Hybridized Control | Biome Studio (MLA, RMIT)

Hybridized Control Exploring the ecological benefits of landscape control

By Sebastian Cocks

Studio Biome Tutor: Alistair Kirkpatrick RMIT Landscape Architecture, Design Research Upper Pool Studio 8 Semester 02, 2021

I acknowledge the Traditional Owners and Custodians of the lands on which I work and pay my respects to Indigenous Elders past, present and emerging. Sovereignty has never been ceded. It always was and always will be, Aboriginal land.

Contents 6. Design Statement 8. Design Statement 10. Northcote Gorge

12. Plant Replacement ID

14. Site Map - Impact of the Urban Context

15. Site Map - Vegetation Conditions

16. Spatial Mapping of Plant Community #4

17. Plant Community #4 Soil Structure

18. Section AA

19. Section BB

20. Key Considerations

22. Hybridized Control | Westfield Reserve

24. Site Analysis

26. Precedent Study 1 | No Mow May

28. Precedent Study 2 | The Picturesque - Rousham House

30. Design Conceptualisation

32. Master Plan (0.5m Contours)

34. Observational Precedents for Core Components

36. Uncontrolled | Swales & Pictorial Meadows

40. Detailed Plan (0.25m Contours) | Protecting the WBPG

42. Semi-Controlled | South African Veld

46. Semi-Controlled | Weed-Suppressing Forest

48. Highly Controlled | Western Basalt Plains Grassland

25. Site History & Budget

56. Video Link & Acknowledgements

“...we are now so deeply implicated in the workings of the Earth system that we really have no choice but to try and design it.”

Richard Weller, We Are Designing the Earth, Whether You Like It or Not

Design Statement Hybridized Control: exploring the concept of landscape control in order to develop a hybridized land management practice with the goal of future-proofing the Western Basalt Plains Grassland ecology.

The notion of control is deeply embedded in the landscape of so-called ‘Australia’. Moreover, control is intrinsically linked with Westfield Reserve as it is the modern-day location of the signing of the Batman ‘Treaty’ in 1835, which saw John Batman manipulate representatives of the Kulin Nation into relinquishing control of these lands. Although Indigenous and English attitudes towards landscape vary drastically; both parties seek a form of control, and the aesthetic result of their landscape management practices is similar.

I don’t pretend that I can make one tokenistic design gesture at Westfield Reserve to undo the robbery of Indigenous land, but this site’s history does beg the question of what level of control is desirable in a landscape – specifically in a public park – and how different forms of control might acceptably help to preserve a diminishing ecology?

The traditional custodians of the site at Westfield Reserve are the Wurundjeri. The Wurundjeri, as with all Indigenous nations, controlled the landscape to improve hunting, gathering, soil and animal health. More importantly, they used forms of control to cleanse and maintain the health of the land. This illustrates the differing concept of land in Wurundjeri culture compared to English – the land’s health is their own, they are the land. Their immense knowledge of the systems involved in the landscape resulted in a large-scale, fine-detailed level of control. “The chief ally (in this control) was fire” (Gammage, 2011, p.2).

The English attitude towards landscape control stems from entirely different cultural values. Traditionally, landscape is associated with wilderness and seen as something that should be dominated. Controlling the wilderness was a symbol of power and status. Nature and humans were separate entities. The English picturesque movement took the desire for control even further by recreating the wilderness in an entirely manufactured way. Picturesque gardens used restricted views to create depth and focussed on boundaries and edge conditions to emulate nature in an aesthetically acceptable way. Traditional English maintenance regimes reflect this domineering form of control.

Westfield Reserve provides a powerful testing ground to experiment with the effects of control by using a combination of First Nations and contemporary land management practices. It is important to note that I am not Indigenous – I am a direct descendant of colonisation. I am exploring the biological processes at play, not presuming that I can resolve the removal of First Nations people from their land. I hope that an increased use of Indigenous land management practices in a culturally sensitive manner will better prepare public parks management in Melbourne for the future of our climate. Specifically, Hybridized Control will act as an incubator for methods of protecting the Western Basalt Plains Grassland against climate change, thus preserving it as an ecology. The Western Basalt Plains Grassland has been selected because it’s endangered, it’s one of only 15 Australian biodiversity hotspots, it’s aesthetically striking, and it encapsulates the threat of climate change to our natural world.

The goal of Hybridized Control is to generate a hybridized regime of land management practices that preserves the Western Basalt Plains Grassland, both in its true form and as part of a novel plant comunity that is better equipped for the extremities of a changed climate. This design intent will be presented through a picturesque framework, which is seen as the ‘ideal landscape language’ and aesthetically aligns with both Indigenous and non-Indigenous landscapes.

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Design Intent Diagram

ard

W

no us

Control of the ‘Australian’ landscape.

el

ler

“We are designing the earth, whether you like it or not.”

City conditions today no longer suit indigenous plants and maintenance techniques.

Avoid this politicised hierarchy - exotics are valid. Develop a land management hybrid that favours plant needs instead of political clout.

Humans are beyond the point of being able to revert the Earth to a ‘natural’ state. We need to design a solution instead.

Control

Humans ARE the landscape, its health is their own.

Landscape is wilderness - the wild needs to be controlled.

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NonInd ige

trol C on

ape sc nd La

Indig eno us La n

Ja m es Hi t

ugh o m ch

Pict

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eA

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ic

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Jo a

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The

Messy ecosystems require framing devices - ecological benefit needs aesthetic presentation.

Hybridized Control: exploring the concept of landscape control in order to develop a hybridized land management practice with the goal of future-proofing the Western Basalt Plains Grassland ecology.

The Picturesque is the ideal landscape language.

Both Indigenous and non-Indigenous groups seek control of the landscape for different cultural reasons.

1835 Batman ‘Treaty’ signed at Westfield Reserve makes this a significant location in the history of the control of this landscape.

I cannot undo the stealing of Indigenous land and subsequent genocide, but Hybridized Control provides an opportunity to investigate the role of control in both Indigenous and non-Indigenous land management techniques.

A hybridization of land management practices is the ultimate goal - Westfield Reserve has the symbolic significance to provide the testing grounds.

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Site Context

Indigenous Nations Boundaries (within Victoria)

This map highlights the spread of the Victorian Volcanic Plain (VVP), which is the area in which the Western Basalt Plains Grassland (WBPG) plant community is found. Only a small part of the VVP falls within the boundaries of the Merri Creek Catchment (MCC), however around one third of the remaining critically endangered WBPG is found within the MCC. Our site is on the land of the Woi Wurrung (Wurundjeri) Nation.

Indig e

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Merri Creek Catchment

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Melbourne Victorian Volcanic Plains (home to the Western Basalt Plains Grassland)

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Woi Wurrung (Wurundjeri)

Key Locations & Summary of the Brief “As our climate intensifies it will become increasingly difficult to establish vegetation in constructed landscapes. Simultaneously, these landscapes will become more important due to increased housing density and potentially reduced capacity of movement, as experienced in the COVID-19 pandemic.”

“The studio’s ambition is to engage with successful planting design in public parks that have minimal maintenance, no irrigation, and minimal budget.”

“How do we achieve greater plant diversity and more engaging and complex design outcomes with reduced maintenance budgets and more hostile climate?”

Mapping of the plant communities at Northcote Gorge will inform a design proposal for Westfield Reserve that addresses the concerns above.

No rt h co te G

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Northcote Gorge Initial analysis of Northcote Gorge - just upstream of our project site - gave insight into the existing plant communities, soil conditions and geological and hydrological systems at play in this part of the Merri Creek.

This area was heavily quarried from the 1840s until the Yarra Bend Park was officially reserved in 1877. The south-western bank of Northcote Gorge – today George Knott Reserve – was backfilled with construction rubble in the 1960s and subsoils from various locations around Melbourne were brought here to create the evenly graduated slope we see today. This post-colonial process of quarrying and then backfilling to create public parkland assets is identical to the history of Westfield Reserve. As such we get great insight into Westfield Reserve’s opportunities and constraints by studying the plant communities and their growing conditions at Northcote Gorge.

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Northcote Gorge | Plant Replacement ID Completing a ‘plant replacement’ exercise for Northcote Gorge encouraged more critical thinking about the growing conditions that preference a given plant’s biological needs - a crucial skill for designing at Westfield Reserve. Below are 20 plants I identified that may have been able to grow in the five identified plant communities at Northcote Gorge.

Suitable Plant Community: #5

Suitable Plant Community: #2

Cupressus macrocarpa Monterey Cypress

Casuarina glauca prostrate Shagpile She-oak

Endemic to California, its ideal growing conditions are full sun - in moist, well-draining soil. I believe this is a type of juniper - they vary in size from a large shrub to a tree. It would be suitable to grow in plant community 5 as it is found here in similar conditions. This spot is roughly north-east facing, remains heavily saturated (due to soil quality?) and grows aroudn the constraints of backfilled geology and stone retaining walls. The tree is growing next to a type of oak and near a major road, showing it can withstand air pollution.

