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Key Findings of the Banksia Woodland Restoration Project
Mark Brundrett, Margaret Collins, Anna Wisolith and Karen Clarke
Department of Biodiversity, Conservation and Attractions &
The University of Western Australia
1. Introduction to Project and Sites
Objectives of the Banksia Woodland Restoration Project (BWR)
1. Restore and manage banksia woodland
2. Select sites using rigorous ranking process
3. Use scientific approaches to maximise returns
4. Evaluate relative effectiveness of methods
5. Develop monitoring protocols
6. Support community groups and land managers
7. Collate and share information
Commonwealth Government offset for land clearing at Jandakot Airport
Banksia Woodland Monitoring Sites
• 5 Locations in Jandakot and Beeliar Regional Parks
• 31 quadrats for weed control study
• Close to Restoration sites
HarrisdaleSwamp
Rose Shanks
Shirley BallaSwamp
KogolupLake
The Spectacles
Banksia Woodland Monitoring Sites
• 5 Locations in Jandakot and Beeliar Regional Parks
• 31 quadrats for weed control study
• 1 site impacted by fire in 2014
HarrisdaleSwamp
Rose Shanks
Shirley BallaSwamp
KogolupLake
The Spectacles
Weed and Fire Studies
0
5
10
15
20
25
30
35
40
2013 2015 2017 2013 2015 2017 2013 2015 2017 2013 2015 2017
Harrisdale Kogolup Rose Shanks Spectacles
Folia
ge c
ove
r (%
)
Veldt All Dead Veldt Dead on Live
Veldt Live Shrub
Perennial Herb Geophyte
Annual Herb Annual Grass
B Weeds0
5
10
15
20
25
30
35
40
45
50
Folia
ge c
ove
r (%
)
Tree Shrub
Perennial Herb Perennial Grass
Perennial Sedge Geophyte
Annual Herb Annual Grass
Annual Sedge
A Natives
0
20
40
60
80
100
120
0 4 8 12 16 20
Nu
mb
er o
f sp
ecie
s
Month
Seed
Roots
Tuber
Rhizome
Stem
Base
Reseeding
Resprouting
0
5
10
15
20
25
30
35
40
45
0-5 cm 5-10 cm 10-15 cm 15-20 cm 20-25 cm 25-30 cm >30 cm
Ban
ksia
tre
es (
%)
DBH
Resprouting from canopy
Resprouting from trunk
Resprouting from base
Died after resprouting
Died in fire
Weed Study 24 plots Jandakot & Beeliar RPs Fire study Shirley Balla Swamp
Community Grants
• Grants program with $300,000 of funding for banksia woodland restoration by community groups and local governments at 20 locations across the Perth metropolitan area.
Topsoil Transfer Sites
Forrestdale Lake (8 ha)
Anketell Road (40 ha)
Jankakot AirportSite
selection rankings
Restoration Sites
• Sites were weeds-capes before works commenced
• Massive soil seed bank for weeds
• Weedy topsoil was scraped off
2. Reference Site Data for Setting Completion Criteria
• Jandakot Airport Quadrats and Transects
• Tree positions (DGPS) and crown widths on 150 m transects (4)
• Cover and abundance of all spp. from 10x10m plots (12)
• Tree data from 25x25m plots (12)
Relative Importance of Plants
0
200
400
600
800
1000
1200
1400
De
nsi
ty
0
1
2
3
4
5
Pa
ters
on
ia o
ccid
enta
lis
Lyg
inia
ba
rba
ta
Hib
ber
tia
hyp
eric
oid
es
Des
mo
cla
du
s fl
exu
osu
s
Da
syp
og
on
bro
mel
iifo
liou
s
Sch
oen
us
efo
liatu
s
Ph
leb
oca
rya
cili
ata
Da
mp
iera
lin
eari
s
Stir
ling
ia la
tifo
lia
Ca
lytr
ix f
lave
scen
s
Leu
cop
og
on
co
no
step
hio
ides
Pet
rop
hile
lin
eari
s
Styl
idiu
m r
epen
s
Lom
an
dra
her
ma
ph
rod
ita
Co
no
step
hiu
m p
reis
sii
Sch
oen
us
curv
ifo
lius
Hen
sma
nia
tu
rbin
ata
Lep
ido
sper
ma
sq
ua
ma
tum
Lom
an
dra
ca
esp
ito
sa
Co
no
step
hiu
m p
end
ulu
m
Ph
leb
oca
rya
fili
folia
Des
mo
cla
du
s fa
scic
ula
tus
Thys
an
otu
s tr
ian
dru
s
Per
soo
nia
sa
cca
ta
Styl
idiu
m p
ilife
rum
Cro
nin
ia k
ing
ian
a
Arn
ocr
inu
m p
reis
sii
Ca
lect
asi
a n
arr
ag
ara
Ha
emo
do
rum
sp
ica
tum
Laxm
an
nia
sq
ua
rro
sa
Leu
cop
og
on
sp
.
