

What abiotic and biotic factors may have influenced the distribution of trees?
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15. Biotic factors: plant diversity (quadrats)
Quadrats are another sampling method. Quadrats can be any size or shape
depending on the needs of the survey. Below is a woodland site with a small quadrat
to survey the understorey.
Below is an exercise in using quadrats based on the site above. One quadrat, 50m X
50m will be used to survey the trees which are more dispersed and a smaller
quadrat, 20m X 20m will be used to survey the understorey and ground cover plants.
Compare the abundance (number) of the different species. Randomly choose a site
to place a small quadrat square on. Count the number of each species wholly inside
the square or touching the sides. You need to do 3 sample areas for trees and three
for ground cover.
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red gum
white box
paper daisy kangaroo
grass
parrot pea
Make tables of your results
Trees
Red Gum
White box
Quadrat 1
Quadrat 2
Quadrat 3
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rock fern
small leaf
pea
paper daisy
Understorey and ground cover
kangaroo grass
parrot pea small leaf pea
Quadrat 1
Quadrat 2
Quadrat 3

Describe your methodology.

Describe your results (abundance of species).

Do the trees influence the distribution of understorey plants?
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rock fern
16. Distribution and abundance: small-leaf pea
To investigate the distribution and abundance of small-leaf pea shrubs in Red Hill
Reserve, Wagga Wagga, NSW.
Close up of individual leaf. Hairs
(trichomes), protect the stoma from the
wind. Hairs create a boundary layer of
dead air over the leaf surface reducing
transpiration.
Small-leaf pea shrub
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Quadrat 1
Q1 (0 m)
Quadrat 3
Q2 (25 m)
Q3 ( 50 m)
Quadrat 5
Q4 (75 m)
Q5 (100 m)
Individual pea shrubs are shown by

Comment on the adaptations of this plant to a dry environment.

Comment on the distribution and abundance of the small-leaf pea.

Give possible reasons for this distribution. Give several possible explanations.
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General body shape: oval shape, streamlined, 11 cm long,
7.5 mm wide
General parts: head, thorax, abdomen
Head: 2 eyes, 2 antennae (3 mm long)
Thorax: 6 legs, three each side; wings not visible but known
to be present beneath outer hard covering protecting
abdomen
Colour: Head and thorax light brown with saddle of darker
brown between eyes. Abdomen, darker brown
Legs: jointed
first pair smaller, 2 mm, claws on end
second pair, 3 mm, claws on end
third pair larger, 6 mm, many hairs, probably for swimming
(guess)
17. Distribution and abundance: squirrel glider
Description
Make an annotated sketch of the squirrel glider in the photo and describe it in as
much detail as possible. Use the example of the water beetle to guide you. Check
your answer by the descriptions given in the two articles at the bottom of the page.
Distribution
The species is distributed widely in eastern Australia, from northern Queensland to
Victoria.
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Habitat (Photo: Pat Murray)
"The Squirrel Glider requires hollow-bearing,
floriferous eucalypt open forests and woodlands with a
Banksia or Acacia shrub layer, that provide den sites
in tree cavities and a good winter supply of nectar.
Large trees with abundant hollows are critical
elements (Holland et al. 2007; Crane et al. 2008).
Preferred hollows are those with a large cavity that can
house multiple gliders in a large nest, yet with a small
entrance that protects the group from predators like goannas."
NSW Scientific Committee (2008) Squirrel Glider Petaurus norfolcensis.
Diet
"The Squirrel Glider feeds on nectar, pollen, plant exudates (e.g. wattle and eucalypt
sap), invertebrates, and honeydew (sugary exudate from insects), and rarely small
vertebrates such as nestling birds" NSW Scientific Committee (2008) Squirrel Glider
Petaurus norfolcensis.
Threats


Loss of mature and old-growth trees reducing the availability of hollows.
Loss of food resources.
Conservation actions
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


Retention of old growth and mature trees with hollows.
Retention of shrub understorey for feed resources.
Creation and maintenance of vegetation corridors between feeding areas.
Read the attached scientific research articles on squirrel gliders and management.