This Australian native grows ideally in sandy or loam-heavy soils in full or partial sun. This small shrub grows in the indigenous section of the garden, directly underneath a conifer. I believe this would make it suitable to grow on the clifftop in plant community 2, where it would outcompete exotic weeds thanks to the impact of the allopathic conifers on the soil. This plant seems to tolerate shade and thin soil.

Suitable Plant Community: #4

Suitable Plant Community: #1

Aptenia cordifolia Baby Sun Rose

Casuarina cunninghamiana River She-oak

This plant will grow in almost any soil conditions as it has a shallow root system - any pH, drainage etc. I believe this creeper would grow suitably in plant community 4. The soil here is full of fine-grained backfill rubble and the aspect faces directly north, with no protection from sun or wind.

The rhizomes of this plant would suit uphill growth where little top soil is needed for shallow root systems. The nature of the plant looks as though it could help stunt the growth of less desirable weeds but covering much of the slope and starving it of sun - helping the novel ecology to function.

This Australian native grows ideally in sandy or loam-heavy soils in full or partial sun, often within proximity of water - usually salt water.

I believe this is a type of sheoak, well-established at Footscray Park.

These trees enjoy wet soil and would have the advantage of being able to reach sunlight by outcompeting the smaller exotic plants currently in plant community 1. The mulch/weed mat formed by its fallen needles and its allelopathy could help reduce the invase exotic specis on site. These trees can grow in poor soil and help to maintain slopes against erosion.

Suitable Plant Community: #2

Suitable Plant Community: #2

Euonymus fortunei Fortune’s spindle

Hardenbergia violacea False Sasparilla

Native to east-Asia this plant, they will grow in most soil types but prefer shaded spots, as shown here. This large shrub/small tree appears in Footscray Park growing underneath a conifer, at the top of the park’s slope. This suggests the plant could do well in plant community 2, atop the cliff. The soil here is better than the thin soil at Northcote Gorge so this shrub would probably be significantly smaller in size.

This flowering climber is native to Australia. It grows best in acidic soils that are well-drained. I believe this is a type of hardenbergia - a native climber. They are hardy and could survive well in the thin soil underneath the conifers of plant community 2. There is even the potential that these climbers could utilise parts of the cliff face if they germinate in its crevices. It could also be used to conceal the fence that protects pedestrians from the steep cliff.

Suitable Plant Community: #4

Suitable Plant Community: #3

Cereus hexagonus Lady of the Night Cactus

This water-adjacent shrub could be established in the riparian zone of plant community 3. It is found here growing with onion weeds which are also present at Northcote Gorge. The plant also is shown to grow well around rocky backfill, which is key to survival in plant community 3. The main question is whether this plant would survive in fresh water river banks or requires the salt levels present in the Maribyrnong (where it is pictured).

Native to Ecuador and Venezuela this cactus likes full sun and low moisture. This cactus grows at Footscray Park next to a date palm, with full sun exposure. This means it would likely survive in the harsh, dry slopes of plant community 4. The soil here contains less backfill so the cactus may take longer to establish at Northcote Gorge and may not grow as large with the root system competing against the construction rubble.

Suitable Plant Community: #4

Suitable Plant Community: #3

Aloe arborescens Candelabra Aloe

This ground cover was pictured growing in full shade, adjacent to a regularly inundated wetlands (Newells Paddock). I think this ability to grow without sun, in wet soil would allow it to establish in plant community 3. It would be hardy and accustomed to high levels of pollution and nutrients due to proximity to the highly polluted Maribyrnong River - giving it a good chance to survive at Northcote Gorge. Again the question of salinity must be raised once this plant can be fully identified.

This aloe is endemic to the southern part of Africa. It is generally found in mountainous areas, rocky outcrops and exposed ridges. This hardy succulent looks like it would easily establish in plant community 4. It grows at Footscray Park in many places that face direct sun and wind exposure, often found alongside large date palms. It seemed to have a shallow root system and grows well within stone-edged garden beds so it would likely survive in the rubble backfill at Northcote Gorge.

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Northcote Gorge Plant Communities

Suitable Plant Community: #1

Suitable Plant Community: #4

Melianthus major Giant Honey Flower

Aloe maculata Soap Aloe

This medium-sized shrub (<3m) is native to South-western Africa and has become a weed in Australia due to the suitability of growing conditions. It likes full sun and moist soil, pH is not necessarily important. It would be suitable to plant community 1 where it can be kept under control by the groundskeepers and mulched in winter to avoid frost.

This aloe is native to South Africa. It is very salt and drought tolerant, it grows well in seaside and rocky mountainous areas. I believe it would grow well in the thin soil atop the cliff in plant community 2.

Here the aloe would not be upset about the lack of moisture and presence of basalt underneath the top soil layer. It would also form a barrier for the clifftop and provide aesthetic flowering in spring.

Suitable Plant Community: #2 or #5

Suitable Plant Community: #5

Helleborus orientalis Lenten Rose

Laurus nobilis Bay Tree

This small shrub - native to Greece & Turkey - grows best in shaded areas in moist, well-draining soil. I believe this would be most suitable for plant community 2 or 5 where the exposure is not too sever, but the soil is not silt-based and regularly flooded.

The Bay Tree is a large shrub, but it can grow into <20m tall trees.

This tree is endemic to the Mediterranean and can grow in Oceanic climates. The tree is slow growing, likes full or partial sun and moist, well-drained soil. This seems most suited to plant community 5.

Suitable Plant Community: #4

Suitable Plant Community: #1 or #3

Ficus macrophylla Moreton Bay Fig

Fatsia japonica Paper Plant

This large tree is native to Australia. It has a large, vigorous root system in the right conditions. I believe it would grow best in plant community #4 where it would recieve heavy sun and stand a chance of penetrating the layer of fill underneath the top soil with its powerful roots. The extensive roots would also help to anchor the soil here from eroding.

This large shrub grows best in acidic, well-drained organically rich soil. It likes to be protected from sun and wind. I believe it would grow well in plant communities 1 or 3, in the most shaded areas that are richest in nutrients from regular flooding.

Suitable Plant Community: #4

Suitable Plant Community: #5

Roldana petasitis California Geranium

Leucadendron salignum Common Sunshine Conebush

This large, soft-wooded shrub is native to Mexico and Central America. This perennial like dry soil and will regrow from its base when killed by cold or pruning. I believe it would suit plant community 4 due to the less harsh sun and hardy ability of the plant to regrow if beaten by harsh winds.

This evergreen, woody shrub is native to South Africa. It is very drought tolerant, likes sun and sandy-acidic, well-drained soils. I believe it would grow best near the top of the running track in plant community 5 where is can withstand the harsh conditions. Here the plant would be least likely to encounter phosphorous fertiliser which it doesn’t like - this may be an issue closer to the creek from industry runoff.

Suitable Plant Community: #5

Suitable Plant Community: #2

Hesperoyucca whipplei Chaparral Yucca

Kalanchoe beharensis Felt bush

This species of yucca is native to southern California and Mexico.

It grows dry, clay heavy soils in full sun. It is quite difficult to grow outside of its native range, but I believe the heavy sun and sloped drainage of plant community 5 would allow it a chance to thrive. It can be used in medicines, food and as a form of cloth.

This is a succulent shrub from Madagascar that can become treelike, growing up to 3.5m tall.It likes partial shade and is not particularly fussy about soil conditions as long is there is sufficient drainage. I believe it would grow well in the thin soil of plant community 2, protected from the harshest sun by the taller conifers.

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Northcote Gorge | Site Map - Impact of the Urban Context 1:1000 @ A3

This layered map of Northcote Gorge shows the urban impact on the site. Important takeaways here are the presence of 1960s construction fill in the geology and the pollution and nutrient levels of the soil cause by the creek.

These conditions are identical at Westfield Reserve and will influence any planting there, especially by the creek-edge. It will be interesting to see if the plants that survive in the polluted soil of plant community #3 will also appear at Westfield Reserve in my swales, which will be saturated by street runoff. Using construction fill as a contour manipulation is a very European form of landscape control that will be adopted in my design for Hybridized Control.

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Plant community Merri Creek

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Topsoil depth Cliff face Fill in soil structure

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Runoff pollution

Northcote Gorge | Site Map - Vegetation Conditions 1:1000 @ A3

This layered map illustrates the vegetation surrounding the creek and its conditions. Most plant communities here are novel ecologies, they represent the plants that arrive here by chance and survive in these conditions. This begs the question of what changes and subsequent control techniques may be implemented to privilege my chosen plant communities.