Lom
an
dra
mic
ran
tha
Lom
an
dra
pre
issi
i
Lom
an
dra
su
ave
ola
ns
Thys
an
otu
s th
yrso
ideu
s
Co
ver
Some dominant plants “rescued” for clonal propagation by a specialist nursery
Important Understory Species
Species Rank
Patersonia occidentalis 1
Eremaea pauciflora 2
Lyginia barbata 3
Hibbertia hypericoides 4Amphipogon turbinatus 5
Desmocladus flexuosus 6
Scholtzia involucrata 7Dasypogon bromeliifolious 8
Schoenus efoliatus 9
Phlebocarya ciliata 10
Rank importance values were used to assess the relative dominance of understory plants
Measuring Tree Dominance
• High spatial variability (>0.5 ha survey area needed)
• Over 400 trees / ha in total
• Over 300 banksia trees / ha (main food for Carnaby’s cockatoos)
0
20
40
60
80
100
120
140
160
180
200
De
nsi
ty (
ste
ms
/ h
a)
Use of Reference Site Data in Restoration
Topsoil reference site
Local reference sites
Plant species lists with importance rankings
Existing plot data
Seed collection
targets lists
Direct seeding mix composition
Completion Criteria
Species lists for nursery
orders
Setting Completion Criteria
Criteria Targets
Overall species richness Maximise species richness (not measurable)
Species richness per quadrant Return >60% of native species (10x10m equivalent)
Tree diversity Return all species of trees
Tree density 300 stems/ha for all trees (varies with habitat)
Carnaby’s cockatoo food plants 250 stems/ha for Banksias (in appropriate habitats)
Understorey density Establish 7000 stems/ha (>50% of reference site)
Understorey diversity Return >60% of species
Key understorey plants Monitor 10 most important species separately
*Numeric examples are for Banksia Woodland Restoration Project sites and will need to me adjusted for other habitat types.
3. Comparing Methods for Restoration
Main Restoration Sites
Anketell Road in Jandakot Regional Park
Forrestdale Lake
11.5 ha of Topsoil Transfer in April 2012
Planting
• Over 46,000 plants of 70 species planted
• 3,500 plants of 24 species from cuttings
• Collaborations with Birdlife Austral, Friends or Forrestdale, etc.
Anketell Road
Planted: 32 hectares
Direct Seeding
• Machine seeding was used for broad scale restoration
• Hand seeding was used in areas inaccessible by vehicle
• From 2012-2016 16.5 hectares were direct seeded using 45 kg of seed from 80 different species
Machine seeding
Hand seeding
Anketell Road
Direct seeded: 15.5 hectares
4. Monitoring
• Completion targets (criteria) are based on diversity, density and cover information from reference sites
• Jandakot Airport topsoil source area is the primary reference site, but but some data from local plots was also used
• Monitoring restored areas uses fixed 1x1, 5x5 or 25 x 25 m plots
• Plant diversity, density and cover compared to reference sites quadrat areas of 10 m2 (using 4 adjacent 5 x5 plots)
• The reference site may be atypical (long unburnt, high grazing system)
Adaptive Management Requires Comprehensive Monitoring Data
Reference area species lists with importance rankings
Seed collection targets
Completion Criteria
Species lists for nursery orders and/or direct seeding
Monitoring data quantifying species establishment
Seed collection outcomes
Germination and survival
Plant regeneration from topsoil
Monitoring
5x5 metre quadrats
Total Species Richness
Target Status in late 2015
Maximise native species richness(78 species were present in 12 reference quadrats)
161 native species in total• Highly variable spatially
• Many singletons in plots
Monitoring Plant Density, Cover & Diversity
• Annuals and weeds in 1x1m plots
• Perennial cover in 5x5m plots
• Trees in 25x225m plots
0
2
4
6
8
10
12
14
16
2014Autumn
2014Spring
2015Autumn
2015Spring
2016Autumn
2016Spring
Folia
ge c
ove
r (%
)
Species Area Relationships for Monitoring – Common Plants
• Detection of all plants requires plots to cover the entire area
