Activity 5: Ground layer
Assessing the ground layer in your Namoi ‘special place’
5A
Introduction
A healthy vegetation community needs a healthy ground layer. Looking at the number of
different plants (i.e. the species richness) within an area tells us about the biodiversity of that
area. Native ground cover has biodiversity and environmental value. Assessing the amount of
the ground that is covered by plants, rocks, leaf litter, bare earth and so on provides an
indication of the health of the ground layer.
The plants in the ground layer are important for several reasons; they help to hold soil and
water (preventing soil erosion and decreasing water run-off), add organic matter, help to
increase available nutrients, protect seeds and seedlings, and provide habitat for invertebrates
and small animals. Organic litter (e.g. leaves and twigs) and coarse woody debris on the
ground are also important; they protect seeds and seedlings of native plants, help to maintain
soil condition through microbial activity and nutrient recycling, and provide habitat for native
fauna.
If students are allocated to tasks in small groups, this activity can be done as part of a broader
vegetation survey, combining it with a survey of the canopy and midstorey layers (Activity
4). However, if this activity is undertaken independently of the other vegetation survey
activities, it is a good idea to start with a class discussion that stresses how important it is to
include all layers for a proper assessment of vegetation and habitat.
Aim and outcomes
The aim of this activity is to assess the ground layer of your site. By the end of Activity 5 you
will:

understand the importance of the ground layer

have learnt about the various parts of the ground layer.
Summary of tasks
Timing
Before visiting the
site
(Section 5B)
Task
• Task 5.1 – Ground layer assessment practice
During the visit to
the site
(Section 5C)
• Task 5.2 – Ground layer species richness assessment
After the visit
(Section 5D)
• Task 5.4 – Class discussion
• Task 5.3 – Ground cover assessment
1
Estimated time
Use the accompanying Activity 5 – Record sheet to record the results of the tasks, as
appropriate
5B
Tasks to undertake before visiting the site
Task 5.1 – Ground layer assessment practice
You will need:

a 50 × 20 m plot (see the handout Preparing a plot)

four small hula hoops
or four pre-made 1 × 1 m quadrats that are portable and
reusable (these can be made from four pieces of PVC pipe
cut to 1 m lengths, joined with rope that is knotted at each
pipe end – these are light, and are easy to set up and store
away)
or smart device with Ground Cover app downloaded
http://www.namoi.cma.nsw.gov.au/395590.html

the Ground layer species richness datasheet from Activity
5 – Record sheet

the Ground cover assessment datasheet from Activity 5 –
Record sheet
To prepare for the species richness survey at the site (Task 5.2) students will set up a practice
survey plot within the school grounds. If students are also doing Activities 3 or 4, they can do
this task using the practice plot set up in Tasks 3.1 or 4.1. However, if the class is doing
Activity 5 as an independent activity, students should set up a practice plot, as outlined in the
handout Preparing a plot.
The aim of the practice task is to get to know the features of:

grasses – sheathing leaves with long thin leaf blades, inconspicuous flowers and seedlike grains

herbs – broad-leaved non-woody plants

cryptogams – ferns, mosses and lichens

organic litter.
4 sample photos or
diagrams figure 1,
2, 3, 4
Students will also become familiar with the features they can use to separate the different
grasses and herbs present; for example, leaf shape and size, leaf colour, and whether leaves
radiate out from the centre or are upright.
2
This task does not require students to know plant names; however, they do need to assign
codes to different plants and other features, especially if different individuals or groups are
assessing each quadrat. This should be done before starting to assess individual plots for
species richness within the quadrats. Task 5.2 explains how to set up codes for the different
species and features of the plots.
If the school grounds include areas with different species of ground plants, then students can
practise the procedure they will use when assessing ground species richness and cover in the
field, for Task 5.2. However, if the grounds are uniform lawn, then various objects (e.g.
books, pencil cases and lunch boxes) can be placed into the plot to represent plant forms
(plant species) rocks or bare ground. Students can then use the codes they have set up for
different grasses (G1, G2, G3, etc); herbs (H1, H2, H3, etc); and ferns, mosses and lichens if
present, as shown in Figure 5.2.
Alternatively, students can try the free app called Ground Cover on a smart device. This app
uses the step point method, and describes this simple method.
5C
Tasks to undertake at the site
Task 5.2 – Ground layer species richness assessment
You will need:

two 50 × 20 m plots (see the handout Preparing a plot)

four small hula hoops
or four pre-made 1 × 1 m quadrats that are portable and reusable (these can be made
from four pieces of PVC pipe cut to 1 m lengths, joined with rope that is knotted at each
pipe end – these are light, and are easy to set up and store away)
or smart device with Ground Cover app downloaded
http://www.namoi.cma.nsw.gov.au/395590.html

Ground layer species richness datasheet from Activity 5 – Record sheet

clipboards, extra paper, pencils and pens.
Ground layer species richness refers to the number of different grasses, herbs and cryptogams
(e.g. mosses and lichens) within the ground layer. Students will use trunks, bark, leaf shape
and colour to identify different types of trees within the small plots made using a hula hoop
or quadrat (or using the Ground Cover app), and will record their findings.

This activity uses the transect lines of the 50 × 20 m plots.

Assign student into groups and set up five 1 × 1 m quadrats (using collapsible
quadrats or hula hoops) on alternating sides of the transect line of the plot, at the 10,
20, 30, 40 and 50 m marks, as shown in Figure 5.1.
3
50 m
20
40
1
501
1
1
1
1
30 1
10 1
1
1
20 m
1
1
Figure 5.1. Method for ground cover assessment using 1 × 1 m quadrats (in red) for a single
transect (e.g. Transect 1). Quadrats are positioned either side of the transect tape at
approximately 10 m intervals. The positioning of the quadrats may need adjusting to avoid
shrubs (>1 m) in the shrubby transects.

Fill in the Ground layer species richness datasheet from Activity 5 – Record sheet.
Provide date, site location, group name, transect number assigned (1 or 2), and so on.

The aim is to assess the ground layer species richness. Do not include woody shrubs
of more than 1 m in height. Students can give each different plant (species) a code; for
example, G1 (grass 1), H3 (herb 3), M2 (moss 2), L2 (lichen 2), making notes of plant
features for each code as a reminder. Suggest students use codes for other features; for
example, BE (bare earth), R (rock) and OL (organic litter). These will be assessed
under the ‘ground cover’ section.

Ask the students to go back to the individual 1 × 1 m quadrats of the transect and, on
the sheet provided, record the number of different plants within each 1 × 1 m quadrat.
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Task 5.3 – Ground cover assessment
You will need:

two 50 × 20 m plots (see the handout Preparing a plot)

four small hula hoops
or four pre-made 1 × 1 m quadrats that are portable and reusable (these can be made
from four pieces of PVC pipe cut to 1 m lengths, joined with rope that is knotted at each
pipe end – these are light, and are easy to set up and store away)
or smart device with Ground Cover app downloaded
http://www.namoi.cma.nsw.gov.au/395590.html

Ground cover assessment datasheet from Activity 5 – Record sheet

clipboard, extra paper, pencils or pens, and ruler.

Using the diagram provided on the ground cover (%) worksheet, students will roughly
estimate the ground cover percentage by drawing the area each plant form covers (i.e.
grasses, herbs, mosses, lichens) and labelling with the agreed code, as shown in the
example in Figure 5.2. Remember to include organic litter, rock and bare earth when
calculating cover in the 1 × 1 m quadrats.

For each quadrat, estimate the percentage of the 1 × 1 m area that is covered by
grasses, herbs, mosses, lichens, organic litter, rock and bare ground (bare earth). If
there is a lot of variability within the quadrat, simplify the calculation of percentage
by dividing the 1 × 1 m quadrat into quarters or sixteenths (as shown in Figure 5.2).

Record percentages in the datasheet provided; estimate the percentage of the area
covered by each growth form (e.g. grasses, herbs, cryptogams) within each quadrat
and record in the datasheet.