It is interesting to see the clustering of shrubs and lack of trees in front of the cliff-face, most likely this is due to the flooding and highly silty, poor-draining soil in this area. I wonder if the ha-ha I implement around my grassland will trap moisture and develop a similar ecology at a smaller scale?

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Soil moisture 15

Northcote Gorge | Spatial Mapping of Plant Community #4 1:1000 @ A3

Mapping the spatial layout of the plants in community #4 illustrated the role the fill is playing.

The slope seems to drain differently to a natural hill as the largest vegetation is at the summit, which would presumably have the lowest moisture content. This could be explained by the relative lack of fill here compared to the foot of the hill. It is important to understand the impact of the fill as Westfield Reserve was also filled with construction rubble upon closure of the basalt quarry there.

The fennel clearly concentrates at the foot of the hill, this is also where the majority of dead grass is. Most of the grass - Pennisetum clandestinum - is dead because it is growing so vigorously that the bottom layer is blocked out of sunlight. I think the thermal mass of the fill here is also drying out the soil. It will be interesting to see if I can use these tools to privilege native grasses over exotic species without the need of heavy maintenance in Westfield Reserve.

Pheonix canariensis Oxalis flowers Clusters of yellow flowers from the Oxalis obtusa gather at the top of the site in the brightest sun exposure.

Dead grass

Fennel dead heads The fennel dead heads vary in size and are spread widely across the plant community. They concentrate towards the foot of the hill, perhaps enjoying the relatively higher moisture and nutrient levels.

The palms are stunted here despite the relative density of large trees surrounding them. This suggests that the top soil is very thin because these palms depend on their secondary root system near the surface to grow the eucalypts with deeper, stronger roots are managing to grow in the construction rubble fill.

Rocks (from fill) Topsoil has eroded to fully expose the 1960s construction fill in some areas. The rocks here act as a natural mulch - blocking sunlight, trapping moisture and generating thermal mass - affecting vegetation survival.

The dead grass (Pennisetum clandestinum) seems to concentrate around the exposed fill and the footpath. Presumably this is cause by the thermal mass of the rocks/footpath and the lack of moisture here in the exposed soil.

Fennel dead heads Pheonix canariensis Various eucalypts Oxalis flowers Rocks (from fill) Dead grass Living grass 16

Northcote Gorge | Plant Community #4 Soil Structure 1:10 @ A3

The detail for the soil structure of Plant Community #4 shows the impact of the fill on stunting the palm’s growth. We can also see the small-scale nature of the novel ecology here. Given the artificial construction of this slope, presumably these plants were not planted and have all arrived here by themselves. It will be interesting to see what conditions are needed to change in my semi-controlled areas at Westfield Reserve to alter this plant community or prevent it from arriving all together.

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Pheonix canariensis

Even Slope Gradient

The palms are stunted here despite the relative density of large trees surrounding them. This suggests that the top soil is very thin because these palms depend on their secondary root system near the surface to grow.

The tap root that pushes vertically down is struggling to find nutrients and moisture in the underlying artificial geology as it is full of porous rubble.

As the underlying geology is artificially made, the slope here is very even. This results in fairly evenly spread vegetation horizontally across the slope where moisture is at a desirable level.

Foeniculum vulgare

Topsoil The topsoil is very thin (around 30cm - 60cm deep), resulting in predominantly small, shallow-rooted grasses and forbs. It would be slightly thicker towards the bottom of the site where gravity pulls. Pennisetum clandestinum covers the site, meaning very little light hits the soil underneath.

Found at the bottom of the slope with richer, moister topsoil. They presumably washed here from agricultural runoff upstream or in neighbouring gardens. Could also grow coriander in these conditions.

Humus A thin layer of decomposing organic matter is found underneath the grasses and forbs. This layer is less rich than other more densely vegetated parts of the Gorge.

Subsoil The subsoil here was brought in after the construction rubble to create the slope surface, it comes from various locations around Melbourne. It would be a mixture of fine-grained rubble and decaying organic matter, meaning the pH level and moisture retention could vary quite a lot. This could explain the lack of mid-storey shrubs here - only forbs and grasses grow in the topsoil and large trees grow as they can survive in the construction rubble.

Malva silvestris Mostly found in the exposed, top of the slope as there is thin soil and little competition.

Underlying Geology

Construction Rubble The form of the slope was artificially created with construction fill in the 1960s. Presumably this fill consists of glass, terracotta, concrete, steel, stone, timber and possibly some plastics. The concrete would increase the pH as it breaks down, which would make for an alkaline soil, especially when combined with the basalt underneath.

Underneath the 1960s construction fill would be a layer of richer organic matter from the previous surface topsoil level. Under this is the alkaline basalt (at around 10m depth) and then sedimentary siltstone further down.

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A

Northcote Gorge | Section AA 1:500 @ A3

A

In section it is easier to see the impact of the fill upon the roots of the vegetation. The Canary Island Palm is stunted because its ability to grow from a secondary root system near the surface is restricted by the artificial fill. Where the fill has become exposed through the topsoil it is acting as a form of mulch - retaining moisture, blocking sun and heating up the soil through thermal mass – this was incorporated into the design for Westfield Reserve.

Topsoil Subsoil Construction fill Previous topsoil

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Basalt

Malva silvestris

Pheonix canariensis

Foeniculum vulgare

Mostly found in the exposed, top of the slope as there is thin soil and little competition.

They are showing stunted growth - presumably because they are fairly young, the secondary root system has shallow subsoil, confined by the fill underneath. Could replace these with Bismarck Palms that like the dry, well-drained soil.

Found at the bottom of the slope with richer, moister topsoil. They presumably washed here from agricultural runoff upstream or in neighbouring gardens. Could also grow coriander in these conditions.

Eucalyptus

Ulmus procera

10% of the root system is near the surface.

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3

1

Appears to concentrate near the creek-edge - presumably for water. It spreads through prolific suckering - this whole bank could technically be one ulmus.

Could replace with Zelkova serrata.

Topsoil Thin layer (~60cm) of topsoil, thicker at the bottom of the slope and around the exposed rocks due to gravitational pull.

Subsoil

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Exposed Fill Exposed rocks from the underlying fill act as a mulch, trapping in moisture and heat and blocking sunlight.

Rubus plicatus

n t Su

Spread up the slope, concentrates in the pockets of thickest topsoil. Could replace with Cotoneaster adpressus, a Chinese climber that likes similar aspect and moisture conditions.

Flood-Tolerant Roots All the plants in PC3 have either strong root systems or the ability to grow from cuttings as an adaptation to flooding.

From various locations around Melbourne - artificially filled.

Fraxinus angustifolium Tradescantia fluminensis

Wind

Fill

Salix fragilis

The slope up to George Knott Reserve was human-made using construction rubble in the 1960s.

This makes for a very even gradient. I presume the larger pieces of fill are used to create the higher eleveations and the fine-grained fill has washed to the bottom of the slope.

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Basalt

Sand/Silt Topsoil

Solanum nigrum

The underlying geology of the site is alkaline basalt. Underneath this is sedimentary siltstone.

The topsoil in PC3 is high in nutrients and pollutants from creek runoff. The subsoil washes away.

Short-lived, which is good for flood-zones. Prefers drained soils so growth is stunted (<1m) to shrubbery. Could replace this with Lycium barbarum (Goji Berry) to generate revenue as it tolerates high nitrogen.

Rampant - grows all over the site. Perhaps thickest at the creek-edge as it grows from broken stem pieces that may concentrate here.Smothers other plants. Likes the moist soil.

Cleared/managed at the top of the site. Could replace with a native orchid such as Zeuxine oblonga.

Northcote Gorge | Section BB 1:500 @ A3

The other important takeaway from the sections at Northcote Gorge that are illustrated in Section BB are the ways in which the vegetation spreads. The vegetation that is near water has adapted to spread by suckers or cuttings to survive floods. Plant community #2 shows that indigenous plants like thin, nutrient-poor soil and may be aided by allelopathic qualities of conifers. I could create an allelopathic barrier to aid native species in Hybridized Control. Pennisetum clandestinum is one exotic species that thrives but will ideally be controlled as it can dominate smaller species and may prevent the spread of native forbs and grasses. We also want to avoid aiding the pread of Fraxinus angustifolium or Salix fragilis in any way as they are a massive threat to Victorian waterways.

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Vinca major

Allium triquetrum

Quercus robur

Even distribution across the site as it likes both sun and moisture.

It climbs easily and has shallow roots. Could replace with Alstona macrophylla as it tolerates similar climate, but the root system is not as vigorous.

Denser at the bottom of the site, where water is drawn. Its fine root system does not have to compete with the large, thirsty Quercus. Could replace with Clivia miniata as it likes semi-sunny, moist positions of similar aspect.

Found at the bottom of the slope where the topsoil is thickest and moisture is highest. The fact that this Quercus is the only one of its size in a riparian zone indicates regular flooding that it has been lucky to survive - it is a very mature tree.