0
20
40
60
80
100
120
0 2000 4000 6000 8000
Spe
cies
de
tect
ed
(av
era
ge)
Plot area (m2)
All natives
Top 75
Top 60
Top 40
Target
y = 16.84ln(x) - 56.925R² = 0.9671
0
20
40
60
80
100
120
140
160
1 10 100 1,000 10,000 100,000 1,000,000Sp
ecie
s d
etec
ted
Plot size Log m2
Area sampled
Seedling Density in 1 m2 plots• Plot with 39 seedlings of perennial natives (mean = 12, range = 0-42)• Annual native average = 49 (0-163)
Most germinated seedlings died in 2014/15 in driest summer on record
Plant Density
• Stems per ha from 144 - 5 x 5 m quadrats
0
10000
20000
30000
40000
50000
2014Autumn
2014Spring
2015Autumn
2015Spring
2016Autumn
2016Spring
2017Autumn
2017Spring
Pe
ren
nia
l nat
ive
de
nsi
ty
(ste
ms
pe
r h
a)
Anketell Road (topsoil)
Anketell Road (without topsoil)
Forrestdale Lake (topsoil)
Target
Plant Density from Topsoil and Planting
0
2000
4000
6000
8000
10000
12000
2014-A 2014-Sp 2015-A 2015-Sp 2016-A
De
nsi
ty (
ste
ms/
ha)
85 Species
Density of Planted Species Only
0
500
1000
2014-A 2014-Sp 2015-A 2015-Sp 2016-A
Des
nit
y (s
tem
s /
ha)
Planted only (21 species)
Xanthorrhoea preissii Melaleuca thymoides Melaleuca seriata Lepidosperma squamatum SL
Kunzea glabrescens Hypocalymma robustum Hypocalymma angustifolium Eucalyptus todtiana
Eucalyptus marginata Eremaea pauciflora Eremaea asterocarpa Calytrix fraseri
Banksia menziesii Banksia ilicifolia Banksia attenuata Anigozanthos manglesii
Anigozanthos humilis Allocasuarina fraseriana/humilis Acacia saligna Acacia rostellifera
Acacia pulchella
A Complementary Approach
• Topsoil provided high species richness, plant density and many recalcitrant species
• Topsoil alone lacks overstorey species and others with canopy seed
• Direct seeding and planting alone often lacks smaller herbs and annuals
• Thus a combination of methods (topsoil, direct seeding, planting) is most effective
Foliage cover5x5 metre quadrats
0
5
10
15
20
25
2014Autumn
2014Spring
2015Autumn
2015Spring
2016Autumn
2016Spring
2017Autumn
Folia
ge c
ove
r (%
)
Trees
Shrubs
Herbs, sedges and grasses
Restoration Outcomes: Dominant Species
Graph for top 10 native plants by cover. This is dominated by Jacksonia furcellata and Adenanthos cygnorum – disturbance opportunists from topsoil.
Annual plant cover is initially dominated by weeds and Podotheca gnaphalioides, a native disturbance opportunist.
Podotheca gnaphalioides
Jacksonia furcellata
0
500
1000
1500
2000
2500
3000
2014-A 2014-Sp 2015-A 2015-Sp 2016-A
Pla
nt
de
nsi
ty (
ste
ms
/ h
a)
Laxmannia squarrosa
Gompholobiumtomentosum
Scholtzia involucrata
Hibbertia subvaginata
Leucopogonconostephioides
Chamaescilla corymbosa
Jacksonia furcellata
Burchardia congesta
Lechenaultia floribunda
Laxmannia ramosa
Tree Density and Growth
0
50
100
150
200
250
300
350
400
2014 2015 2017
Tree
den
sity
(s
tem
s p
er h
a)
Banksia attenuata Banksia ilicifolia
Banksia menziesii Eucalyptus marginata
Eucalyptus todtiana Other species
0
0.5
1
1.5
2
2.5
2014Autumn
2014Spring
2015Autumn
2015Spring
2016Autumn
2016Spring
2017Autumn
2017Spring
Hei
ght
(met
res)
Banksia attenuata
Banksia menziesii
Eucalyptus marginata
Eucalyptus todtiana
Restoration Outcomes: Perrenial Weeds
Some perennial weeds are common but have low cover (all < 1%).
Annual weeds are more frequent and have higher cover.Anketell Road in 56 - 5 x 5 m quadrats in spring 2015. Red dots show total cover (scale on right).
0
0.2
0.4
0.6
0.8
1
0
20
40
60
80
100
Co
ver
(%)
Fre
qu
en
cy (
%)
Frequency (%)
Cover (%)
Comparing Restoration Potential of Species
Seed quality and germinability determine nursery outcomes
Successful clonal propagation of sedges
Restoration Potential Summary
• Plant diversity is similar (in this case) but vegetation structure differs initially in young banksia woodland on restoration sites
• Long-term trends?