Article 1 Recovering endangered populations in fragmented landscapes: the
squirrel glider, A. Claridge and R Van der Ree 9 pages. Excellent article
showing distribution and abundance
Article 2 NSW Scientific Committee, Review of current information, Squirrel
Glider, 8 pages
From the articles, describe the distribution and abundance of squirrel gliders.
17b. Squirrel glider tree spacing
Squirrel gliders have a glide angle of about 28 degrees. Any steeper (over 28
degrees) and the glide is too fast to land safely. Anything under 28 degrees and the
glide is too flat and the air flow over the membrane between the legs is likely to stall
and the glider falls.
What are the implications for squirrel glider habitat considering the glide angle and
the need to stay off the ground because of predators such as cats and foxes?
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18. Adaptations: plants, general
Basic Needs of Plant
Plants are photosynthetic organisms so they have basic requirements of: light, water
and carbon dioxide for photosynthesis; oxygen for respiration and a few inorganic
ions such as phosphorus and potassium. Plants have evolved to obtain these from
their particular environment.
Light Absorption
Photosynthesis occurs in cells containing chlorophyll. Leaves have evolved as an
organ to hold the chlorophyll out to the sunlight. This has led to a number of other
adaptations. To prevent leaves from being shaded out by other plants, there is an
advantage in being tall. Trees with trunks have an advantage in being able to grow
tall.
Gas Exchange
Nearly half the dry weight of most plants is carbon. Plants obtain this from carbon
dioxide gas through the process of photosynthesis. A waste product of this is oxygen
which is removed from the plant. Again this process occurs in the leaves.
Some plants have very small leaves, others which hold their leaves out flat have
most of the stomata on the underside away from the sun. All above ground plant
parts are covered by cuticle, a waxy coating which retards water loss.
Eucalypt leaf with thick waxy
cuticle.
Grevillea leaf with reduced
surface area.
Acacia bi pinnate leaf with
reduced surface area.
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Terrestrial plants have developed stomata which are openings in the leaf surface for
gas exchange to occur. One problem is the loss of water from the plant when
stomata are open. Plants have evolved many adaptations to reduce water loss
through leaves.
Electron micrographs of urn heath leaf showing how the leaf has rolled up to protect the
stomata, left and closer view at right. Photos courtesy Geoff Burrows.
Support
Support is a problem for terrestrial plants wanting to grow tall to get more sunlight
(less shading from other plants) and needing to have leaves held out for
photosynthesis. Shrubs and trees have woody stems which contain cells
strengthened and thickened with lignin. Sclerenchyma and xylem cells are important
for this.
Water Balance
In terrestrial plants, the root system is well developed as it has the major function of
anchoring the plant and also collecting most of its water needs. Roots also collect
inorganic nutrient ions. Water loss is a big problem. A major supporting mechanism
to hold leaf shape is cell turgor, water pressure within cells supports the leaf like
balloons. If turgor is lost, the leaves will wilt and physically damaged. Terrestrial
plants have the ability to close stomata with special guard cells. Cuticle and bark
also protects the leaves and trunk from water loss.
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19. Adaptations: eucalypt

Named after the covering on the seed
capsule (operculum). From the Greek
Kalyptos meaning well covered.

The capsule is woody for fire protection.
Trees may have viable capsules which are
two or three years old.

Seeds are released when the twig dies and
the capsule dries out. This results in a slow
release of seeds throughout the year. Ants
eat most of the seeds.

After fire, there is a massive seed release. The ants cannot eat all of these, so
some germinate to become trees. There is also an "ash bed effect" of
nutrients released by fires and this combined with less competition from other
plants allows better survival of young trees.

Eucalypts have both adult and juvenile leaves. The juveniles are usually a
different shape and do not grow into adults. Often the juveniles have no
petiole, are paired on the twig, are held out to the sun and are softer.

Adult leaves have a petiole (stalk), a thick waxy coating and hang vertically.
By hanging vertically less surface area is exposed to sunlight, reducing
transpiration. Eucalypts usually have equal numbers of stoma on each side of
the leaf. Trees which hold their leaves horizontally usually have nearly all
stoma on the lower side.

Eucalypt trees are evergreen and live for 2-3 years.

Most have epicormic shoots which sprout after
defoliation due to fire or insect attack. These
shoots may come out of the trunk and are from
dormant buds.
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
Epicormic shoots have juvenile leaves and indicate the tree is under stress.

To endure drought conditions, eucalypts have not reduced their leaf area
through evolution they have other adaptations such as scleromorphic leaves
which are leathery. This tough, leathery nature comes from hard
sclerenchyma tissue in the leaves which allows them to withstand severe
wilting. They have a very large root system and an ability to extract water from
quite dry soil.

Thick bark protects the cambium (growing layer) layer from fire.