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Allelopathic Conifers

A sheer cliff exposes the basalt rock geology. The topsoil in plant community #2 atop the cliff is very thin.

Conifers such as those found at the top of the cliff are alleopathic - they chemically alter the soil in a way that makes it difficult for many exotic plants to grow, favouring indigenous species.

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Topsoil

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he ars

Thin layer (~60cm) of topsoil, thicker at the bottom of the slope and around the exposed rocks due to gravitational pull.

2 Bursaria spinosa

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Fill The slope up to George Knott Reserve was human-made using construction rubble in the 1960s.

This makes for a very even gradient. I presume the larger pieces of fill are used to create the higher eleveations and the fine-grained fill has washed to the bottom of the slope.

Basalt Cliff

st S

un

Rhizamotous and smaller when not near the coastline (~2-5m). It grows in clumps and likes higher altitudes. One would expect to find it near clifftop walks as it is very commonly used as a barrier.

Clematis mycrophylla

Elements

W ind

Buffers

A climber, it descends the rocky cliff face and grows in pockets of topsoil. Could replace with shade-loving Helleborus niger at the base of the cliff.

Wind Pennisetum clandestinum

Previous Topsoil

Rampant over the site. Would be denser at the creek-edge/base of the cliff where maintenance cannot eliminate it.

Underneath the construction fill will be a layer of organic matter from the previous topsoil.

Basalt

Fraxinus angustifolium

Salix fragilis

The underlying geology of the site is alkaline basalt. Underneath this is sedimentary siltstone.

This plant is a major problem in Victorian riparian zones. It loves the nutrient-rich soil and grows prolifically by suckering. It eventually forms a monoculture that supresses native species.

Very brittle - it spreads by growing roots from broken branches that lodge in riverbanks. It is a major problem in Australian waterways as it grows rampantly in water, causing blockages and displacing water currents (which causes erosion).

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Northcote Gorge | Key Considerations These are the four key considerations I will take from analysis of Northcote Gorge to implement in my proposal for Hybridized Control at Westfield Reserve.

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1. Predicting Novel Ecologies

2. Impact of Exposed Rock

Northcote Gorge shows the novel ecologies that ‘naturally’ form in soil that is regularly inundated with nutrient-high and polluted water. This predicts the plant communities that might form in the uncontrolled zones of Hybridized Control - chiefly in the runoff-catching swales.

We can see the ways in which exposed rocks act as a form of mulch. They trap moisture, block sunlight and generate thermal mass. Hybridized Control will employ this in the Western Basalt Plains Grassland.

3. Allelopathic Trees

4. Suitable Plant Identification

Allelopathic trees create a chemical imbalance in soils that preferences native plant species over exotics. This will be used to create a protective barrier for the Western Basalt Plains Grassland that is free of rampant exotics.

Plants that were identified in the Plant Replacement ID exercise will be used for suitable plant communities in Hybridized Control. This research formed a database of plants that grow in similar conditions to those found at Westfield Reserve.

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Westfield Reserve | Hybridized Control Analysis of the conditions at Northcote Gorge prepared me with an understanding of this area’s geology, history and ecological systems. I was then able to start placing Hybridized Control onto site at Westfield Reserve.

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Westfield Reserve | Site Analysis There are several influential factors highlighted by site analysis of Westfield Reserve. Firstly, it is important to note the central sun-baked grassy area - this could become a great central social point. Secondly, we have to consider the scale of the streets that border our site, especially Heidelberg Road. These will create a lot of toxic runoff, noise and are the main source of passing interest in the site. We should also note the types of trees present, especially the conifers with allelopathic qualities and the eucalypts that may benefit native species. The movement of people also influenced Hybridized Control by directing the placement of mown highway passages. The constraint of the riparian plant community along the creek that is managed by the Friends of the Merri Creek must also be considered.

Existing Management Area

Sunny Central Focal Point

Existing Trees

Busy Adjacent Streets

The area already managed by the Friends of the Merri Creek will be difficult to change for political, cultural and social reasons.

The centre of the park is exposed for full sun. It will provide a good focalpoint and social gathering space.

The existing trees provide a large constraint. They will be expensive to remove and may provide allelopathic and aesthetic benefits.

The adjacent streets are a large constraint. They will produce polluted street runoff and noise. They also generate passing interest in the site.

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Westfield Reserve | Site History & Budget Parameters The site’s history is closely entwined with the notion of control due to the signing of the 1835 Batman ‘Treaty’ - thought to have taken place along the banks of the Merri Merri at roughly this location. The treaty saw John Batman claim the lands of the Kulin Nation by coercing Wurundjeri representatives into signing a document written in English legal jargon. The gesture was misinterpreted by the Indigenous people as the foreigners asking for permission to cross the land, the reason for local Aboriginal acceptance. The ‘treaty’ was swiftly declared invalid, however control had already passed. This gives the site significant symbolic power in our investigations into control over the landscape.

The site also shows great malleability as a landscape. It has changed from the original woody grassland EVC, into a basalt quary, and was then backfilled and turned into mown English-style parkland. This gives a lot of flexibility to potential design iterations.

It is important to note how an progressively more fraught climate will impact the site conditions. The site already receives very little rainfall (~600mm p/a) - we can expect this to decrease and become less predictable. Temperatures will polarise, meaning hotter, drier summers and colder winters. Acid rain and other extreme weather events will also damage the environment and impact soil toxicity.

The City of Darebin’s budget for 2021-22 only allows for two days per month of three maintenance workers on site (assuming the budget is spread evenly across all green space within the council boundaries). This means that we need to design plant communities that require very little ongoing maintenance and can withstand a very harsh climate. Maintenance techniques that are more intermittent will be more practical give our tight budget - controlled burning every few years seems a sensible solution.

Westfield Reserve Total area = 7.1ha

= 1.18% of total green space under council control.

1.18% of total budget = $17,743.65

= 591 total hours of labour @ $30p/h

= 74 x 8 hour days of labour

= 3 workers on site every 14.79 days

City of Darebin

This means our design should only expect to have maintenance workers attending twice per month. This gives a sense of the need to reduce the maintenance requirements of the design.

Total green space: 600ha Total budget allocated: $15,037,00.00

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Precedent Study 1 | No Mow May From May in 2021, seven out of 10 English councils committed to an initiative to reduce mowing of public grass areas – this has now been formalized into ‘No Mow May’. Southwark Council in London has mowed one third less grass area than previous years. This has allowed swathes of wildflowers to sprout from existing soil-stored seedbank. The intention of the stop in mowing is to allow grasses to grow longer to provide habitat for wildlife. In particular, insects rely heavily on the shade and moisture created by the longer grass.

There are several other benefits of the unmown. Firstly, there is the reduction in maintenance costs – a crucial factor in assessing the success of the design proposal for Hybridized Control. As is shown in London parks that have not been developed on for over 100 years (such as Peckham Rye common) there is a wealth of soil-stored seeds that produce aesthetically attractive flowering plants. Westfield Reserve’s soil conditions have not been changed in over 50 years, and it is safe to assume that many attractive plant seeds have entered the site. It would be visually interesting, financially practical, and environmentally friendly to leave this site unmown and see what biodiversity is lying dormant within the soil.

This precedent is important in predicting the aesthetic impact of stopping mowing at Westfield Reserve in the uncontrolled zones of Hybridized Control. It also provides crucial theoretical framework to justify this decision, and gives a social cause to which the design can be attached to soften its impact on the community.

Unmown

Mown

1. Requires annual slashing at the end of summer (rake away cuttings to reduce soil fertility)

1. Reduces the shelter available to insects

2. Shade and mositure is trapped within the longer grass, creating a habitat for insects 3. Soil-stored seeds produce plants that may flower and replenish the soilstored seedbank 4. Reduced maintenance cost 5. Increased aesthetic diversity 26

Stopping mowing also generates spaces that can experiment with the framing conditions that render messy ecosystems presentable. Ultimately these are spaces that need to be enjoyed by people, as well as provide environmental benefit. Environmental sustainability has never been more in vogue, but it is still necessary to make these unmown areas palatable in some way. Hybridized Control provides a landscape to experiment with the aesthetic, environmental and financial benefits of unmown novel ecologies, while also testing the edge conditions necessary for presenting this. It is important to bring the aesthetic power of messy ecosystems into the city, where people may not be able to view it otherwise. Engagement with the pictorial meadows generated by reduced mowing creates empathy for the plant community and begins the process of social investment.

6. Increase plant biodiversity

2. Doesn’t allow for plants to grow/generate biodiversity 3. Costs money 4. Creates a cue to care - a palatable edge condition/framing device

“We must design to frame ecological function within a recognizable system of form” Joan Nassauer, Messy Ecosystems, Orderly Frames

Mown Highways Frame Pictorial Meadows A photo taken from Plantlife’s ‘No Mow May’ campaign shows the aesthetic potential of reduced/more considered mowing. The meadow is simply allowed to grow for longer, then a walkway is mown. This technique will be employed to generate and frame my uncontrolled zones in Hybridized Control.