0
10
20
30
40
50
60
70
80
90
0 10 20 30 40 50
Re
fere
nce
sit
e
Restored area
Rank Importance Value Comparison
0 5 10 15 20 25 30
Absent/rare restore
Less restore
Similar
More restore
Only restore
Common Native Plants in Revegetation
• Disturbance opportunists
• From topsoil seed bank
• Decreasing dominance?
• Abundant flowers and seeds
0 5 10 15 20 25 30
Absent/rare restore
Less restore
Similar
More restore
Only restore
Number of Species
Uncommon Native Plants in Revegetation
0 5 10 15 20 25 30
Absent/rare restore
Less restore
Similar
More restore
Only restore
Number of Species
• Low seed or germination
• Resprouting species
• Increasing dominance?
• Clonal Propagation
Restoration Outcomes: Plant Sources
• 160 native plant species by year 4
• Continuum from opportunist to recalcitrant species
113
36
69
22
0
20
40
60
80
100
120
Topsoil Direct seeded Planted Local Opportunistic
Spe
cie
s
Seed Germination and Survival
• Banksia seedling mortality is often high due to invertebrate grazing in winter and severe drought in summer
• Seedlings of most other plants are more resilient than banksias 0%
5%
10%
15%
20%
Direct seeded Cell Nursery Super
Nursery tubestock
Surv
ival
ove
r su
mm
er
Tree Seedling Mortality Rates
• Direct Seeded Banksia attenuata from a 2016 seed germination trial. Deaths from June to October are mostly due to snail and insect grazing and deaths occurring from October to March are due to drought stress.
0
5
10
15
20
25
30
35
40
See
dlin
g d
eat
hs
(% o
f m
ax. e
me
rge
nce
)
Control May
Pre-soaked May
Control June
Pre-soaked June
Winter attrition
Drought deaths
Who is Eating My Seedlings?
• Visible threats to seedlings
0
5
10
15
20
25
30
35
40
1 2 3 4
Caterpillars
KangarooDung
Millipedes
Large Snails
Small Snails
Fenced
Un
fen
ced
The Challenge of Survival
Rainfall deficits 2012-2015
• Several years of planting and seeding are now required to spread the risk of high summer mortality
0
20
40
60
80
100
120
140
160
180
200
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Rai
nfa
ll (m
m)
LTA
2012
2013
2014
2015
2016
Sudden drought in late spring
Outcomes Based on Completion CriteriaCriteria Target
Anketell Roadtopsoil
Forrestdale Laketopsoil
Anketell Roadno topsoil
Total native species richness Maximise native species richness
Total of 160-162 native spp. (highly variable spatially)
71 native spp.
Average native perennial species richness per 10x10m
Return 60% reference quadrats (19 spp.)
30 20 11
Tree diversityPresence of all trees at reference plots
All present
Tree density (stems / ha) >300 243 183 362
Carnaby’s cockatoo food plants (banksias) /ha
250 152 167 222
Average understory species richness per 10x10m
Return 60% of average in reference quadrats (17 spp.)