Most eucalypts have a lignotuber, which is a mass of woody tissue with
dormant buds and food reserves just beneath the ground as part of the root
system. After a fire which has damaged the trunk several shoots may appear
resulting in multiple trunks (coppicing).
Go into the school grounds and find examples of the above adaptations. Take
photos of them, print the photos on to a page and label them.
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20. Adaptations: pea
The leaves of the small-leaf pea and the parrot pea are reduced in size. Leaves of
the small-leaf pea (Pultenaea foliolosa) have many fine hairs to reduce transpiration.
The hairs act like a jumper and trap a moist layer of air next to the leaf. Leaves of the
parrot pea (Dillwynia sericea) are curled into a cylinder which reduces surface area
and protects the stoma protected inside.
Small-leaf pea (Pultenaea foliolosa)
Small-leaf pea
Parrot pea (Dillwynia sericea)
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22. Adaptations: black cypress pine
Black cypress pine is not normally associated with Box Gum Grassy
Woodland but some are found in Red Hill Reserve associated with
the shrubby woodland. The leaves of the black cypress pine
(Callitris endlicheri) have been reduced to 'leaf scales' with the
stoma located on the underside to reduce water loss by
transpiration.
Electron micrographs of cypress pine leaf scales. Photo at right shows stomata protected beneath scale leaf
reducing water loss. Photos courtesy Geoff Burrows.
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22. Adaptations: drooping
she oak (Allocasuarina verticillata)
The drooping she oak is not commonly
found in box gum grassy woodlands but
some specimens are found in Red Hill
Reserve and they occur in the adjacent
Pomingalarna Reserve as a threatened
ecological community.
The leaves of casuarina trees have been
reduced to small "leaf teeth" to reduce
the loss of water by transpiration. The
green twig (branchlet) now performs the
photosynthetic function of the leaf. It is
cylindrical in cross-section with the stoma
hidden in grooves or ribs to protect them
from water loss.
Photo micrograph of casuarina branchlet showing ribs Photo micrograph showing stomata protected by
and grooves between.
trichomes (hairs) inside grooves.
Photos: courtesy Geoff Burrows.
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23. Adaptations: acacia (wattle)
There is a huge variety of leaf shapes and sizes
as plants have evolved to suit their environment.
The gum leaf is a simple leaf with a blade,
petiole, mid-rib and lateral veins.
Deane's wattle (Acacia deanei) on the right still
has the basic leaf structure but the large surface
area of the blade has been replaced by many
small leaflets.
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The 'leaf 'of the golden wattle (Acacia pycnantha,
Australia's floral emblem) at right is a phyllode
where the original blade has been replaced by
flattening the tough petiole to act as a leaf.
Some acacias have small nectary glands along the
midrib. Ants are attracted to the glands for nectar. The
ants also protect the plan by attacking small herbivores.
This is a symbiotic relationship.
Some acacias such as the varnish wattle (Acacia verniciflua) have a very thick waxy cuticle to reduce
transpiration.
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Above: electron micrograph of the surface of a varnish
wattle phyllode showing open stomata and thick cuticle.
Right: transverse (x-section) section of varnish wattle
phyllode showing cells.
Photos: courtesy Geoff Burrows.
Deane's, golden and varnish wattles are all found in Red Hill Reserve.
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24. Food chains
The movement of energy and nutrients from plant to herbivore to carnivore is termed a food chain. Feeding
relationships are complex and several food chains interconnect to form food webs. Below are plants and
animals found in Red Hill Reserve. Click and drag the images and arrows below the table to make a food web.
Organism
Trophic Level
Organism Trophic Level
plants
primary producer
beetle
primary consumer
chews whole leaf
lerp
primary consumer
sap sucking insect
on gum leaves
cicada
primary consumer
sap sucking on
roots of plants
prior to
emergence
kangaroo
primary consumer
eats grasses
secondary
consumer
eats mainly ants
primary consumer
caterpillar, eats
skeletoniser
green tissue of gum
leaves
galah
primary consumer
eats seeds of
grasses and trees
echidna
possum,
brushtail
primary consumer
eats leaves and
flowers of eucalypts
tertiary consumer
eats other animals
kookaburra
including lizards
and snakes
The more we find out about a particular food
web, the more complex it becomes.
Diagrammatic representations become very
complicated and it is difficult to compare
different food webs. The food pyramid is a
simplified, generalised model of a food web.
The basic pyramid of numbers requires the
counting of all plants (primary producers),
herbivores (primary consumers) and
carnivores (secondary consumers). This
method still has difficulties when comparing
different ecosystems because of the different size of plants or animals. It is partly overcome by using weight
(biomass).
There are different types of pyramids. The layers may show the number of organisms, the biomass (weight) or
the amount of energy at each trophic level. Each method has it's advantages and disadvantages in
representing the flow of energy in an ecosystem.
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Plant biomass represents the
amount of primary production by
plants and is one way of comparing
the productivity of different
ecosystems. Plant biomass
represents the size of the plate of
food for herbivores to eat and so on
down the food chain.
Plant biomass is the
Biomass, world average
weight of plant matter. It
Ecosystem
Biomass (kg/m2)
is usually recorded as the
dry weight of plants in
Tropical rainforest
45.0
kilograms per square
metre of ground (kg/m2). Woodland
6.0
Alpine
0.6
Dark cave
0.002
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25. Herbivory
Leaves are very important because they are the start of the food chain. Without them herbivores and
carnivores would starve.
Estimate the percentage of each of the leaves below that has been eaten by herbivores. Add up the total
damage for the 10 leaves then divide by 10 to get the average damage.
This type of herbivory represents the amount of energy and food passed on down the traditional food chain to
traditional herbivores such as caterpillars. Where does the rest, the vast amount of uneaten food and energy
go?
Task: collect 10 leaves from eucalypt trees in the school grounds and estimate how much of each leaf has
been eaten by herbivores. To be an unbiased sample it needs to be done randomly so select the fourth leaf
from the end of each branch or do it with your eyes closed.
The damage could be whole chunks eaten, brown spots from sap suckers or brown blisters where grubs have
eaten the green part below the skin. Repeat this for an introduced tree or shrub and compare.
Write a short report on your investigation. Include the aim, method, results table and discussion. You might
include in your discussion the impact of introduced species on the food webs of native plants and animals.
What happens to the population of introduced pant or animals if there are no or few predators here e.g. carp,
rabbits or some weeds.
Aim: to compare herbivory on native and introduced plants.
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26. Interactions
Symbiosis (from Ancient Greek sýn "with" and bíosis " living ") is close and often long-term interactions
between different biological species.The symbiotic relationship may be categorised as mutualistic,
commensal, or parasitic in nature.