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Precedent Study 2 | The Picturesque - Rousham House Rousham House in England is used as a precedent to illustrate the aesthetic framework employed by the picturesque movement that shaped British country manors in the 18th century.

The picturesque movement stemmed from an English desire to break away from the formality of baroque 17th century design, which was associated with France. The manor’s designer, William Kent, employs undulating landscape, surprising viewpoints and scattered sculptural and architectural reliefs – traits that come to define the picturesque movement.

The picturesque is an important stylistic precedent as is is often referred to as the ideal landscape language in the Western world. Joan Nassauer writes in Messy Ecosystems, Orderly Frames that “Nature has come to be identified with pictorial conventions of the picturesque”.

This is because the picturesque style presents ‘nature’ in a way that is heavily manicured and contorted to appear controlled. This creates cues to care that are essential pieces of evidence of human influence - which is what users seek in a landscape.

Rousham House is successful in that the extended views evoke the sense of being part of an ongoing garden-scape. This aim is achieved through the use of the ha-ha, which encloses a property without disturbing view lines. Rousham also highlights the impact of Newtonian natural philosophy on landscape design. Newton’s investigations into space and gravity created a desire to explore limitless space and to embrace interactions with nature. This resulted in using expanses of lawn rather than gravel pathways to encourage visitors to interact with their immediate natural environment while walking. The architectural reliefs employed at Rousham House serve to manipulate views to create a sense of depth. Though seemingly ‘natural’, picturesque view lines are very intensely curated to create an illusion of wilderness.

The other significant reason for studying the picturesque is the way in which it alignes with descriptions of Indigenous landscapes across Australia upon the arrival of Europeans. The European colonisers described the environment they entered as like an English ‘park’. They described the generous expanses of grass beneath sparsely dotted trees. In some locations the Indigenous custodians of the land even planted avenues of trees to direct routes of travel. All of these descriptions, as well as first-person evidence in the form of paintings done by Europeans upon arrival, illustrate the aesthetic similarities between the picturesque style and the landscape produced by thousands of years of First Nations occupancy.

1. Ha-ha Wall

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The ha-ha is a framing device used in the picturesque to enclose a property without interrupting views. It will be employed in Hybridized Control with the added benefit of blocking seed movement and controlling fire.

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2. Extended Lawn Sight Lines Spaces within the grounds are joined with expanses of lawn, rather than gravel or hedged formal passages. This encourages interacting with nature while moving.

This is why all passages in Hybridized Control will remain grassy.

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3. Depth-Generating Architectural Reliefs

Plan for the grounds at Rousham House by William Kent.

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This shows the implementation of sparsely dotted tree clusters and serpentine walkways. These are all tools used to recreate a feeling of ‘nature’.

Architectural reliefs were intentionally placed at the ends of lines of view to draw attention. This emphasised the depth of the line of sight by highlighting the furthest point.

Mount Lofty from the Terrace, Adelaide | Martha Berkeley (1840)

Water at Wentworth, Yorkshire | Humphry Repton (1803)

Comparing Indigenous-Controlled Landscapes with the Picturesque The left-hand image above shows a European depiction of an Australian landscape around the time of European arrival in 1788. The right-hand image is a painting of an English manor estate.

Both landscapes have aesthetic similarities. Trees are sparse, dotted in a vast open grassy plain.

Theonly place where trees are allowed to grow more densely is atop hills or mountains. This picturesque aesthetic is described as the ideal landscape language by Joan Nassauer, and will be used to frame the design for Hybridized Control

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Hybridized Control | Design Conceptualisation To conceptualise Hybridized Control I created a heat map of levels of control to divide the site. It starts with a central focal point that is highly controlled, to act as a social gatheringspace with clear cues to care. Control wanes from this point outwards. Adjacent to the high-control centre will be semi-controlled zones, and then the edges of the site will be uncontrolled. These zones are then refined by the main routes of pedestrian movement, which must be controlled to allow safe and pleasurable passage. The pedestrian passages act as the framing device to give our less controlled zones their appropriate ‘cues to care’ (Nassauer, 2007). The riparian ecology along the creek edge will be uncontrolled as it is already managed by Friends of the Merri Creek.

Control Mapping Diagram

1. Control fading out from the central point

2. Adding the creek area that I cannot control

3. Key pedestrian routes cut the map into zones

Levels of Control Existing Management Area

Uncontrolled Zones

I will not try to assert control over the area already managed by the Friends of the Merri Creek as they have jurisdiction.

Semi-Controlled Zones

The edges of the site will be uncontrolled to see how the urban runoff affects them and allow space for novel plant communities to form.

Controlled Pedestrian Walkways

Spanning from the highly controlled centre will be semi-controlled zones which are shaped by the pedestrian passages and uncontrolled areas.

Routes of pedestrian movement will be controlled to encourage pleasurable movement through the site.

Highly Controlled Centrepiece At the exposed centre of the park will be a highly controlled plant community to act as a social and biological centrepiece.

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Hybridized Control | Master Plan (0.5m Contours) The control heat map and the zones it generated were translated into site manipulations, shown below on the master plan.

The uncontrolled zones will have swales excavated to ~1.5m depth adjacent to the street.

These catch street runoff to protect the other plant communities and explore what species survive in novel ecologies with these conditions. The areas between the swales and the pedestrian highways will be unmown pictorial meadows. Their inner borders will be framed with contour banks to help contain seeds and act as a potential fire break.

The semi-controlled zone immediately north of the Western Basalt Plains Grassland (WBPG) is a weed-supressing forest. It is designed to protect the WBPG by supressing the growth of rampant exotic species in this area. In doing so, wind-blown seeds are prevented from entering the grasslands on the hot northerly winds of summer. Weeds will be supressed by implementing a planting schedule of plants with both physical and chemical weed-killing properties.

The semi-controlled zone south-west of the WBPG is a South African veld (open grassland) set up to emulate the harshness of our future climate with dry, nutrient-poor, hot soil. This veld will catch the wind-blown seeds of the WBPG in summer to try and generate a novel plant community combining the two ecologies. Potential genetic hybridization may also occurr with some WBPG species that are highly adaptable and can live in hotter, drier climates, such as Themada tiandra or Ptilotus.

The WBPG is the central focal point of the design. It will be retained in its pure form within the ha-ha and allowed to mix with other plant communities outside of this. It will be constructed as an oval mound with varied soil structures to encourage a mix of grasses and forbs.

The pedestrian highways will be regularly mown as a cue to care for users. This gives the potentially messy ecosystems we are generating a necessary framing device. These also play into the picturesque principles of view lines.

Core Components 1. Highly Controlled | Western Basalt Plains Grassland

2. Highly Controlled | Pedestrian Highways

The centre is a segregated Western Basalt Plains Grassland. It is retained in its pure form and allowed to blow seeds into the South African plant community to form a novel plant community.

The key pedestrian routes of movement will be mown highways. This creates the required framing for the otherwise messy plant communities. It also taps into the picturesque theory of sight lines.

3. Semi-Controlled | Weed-Suppressing Forest

4. Semi-Controlled | South African Veld

North of the WBPG is a forest that supresses ‘weeds’ using allelopathy and mulch-forming conifers. Weeds are controlled here to stop them blowing seeds into the WBPG on summer winds.

South of the WBPG is a South African veld (grassland) set up to grow in harsh soil conditions to emulate our future climate. Seeds will blow here from the WBPG to form a novel plant community.

5. Uncontrolled | Swales

6. Uncontrolled | Pictorial Meadows

Swales are dug in these locations to catch street runoff. This protects the rest of the park from some pollutants and provides exploration into pollution-tolerant novel ecologies.

The areas between the swales and pedestrian highways will simply be unmown to generate a pictorial meadow. This increases insect habitat and illustrates the soil-stored plant biodiversity.

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Hybridized Control | Observational Precedents for Core Components A collection of observational precedent photos to visualise the core elements of Hybridized Control. The photos illustrate the differing levels of control and some of the intended plant communities, such as the uncontrolled swale novel ecology, the semi-controlled She-Oak forest and highly controlled grassland. Some precedent framing devices and edge conditions are also given, including photos of how Hybridized Control intends the mown highways to appear.

Uncontrolled Zones & Edge Conditions

Semi-Controlled Zones

Highly Controlled Zones

Mown Pedestrian Highways

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Uncontrolled | Swales & Pictorial Meadows The three uncontrolled zones consist of a trenched swale adjacent to the street and an inner pocket of pictorial meadow, framed by a contour bank.