28(17 – 42)
18(12 – 25)
9(1-18)
Total density of native perennials per 10x10m
Establish 7,000 stems per ha
20,107 6,950 2,675
Annual native plantsNo target set (density is very much lower in reference sites)
17 species4% foliage cover
15 species2% foliage cover
10 species6% foliage cover
Key understory speciesTop 10 most important species from reference plots
All are present, most are common
Not relevant
Weed coverManage serious weeds, especially perennials, monitor annuals
Perennials: 1%Annuals: 4%
Perennials: 1%Annuals: 8%
Perennials: 5%Annuals: 6%
Variability within Sites
Highest native cover: 57% Lowest native cover: <1%
Two quadrats in the same part of Anketell road
Density & Diversity Variations
Density is Lower in areas without topsoil
Diversity is Lower in areas without topsoil
Measuring Area Reaching Targets
• Soil quality issues with Forrestdale Lake limit possible outcomes (buildings and historic land use)
0
10
20
30
40
50
60
70
80
2014Autumn
2014Spring
2015Autumn
2015Spring
2016Autumn
2016Spring
2017Autumn
2017Spring
Pe
rce
nta
ge o
f q
uad
rats
at
targ
et
7,0
00
ste
ms
pe
r h
a
Anketell Road
Forrestdale Lake
Photo Monitoring 1
Spring 2014
Photo Monitoring 2
Spring 2015
Photo Monitoring 3
Spring 2016
Monitoring Total Cover
Ricky Van Dongen & Bart Huntley GIS Branch, DBCA (Anketell Rd)
Downward photos processed for total cover by computer algorithm (eCognition)
5. Sustainable Restoration
Long-term Sustainability & Ecological Functions
Second generation seedlings
Fauna
Pollination
Row 1 - native bees
Row 2 – wasps
Row 3 - flies and butterflies
Row 4 -beetles
Flowering and Seed Set
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
4.50
5.00
0 20 40 60 80 100 120 140
Can
op
y vo
lum
e (
m3
)Basal diameter (mm)
B. attenuata
B. menziesii
Flowering plants
0
20
40
60
80
100
120
140
160
180
2012 2013 2014 2015 2016 2017
Nu
mb
er o
f sp
ecie
s
Flowering
Total
All plantsBanksias
Harmful Ecological Interactions
• Grazing, weed dispersal and parasites of native plants
Pigface is often spread by rabbits and kangaroos
Galls were common on acacias by year 4
Kangaroo grazing was severe in unfenced areas
Summer Drought & Turnover of Species
• Some disturbance opportunists declining by year 5
• More susceptible to severe summer drought
Disturbance Opportunists
• Common plants in restored areas that were uncommon or not detected at Jandakot Airport (a long unburnt site)
Transform: Square root
Resemblance: S17 Bray Curtis similarity
Date12014_Autumn
2014_Spring
2015_Autumn
2015_Spring
2016_Autumn
2016_Spring
2017_Autumn
2017_Spring
2011_Spring
2D Stress: 0.19
Floristic Recovery Trends
• MDS plots of relative dominance using plant cover
No topsoil
Topsoil sourcereference site(Jandakot Airport)Restoration
areas with topsoil
Conclusions I
1. Grazing and control was essential and weed control very important
2. Effective seed quality control and germination treatments were important
3. Comprehensive reference site and monitoring data was required to guide restoration
4. Restoration methods had a major impact on plant cover and diversity and produced different plant community types
5. Banksia trees had higher mortality than most other species
Conclusions II
6. Rapid tree growth, flowering, seed-set and second generation seedlings have been observed
7. Ecological processes such as turnover of species and biological interactions like flowering and pollination are important and need to be studied more
8. Recovery trends vary due to plant functional groups
9. Recovery trends and timing can possibly be extrapolated but long-term monitoring is required
10. Information required for effective restoration of key species needs to be collected and shared
11. Major problems with offset regulation and management occurred during the BWR project
6. Knowledge Gaps & Research Opportunities
Most common request from community groups (Feb 2016):
• Share results and data to help manage native plants in restoration sites.
Data Required for Effective Restoration
• Species lists for restoration sites with:
1. Habitat type (e.g. upland)
2. Soil/hydrology preferences
3. Relative importance of spp.
4. Seed collection/germination issues
5. Flowering and seed dispersal times
6. Restoration potential and issues
7. Animal associations (e.g. Carnaby’s cockatoo food plants)
8. Fire recovery type and frequency
9. Resilience to weeds and other disturbances
10. Susceptibility to pests and diseases
Revegetation Report Card Banksia attenuataFactor Data
Seed Collection 0-101 seeds per tree (average 15), Jan-Feb
Seed preparation Difficult (heat required to open cones)
Seed storage Requires low humidity and temperature
Seed germination High (30-95%), Inhibited by high temperature
Topsoil seed bank No
Direct seeding results Moderate (0-400 seedlings/ha)
Seedling survival (severe summer drought) Low in first year (3-20%)
Tubestock survival (severe drought) Low in first year (10-20%)
Grazing susceptibility High (kangaroos, rabbits, invertebrates)
Growth rates Fast (0.3-1 m/year height)
First flowering > 5 years
Other impacts on seedlings Grazing, parasitic galls, weeds
Restoration Realities
1. Seed collection 2. Propagation 3. Survival
1. Canopy stored seed 1. Germination easy 1. Weed competition
2. Seed easy to collect 2. Seed treatments 2. Poor soil quality
3. Seed collectible in
sufficient numbers
3. Germination slow
and/or erratic
3. Grazing by
invertebrates
4. Seed quality poor 4. Seed viability low 4. Diseases and pests
5. Seed very hard to get 5. Clonal division only5. Grazing by large
animals
6. Viable seed almost
impossible to get
6. Almost impossible to
propagate6. Severe drought
Species related (1, 2) and site specific (3) factors ranked in according to their importance in banksia woodland restoration
top related