If present, record the percentage of the area covered by organic litter, and measure the
depth of the litter using a ruler. If litter is abundant over the quadrat, then repeat the
measurement depth five times and calculate the mean (average) value.
Advanced step
Cover percentage could also be calculated for each of the different plant ‘species’ identified
for species richness. Ensure that each group is recording the same data – cover of growth
form (grasses, herbs, cryptogams – or separately as ferns, mosses, lichens) or ‘species’ (e.g.
grass 1) so that replicate data can be combined.
On the datasheet, the five quadrats provide five replicates; therefore, data from each quadrat
will be summed and the mean values calculated.
5

Using data from all quadrats calculate total sum of grasses, total sum of herbs, total
sum of rock, total sum of bare earth and total sum of organic litter.

Calculate the total cover (%); that is, the percentage of the area of each quadrat
covered by plants.

Repeat the calculations for Transect 2, if possible, keeping teams the same.
The number of different native plants versus the number of exotic plants (weeds) can also be
recorded if known – check the plant guide. An extension exercise could be to show the cover
percentage of each different species of plant within the plots, with all groups using the codes
assigned during the species richness exercise. The results from the different sampling
strategies could form part of the overall discussion, asking “Were there differences?”, “If so,
why?” There is no right or wrong answer. Use the questions to extend thinking about what
was observed, and whether the sampling techniques used are detecting differences.
G2
H1
H1
H2
BE
M1
H1
R
G1
Figure 5.2. Example of ground cover assessment in a 1 × 1 m quadrat. There are five
different plants (species) in this plot: herb 1 (H1), herb 2 (H2), grass 1 (G1), grass 2 (G2)
and moss 1 (M1) with bare earth (BE) and rock (R) present. If there is no bare earth, but
the spaces between the plants are filled with organic litter, then this would be recorded as
OL, organic litter. For this plot, the results are: species richness (equals all minus bare
earth minus rock) = 5; cover % estimates, R = 4%, H1 = 15%, H2 = 5%, G1= 6%,
M1=15%, BE = 55%.
6
5D
Tasks to undertake after the visit
Task 5.4 – Class discussion

Question 1: How many different plants formed the ground layer in Transect
1?................................

Question 2: How many different plants formed the ground layer in Transect
2?................................

Question 3: What was the dominant plant form (grass, herb, moss, etc) in Transect 1?
That is, which had the most ‘species’ counts?..........................................................

Question 4: What was the dominant plant form (grass, herb, moss, etc) in Transect 2?
That is, which had the most ‘species’
counts?......................................................................

Question 5: Provide two examples of why the ground layer is important
………………………………………………………………………………………………
………………………………………………………………………………………………
……………………………………………………………………………………………..
……………………………………………………………………………………………..
[Refer to the ground layer introduction.]

Question 6: Why is leaf litter an important part of the ground layer? Provide two
examples
.............................................................................................................................................
……………………………………………………………………………………………..
……………………………………………………………………………………………..
……………………………………………………………………………………………..
[Nutrient recycling – litter breaking down puts nutrients back into the soil;
Fauna habitat – many microorganisms and invertebrates live and break down the leaf
litter;
Retain moisture – moisture is trapped by the mulching effect of the litter.]
7

Question 7: What sort of changes do you think might occur in the ground layer if
there was a fire through the plots?................................................................................
[Depends on the intensity of the fire. If it is a ‘cool’ fire, the above-ground plants and
litter are removed by the fire, but the heat does not penetrate below the surface, so roots,
seeds and microorganisms are protected by the soil. Perennial plants (that grow over
multiple seasons) will re-sprout, and seeds will germinate after rain. The first plants to
grow will be those that are opportunistic (i.e. able to take advantage of newly available
habitat), and grow or spread fast. Seeds of some plants need fire to germinate and
respond quickly after a fire. You might expect that annuals (plants that grow, fruit and die
in one year) would dominate initially after fire, but perennial plants gradually increase. If
weedy species do not have the opportunity to invade, you could expect the area to return
to a similar native species composition as seen before the fire. If the fire is ‘hot’, the
effects would be different, because the heat would penetrate the soil, and regeneration
would be slower and less effective.]
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