The swales are dug to ~1.5m depth parallel to the streets to capture runoff. This serves to protect other plant communities from polluted water and wind-blown seeds, as well as creating a highly pollutant-tolerant novel ecology. This is important as it visualises the plant species that are most adapted to highly toxic soil, which will likely become more prevalent within the city as the climate worsens.

The spaces between these swales and the pedestrian highways/more controlled areas are also uncontrolled - they will be left untouched to form pictorial meadows. Inspired by ‘No Mow May’, these areas will not be altered in any way other than to stop mowing. This will allow the plants stored in the soil here to grow, creating habitat for native insects and generating a distinctly different aesthetic effect as the underlying plant biodiversity is revealed.

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The pictorial meadows will be slashed annually at the end of summer. They’re then raked of cuttings to reduce soil fertility and privilege wildflowers/forbs over the most vigorous weedy species. Contour banks frame the inner-edges of these uncontrolled areas to restrict their growth, catch wind-blown seeds, create a visual boundary and act as a potential fire break for an occasional ‘reset’ burn (every 5-10 years).

The crucial framing of these messy ecosystems will be done simply by regular mowing of the pedestrian highways.

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Swales & Pictorial Meadows | Planting Schedule Though uncontrolled, it is possible to predict the planting schedule for the plant communities that will form in the swales and pictorial meadows of Hybridized Control.

The planting schedule below was generated by identifying plants growing in similar conditions at Northcote Gorge, identifying vigorous/invasive plants growing in the surrounding parklands and residential gardens of our site, and using the Weeds of Melbourne database. The Weeds of Melbourne database identifies a host of exotic species that are considered weeds in Melboure, giving photos of their flowers and a history detailing how they came to be here.

The weeds selected are all tolerant of extreme highs and lows in moisture, can grow in highly polluted and nutrient-high soil and have prolific seeding ability to bring them to site. As can be seen in the photos, there is an exciting aesthetic mix of plant heights, flower colours and leaf shapes/textures that will become visible in these uncontrolled zones.

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Pe cl

Tr fl

So ni

Ma sy

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Al tr

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CODE Pe cl Tr fl So ni Ma sy Fo vu Al tr Vi ma Er bo Ox co Fu ca Br ra Ra mu Di fo Fu mu As su Ro mi Ro ro Tr ca My sy Vi hi Pa ta Hy te Ru pl Eu ch

BOTANICAL NAME Grasses/tussocks Pennisetum clandestinum Forbs Tradescantia fluminensis Solanum nigrum Malva sylvestris Foeniculum vulgare Allium triquetrum Vinca major Erigeron bonariensis Oxalis corniculata Fumaria capreolata Brassica rapa Ranunculus muricatus Dipsacus follonum Fumaria muralis Asplenium subglandulosum Romulea minutifloria Romulea rosea Trifolium campestre Myosotis sylvatica Vicia hirsuta Passiflora tarminiana Hypericum tetrapterum Shrubs Rubus plicatus Euphorbia characias

COMMON NAME

NOTES

HEIGHT

Kikuyu Grass

Incredibly aggressive grass - not desired but probably unstoppable

20cm

Small-leaf Spiderwort Black Nightshade Mallow Fennel Three-Cornered Garlic Greater Periwinkle Flax-leaf Fleabane Creeping Wood-Sorrel White Fumitory Field Mustard Sharp Buttercup Teasel Wall Fumitory Blanket Fern Small-Flowered Onion Weed Onion Grass Hop Clover Wood Forget-me-not Tiny Vetch Banana Passionfruit Square-stalked St John's Wort

Present at Northcote Gorge Present at Northcote Gorge - can be toxic Present at Northcote Gorge - can make tea Present at Northcote Gorge + culinary use Rampant at Northcote Gorge/aroudn this area (already on site) Present at Northcote Gorge Resistant to glycophate Present at Northcote Gorge and Westfield Reserve Spring small white flowers, used medicinally Grows in high moisture & high nutrients. Can be used to produce oil Loves moisture/mud, yellow flowers in summer Impressive, tall flowers - likes mud but can tolerate the dry Small pink flowers Indigenous fern species that likes moisture and tolerates highly toxic soil Common to managed parks in Melbourne (probably here already) Very widespread - small magenta flowers in spring Blob-like yellow bulbous flowers Common to damp inner-city contexts. Cute blue flowers Common to infrastructural edges - will tolerate swale toxicity Beautiful purple flowers - considered for ornamental selection Moisture-loving wort - has herbal remedy properties

Ground 60cm 60cm 2m 30cm 20cm 20cm 20cm 20cm 60cm 20cm <2.5m 60cm 10cm 20cm 20cm 40cm 60cm 30cm 40cm 40cm

Blackberry Mediterranean Spurge

Present at Northcote Gorge, likely to spread to the high moisture swale Hardy Euphorbia species - self-seeds - present in surrounding suburbs

1.5m 1.5m

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Detailed Plan (0.25m Contours) | Protecting the WBPG The central highly controlled Western Basalt Plains Grassland has an important relationship with the two semi-controlled areas to the north and south of it. Hybridized Control seeks to both retain the WBPG in its pure form (as found in the Victorian Volcanic Plain) and allow it to develop into a novel plant community that may be better protected against climate change.

To achieve this, the two semi-controlled areas are set up to capitalise on northerly windblown seed dispersal during summer, when seed production is peaking for most plant communities. This means that the semi-controlled area north of the WBPG must stop seeds blowing south into the WBPG, while the semi-controlled area to the south will catch the seeds drifting out of the WBPG. The northern semi-controlled area will be set up as a weed-suppressing forest. Existing and newly planted allelopathic trees, combined with groundcovers and needle dropping She-Oaks will suffocate weeds here. With further protection from the contour bank, seeds will almost entirely be blocked from entering the WBPG on northerly summer winds.

To the south, a South African Veld (open grassland) plant community is set up to catch the seeds blown out of the WBPG in summer. This veld is similar functionally and aesthetically to the WBPG, but the species are adapted to harsher conditions; better preparing them for climate change. This harshness will be simulated with an imported topsoil mix. The WBPG species’ seeds will enter here on the wind and germinate to form a novel plant community, combining species from both areas. Some species from the WBPG, such as Themada tiandra or Ptilotus, may even genetically hybridize to the harsher soil conditions.

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Semi-Controlled | South African Veld The role of this plant community is to provide testing grounds for improving the climate-durability of the Western Basalt Plains Grassland. It will do this by allowing space for the creation of a novel plant community that combines some WBPG species with hardier plants from a different plant community. This serves to increase biodiversity and hardiness while retaining the aesthetic and functional role of the grassland.

As James Hitchmough states: “Climate change provides new opportunities, and in some cases, an obligate need to use non-native plant species in conjunction with native plant species, not only to reduce the side effects of climate change but also to increase the species diversity and aesthetic value in meadow-like naturalistic planting design.” Hitchmough details in several interviews how South African plants are some of the hardiest and best adapted to the predicted future global climate.

On top of this, mapping of climate analogues for the Australian mainland shows that the area directly north of Melbourne is equivalent to a South African climate. It is reasonable to predict that this climate will spread south to encompass Melbourne as a result of global warming. As such, I decided to use this area to create a South African Veld (grassland).

The South African Veld plant community aesthetically and functionally resembles the Western Basalt Plains Grassland. Its relatively large inter-tussock spaces allow for the potential arrival of seeds from the WBPG. As such, a novel plant community may form here that combines the hardy South African plants with species from the grasslands. This increases biodiversity while maintaining the WBPG species for insect habitat, animal food source and aesthetic importance. This novel plant community will be hardy, cheap to maintain, aesthetically diverse and ready for the future of our climate.

Climate analogues of the Australian mainland show a South African climate immediately north of Melbourne. This will likely spread south as global temperatures rise.

Some plant species that arrive here from the WBPG may even hybridize genetically when interacting with the South African species and their soil conditions. For example, Themada tiandra is highly adaptable and grows in South Africa, while Ptilotus has malleable DNA and grows in extreme heat in WA and QLD. These two species may thrive in the South African Veld context.

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Seeds (such as that of the Themada tiandra) exit the Western Basalt Plains Grassland on northerly summer winds.

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The wind-blown seeds drop into the large inter-tussock spaces of the South African Veld plant community, germinate and form a novel plant community with the South African species..

South African Veld | Planting Schedule The planting schedule for the South African Veld was devevloped based on the plants’ hardines, and their aesthetic and functional similarities to WBPG plants. The plants must be able to grow in tough soil conditions and survive fire. F is necessary for the health of the WBPG species and because it is a key maintenance technique that Hybridized Control is promoting for the future of parks management. Burning will also help eliminate species that might otherwise become overly dominant and to retain the inter-tussock space required.

Some key species are the Portulacaria afra, which can absorb CO2 at ten times the rate of trees in temperate forests. Melbourne-based ‘weeds’ native to South Africa with flowers/ aesthetic meadow-like benefit (Dimorphotheca fruticose, Morea flaccida) are also likely to be very prominent. Most of the species selected have deep, woody root ystems or are summer-deciduous. This means they can survive late-summer controlled burning.