mutualism where both organisms benefit. Lichens are a a fungi and algae living together. The
fungi provides the structure and the algae photosynthesis food.

commensalism is a class of relationship between two organisms where one organism benefits
but the other is neutral (there is no harm or benefit).

parasitism where one organism benefits and the other one is harmed.
http://en.wikipedia.org/wiki/Commensalism
Allelopathy occurs when organism produces chemicals that influence the growth, survival, and
reproduction of other organisms. These chemicals are known as allelochemicals and can have beneficial
(positive allelopathy) or detrimental (negative allelopathy) effects on the target organisms. Eucalyptus
leaf litter and root exudates are allelopathic for certain soil microbes and plant species.
http://en.wikipedia.org/wiki/Allelopathy
The photos for the quiz below were taken in the Box Gum Grassy Woodland in Kyeamba Traveling
Stock Reserve near Wagga Wagga.
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27. Investigation: kangaroo survey
You are investigating the distribution and number of kangaroos in Pomingalarna Reserve. You survey the
population with a combination of direct sightings by spotlight at night and evidence by way of scats and prints
you have found in sand traps placed along paths.
Below are your results. You have recorded them on an air photo showing the different vegetation
communities. Each picture of a roo represents three roos sighted; each footprint represents two roos and
each scat represents one roo.
Community
Sightings
No.
X3
Prints
No.
X2
Grassland
White box
Red gum
Casuarina
Cypress pine
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Scats
Total
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28. Human impact on Red Hill Reserve
The use of Red Hill Reserve has changed as
community values change. In the early days it had a
utility value and was mined for gold and gravel. The
Reserve is now seen to have biodiversity and
intrinsic values. A community management group
has formed which has obtained government funding.
The group has fenced the reserve to stop vehicle
access, had earthworks done to stop soil erosion and
carried out revegetation projects.
In the early years gold
was discovered at what
is now Pomingalarna
and Red Hill Reserves.
This was reported in the
Brisbane Courier
newspaper in 1924.
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Remains of early gold
workings. Gold was
found in quartz veins
approximately 4 metres
wide running along the
direction of the ridge.
The quartz was
excavated and crushed.
The mine tailings were
later used as road base
leaving little soil, just a
stony regolith with little
vegetation.
Recently there was a
development application
to remove much of the
hill, which is the reserve,
for road base for the
approaches for the new
Gobbagombalin Bridge
over the Murrumbidgee
River.
Local residents formed
an action group which
was successful in
stopping the proposal
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Old explosives storage
sheds and vehicle track
left from the mining
days.
The lack of soil from the
mining days has caused
deep erosion gullies.
The gullies have been
filled and water diversion
banks made to take
runoff away from
problem areas.
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Rocky ground without
soil has been ripped by
bulldozer to shatter the
rock creating a better
habitat for seeds to
germinate and
encourage regeneration
in the Reserve.
Various acacias and
other shrubs are now
growing in and beside a
rip line.

Write a report describing human impact on the original Box Gum Shrubby Woodland that existed on
Red Hill Reserve and how it is being managed today. Use all of the data given in the case study.
Include a location map, references to the abiotic (physical) and biotic (living) features.

What values does the community place on it?

What are suitable uses of the reserve given these values?
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Riverina Environmental Education Centre