Er cu

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BOTANICAL NAME Grasses/tussocks Er cu Eragrostis curvula Me ne Melinis nerviglumis Ar ju Aristida junciformis Ch sa Chlorophytum saundersiae Mo ce Monocymbium ceresiiforme Forbs Di fr Dimorphotheca fruticosa Mo fl Moraea flaccida Kn uv Kniphofia uvaria Be pu Berkheya purpurea Bu ab Bulbine abyssinica Se ba Senecio barbertonicus Ru ha Ruschia hamata Be ob Becium obovatum Ma ze Macledium zeyheri Di mo Dianthus mooiensis Shrubs Po af Portulicaria afra Le sa Leucadendron salignum

COMMON NAME

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HEIGHT

African Lovegrass Red-top Grass Gongoni Grass Weeping Anthericum Boat Grass

Already naturalised in parts of Australia, it offers similar habitat to Wallaby Grass but hardier Attractive inflorescences, widespread in dry, rocky soils Large tussocks, grows well in wet soil (at the base of the ha-ha wall) Attractive small white flowers (Oct - March). Least concern status = hardy Ranges from riparian to drought-tolerant growing conditions. Attractive copper tussocks

120cm 120cm 2m 1.5m 50cm

Trailing African Daisy One-Leaf Cape Tulip Torch Lily Purple Berkheya Bushy Bulbine Succulent Bush Scenecio Trailing Iceplant Cat's Whiskers Toy Sugar Bush Frilly Carnation

Hardy small flowering herbaceous - weedy in Melbourne - survives Mediterannean climates Attractive orange flowers, grows easily in harsh soils. AIDED BY FIRE in Themada t. grassland Impressive tall red flowers to add visual structure. Hardy against frost & sun Attractive purple-white flowering perennial. Succesful in meadow-style S.A. plantings in the UK Perennial herbb, small yellow flowers. Thrives in rocky grassland soil (ideal) Hardy succulent - can be toxic to animals. Reconsider?

Enjoys very well-drained soil. Thrives in harsh sun and rocky soils. Attractive pink flowers Deciduous, deep root stock prepares it for FIRE. Tolerates drought. Attractive flowers Unique flowers. Can survive fire as it is deeply woody-rooted Small white flowers. Likes drained soil, grows/climbs on grass tussocks over shallow rock

80cm 40cm 1.5m 80cm 80cm 60cm 40cm 40cm 80cm 20cm

Elephant Bush Red Devil

Very hardy soil-wise, grows easily from cuttings & absorbs CO2 ten times faster than avg trees Appears aesthetically native to Australia. Grows quickly in nutrient-poor soil and harsh heat

<5m 1.5m

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Intentionally polluted and coarse soil from construction sites (e.g. East Link)

South African Veld | Function & Maintenance The South African Veld area is set up by scraping 30cm of the existing topsoil to remove the seedbank. This is replaced with a topsoil designed to simulate the harshness of climate change. The soil will be sourced from construction projects (such as the Eastern Tunnel) to try and ensure there it is coarse, nutrient-poor and potentially polluted. It will be mixed with free-drainging sandy soil where necessary and stones are desirable to encourage thermal mass. This is all designed to emulate drought, rising temperatures and the effects of acid rain - results of climate change.

South African Veld species will then be planted as seedling. They are selected based on their hardiness and their aesthetic and functional similarities to WBPG plant species. Most will be fire-tolerant too. Burning is crucial every 4 years to maintain the health of WBPG species tht enter here and to regulate the weediness of the South African species. We want the novel plant community forming here to be fire-tolerant as this will be a crucial part of the maintenance regime in the future.

By catching the Western Basalt Plains Grassland’s wind-blown seeds a novel plant community will form here that combines the hardy South African plants with species from the grasslands.

This will increase biodiversity, maintain animal habitat and food sources, improve hardiness of the new grassland and reduce maintenance costs. Species such as Themada tiandra and Ptilotus may even genetically mutate here. They are both shown to grow in harsher cliamtes and have adaptive DNA.

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30cm deep topsoil.

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Simulates drought with very little water retention (sandy/stony). The soil also generates increased heat through the stony rubble which creates thermal mass.

The soil toxicity is intentionally high, emulating the effects of climate change-induced acid rain.

This is all aimed to simulate harsh, climate change-inspired growing conditions.

Stony soil

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BBQ Area

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Semi-Controlled | Weed-Suppressing Forest This semi-controlled area is designed to suppress air-borne weeds that may infect the WBPG directly south during summer, when predominant northerly winds are blowing. It will take the form of a weed-supressing forest. It is planted with predominantly River She-Oak (Cassuarina cunninghamiana) and Monterey Pine (Pinus radiata). This species suppress understorey weed growth through a combination of dropped needle-mats from the She-Oaks and through the allelopathic qualities of the pines - as illustrated at Northcote Gorge.

The lower-storey vegetation under these trees consists of plants that have been identified by observation or from research into the WBPG. Hardenbergia and Silver Banksia have both been observed living under heavily matted She-Oak canopies, the Silver Banksia also possesses allelopathic qualities. Lemon Beauty-Heads are brought here from the WBPG because they form a weed-suppressing ground cover, while the Hairy Anchor Plant is here because it prefers these woodland conditions to its original EVC (WBPG).

At Northcote Gorge, in plant community #2, there is a row of allelopathic conifers. The weeds that are extensive throughout the rest of the site barely grow under these trees. The thin, nutrient-poor soil also reduces the growth of exotics, but this chemical alteration to the soil is a crucial element adapted into the design for Hybridized Control. The existing eucalypts and conifers in this part of the site will aid this allelopathic soil control.

The Weed-Suppressing Forest will connect to an uncontrolled swale along Heidelberg Rd, giving great power to visualise the efficacy of these weed-suppressing techniques on the novel ecology here. The southern border will be emphasized with a contour bank to further protect the WBPG – this will drop immediately into the ha-ha and create a deep trench – potentially interesting space for a novel plant community.

To further supress weeds here groundcovers will be implemented to shade out the underlying exotic species. For example, the Australian native Nodding Saltbush (Einadia nutans) will form a thick carpet beneath gum trees that completely suffocates other plants. The She-Oak trees will also drop their needles and after several years of growth a mat/mulch will be formed that further supresses the weeds under their canopy.

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Ei nu

Dropped needles form a mat over several years which suffocates underlying weeds

Allelopathic tree roots chemically alter the soil, killing many weed species.

CODE

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BOTANICAL NAME Trees Ca cu Casuarina cunninghamiana Pi ra Pinus radiata Al ve Allocasuarina verticillata Ba ma Banksia marginata Forbs Ca ci Calocephalus citreus Shrubs Ha vi Hardenbergia violacea Di pu Discaria pubescens Ei nu Einadia nutans

COMMON NAME River She-Oak Monterey Pine Drooping She-Oak Silver banksia

Method of Weed Suppression Needles drop & form mulch Allelopathic Needles drop & form mulch Allelopathic

Lemon Beauty Heads Weed-suppressing ground cover False Sasparilla Hair Anchor Plant Nodding Saltbush

Placement

Soil/Growing Conditions

HEIGHT

Southern bank to receive sun, prevent contour bank slope eroding and mulch seed buildup Sunny positions near non-allelopathic existing trees Southern bank (as with River She-Oak) In line of views on Heidelberg Rd and within park - in sun

Not fussy, prefers sandy loam - tolerates infertility & drought Performs best in well-drained soil Tolerates most soils - needs sun Prefers well-drained sandy but not fussy

30m 30m 7m 10m

Part of the WBPG ecology, planted here too - likes sunny position

Give it sun - likes drier clay soils

60cm

Not fussy Likes moist soil - plant at the foot of the contour bank Dry, rocky soils - well drained

80cm 1m 30cm

NA - grows well in these conditions Under Sheoaks and Eucalypts - based on observation at Footscray Park NA - endangered sp. to protect Taken from the WBPG - planted here as it prefers woodland - place in shadow of Sheoaks Forms a thick ground cover Thrives beneath the eucalypts - will attract native lizards w/ berries

Weed-Suppressing Forest | Planting Plan (0.25m Contours) Observational precedents.

The allelopathic weed-killing effects of a Pinus radiata at Footscray Park.

A Hardenbergia is one of very few shrubs surviving in an established River She-Oak forest.

Drooping She-Oak sit atop a hill that they have almost entirely cleared of Kikuyu Grass.

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Existing allelopathic conifer

Existing allelopathic eucalypt

Casuarina cunninghamiana

Einadia nutans

Pinus radiata

Hardenbergia violacea

Banksia marginata

Calocephalus citreus

Discaria pubescens

Allelopathy zone

10m

50m

20m

100m

200m

40m

N

N

Existing non-allelopathic tree 47

Highly Controlled | Western Basalt Plains Grassland The centrepiece of Hybridized Control is a Western Basalt Plains Grassland (WBPG). The WBPG plant community has been selected as the focal point of the design because it is one of just 15 biodiversity hotspots in Australia, it is critically endangered - less than 5% of original Victorian Volcanic Plan Temperate Grasslands exist now and are highly fragmented. One third of the remnant WBPG however, if found within the Merri Creek Catchment - upstream of our site. This gives it a symbolic and physical attachment to Westfield Reserve.

The WBPG ecology is also worth preserving as it is home to many species that could benefit parks management in Melbourne as our climate worsens. Most of the species within the WBPG are adapted to harsh soil conditions, intense heat, sun and wind exposure, and drought – they’re also not fussy about soil toxicity.

The Western Basalt Plains Grassland will be both protected in its pure form and allowed to spread out by wind-borne seed dispersal to form novel plant communities. The pure form WBPG will be segregated by a bluestone ha-ha wall, which creates a necessary cue to care for this plant community which is emphasised by its centrality. Retaining the purity of this central WBPG is important as it acts as a physical and visual database for the ecology.

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WBPG | Deriving a Form After several iterations, this is the final form decided for the Western Basalt Plains Grassland. It was derived by this process: 1. Placed centrally as the park’s focal point (giving it a cue to care) 2. Extended south to approach the BBQ area - the key existing pedetrian congregation point. This also retains more wind-borne seeds within the grassland in summer during peak seed production, as predominantly northerly winds are blowing.

3. Fully segregated by bluestone ha-ha as a fencing cue to care and to retain the grassland’s purity.

4. Within the border there are four ridges designed to create north-facing hotspots and south-facing colder zones.

5. These are bridged by a slightly raised spine that creates the picturesque sense of foreshortening for the key viewpoints, giving the impression of a larger grassland. The spine foreshortens the view be manipulating the sense of depth. Emerging bluestone pieces act like the architectural reliefs employed by William Kent at Rousham House. These also act as a natural mulch and generate thermal mass (taken from Northcote Gorge).

6. The trees either side act as a physical border – we do not want them within the grasslands as they will absorb too much moisture and incur costs when excavating the topsoil.

7. The minimum size for a WBPG ecology is 500m2 (Department of Sustainability & Environment) - our grassland is around 2,400m2.

N

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50m

100m

200m

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WBPG | Seed Dispersal & Planting Schedule These are the species that will make up the Western Basalt Plains Grassland. All are indigenous to Australia and currently grow in the Victorian Volcanic Plain, although most are threatened if not endangered. As a general description; the ground layer is dominated by native tussock-forming perennial grasses (Kangaroo Grass, Wallaby Grass or Spear Grass) with a variety of herbs, mostly from the daisy (Asteraceae), lily (Anthericaceae, Asphodelaceae, Phormiaceae), pea (Fabaceae) and orchid (Orchidaceae) families occupying the spaces among grass tussocks. 15-25% bare soil between tussocks is ideal.

Three key species dictated the formation of the grassland. Firstly; Themada tiandra (Kangaroo Grass) which is the dominant species of this EVC - many other species are subdominant to it. Kangaroo Grass is crucial in dictating fire movement (used as kindling).

Slashing of the grass to encourage seed growth will also produce a rich humus layer and mulch. Kangaroo Grass is also important as it is hardy and adapted to a wide range of climates, meaning it will be one of the most suited to producing a novel plant community outside of the WBPG.

Th ti

Secondly, the endangered Rutidosis leptorrhynchoides (Button Wrinklewort) is a crucial component. It has strong aesthetic benefit with tall yellow flowers and several other forbs are subdominant to it. Lastly, Ptilotus macrocephalus (Featherheads) was influential.

The Featherheads provide a uniqe structural aspect to the grassland (known coloquially as the ‘trees’ of the WBPG). They require extremely porous soil, which invites variety to the soil structure. They are easily wind-dispersed and genetically malleable - meaning they will play an interesting role in the formation of a novel plant community.

The WBPG will be planted with by seed, using three differernt dispersal techniques. Firstly a mulch mix will cover the grassland. This mulch mix will have seeds stored within it that are too hard to clean and purify. The mulch mix also helps to quickly generate a humus layer. Secondly, the majority of species will be sprinkled in a general seed mix underneath the mulch (mulching at only 20mm thick). Hitchmough’s design considerations have dictated which species are given a higher or lower concentration. These considerations are; plant height variation, flowering season, biodiversity, quantity, and usefulness (human food source, attracting native insects). Lastly, some species will be hand-sown to ensure adequate spacing and reach deeper into the topsoil (around 10cm).

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Themada tiandra | Kangaroo Grass (majority) Rytidosperma caespitosum | Wallaby Grass Austrostipa stipoides | Prickly Spear-Grass Ptilotus macrocephalus | Featherheads Calocephalus citreus | Lemon Beauty-Heads (sparingly)

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Hand Sowing (Under Mulch)

Rutidosis leptorrhynchoides | Button Wrinklewort Leucochrysum albicans | Hoary Sunray (30cm gaps, Diuris fragrantissima | Sunshine Diuris 10cm depth) Discaria pubescens | Hairy Anchor Plant Pimelea spinescens | Spiny Rice-Flower (2m gaps, Cullen parva | Small Psoralea 10cm depth) Pterostylis truncata | Brittle Greenhood (higher %) Scenecio macrocarpus | Large-Fruit Groundsel Calocephalus lacteus | Milky Beauty-Heads Diuris basaltica | Golden Moth Orchid Chrysocephalum apiculatum | Common Everlasting (sparingly) Microseris lancelota | Murnong Podolepis jaceoides | Showy Podolepis Convolvulus erubescens | Pink Bindweed Leptorhynchos squamatus | Scaly Buttons Bulbine bulbosa | Bulbine Lily (higher %) Acaena echinata | Sheep’s Burr (higher %) Geranium retrorsum | Common Crane’s Bill Arthropodium strictum | Chocolate Lily (higher %)

50m

100m

Pt ma

Po ja

Ca ci

Th ti Ry ca Au st

General Seed Mix (Under Mulch)

25m

Sc ma

CODE

Mulch Mix | Cover WBPG (20mm depth)

Ry ca

Ru le Di fr Di pu Cu pa Pt tr Sc ma Pt ma Ca la Le tr Pi sp Di ba Ch ap Mi la Po ja Ca ci Co er Le sq Bu bu Ac ec Ge re Ar st

BOTANICAL NAME Grasses/tussocks Themada tiandra (T. australis) Rytidosperma caespitosum Austrostipa stipoides Forbs Rutidosis leptorrhynchoides Diuris fragrantissima Discaria pubescens Cullen parva Pterostylis truncata Scenecio macrocarpus Ptilotus macrocephalus Calocephalus lacteus Leucochrysum albicans Pimelea spinescens Diuris basaltica Chrysocephalum apiculatum Microseris lanceolata Podolepis jaceoides Calocephalus citreus Convolvulus erubescens Leptorhynchos squamatus Bulbine bulbosa Acaena echinata Geranium retrorsum Arthropodium strictum

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COMMON NAME

Kangaroo Grass Yes Common Wallaby GrassYes Prickly Spear-Grass Yes Button Wrinklewort Sunshine Diuris Hairy Anchor Plant Small Psoralea Brittle Greenhood Large-Fruit Groundsel Featherheads Milky Beauty-heads Hoary Sunray Spiny Rice-flower Golden Moth Orchid Common Everlasting Murnong Showy Podolepis Lemon Beauty-Heads Pink Bindweed Scaly Buttons Bulbine Lily Sheep's Burr Common Crane's Bill Chocolate Lily

Yes Yes ?

Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

00m

Au st

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Di pu

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Ca la

Le tr

Pi sp

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Co er

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Bu bu

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Ge re

Ar st

N

2-3 YR FIRE?

SEED SOWING

SOIL

DESIGN IMPACT

FLOWERS

HEIGHT

s + slash annually Autumn (mulch) s +slash annually Autumn (mulch) s +slash annually Autumn (mulch)

Not fussy Shallow, stony soil Sandy soils, well-draining

Mulch seed-sowing process + plant in a manner that controls fire movement and breaks frost Place close to porous zones as it prefers stony soils, seeds must be in very shallow soil (mulch mix) Likes coastal zones - plant into a different area? Can be planted in frost breaks & to stop erosion

Early Summer Early summer

1.5m 90cm 80cm

s s

Fertile, red-brown clay soils, well-draining, stony Heavy clay-loam soil, stony Heavy clay-loam soil, stony More fertile, rocky clay-loam soils Most soil types, slightly higher moistuire retention Red-brown clay/earth soil Sandy, very porous, high draining (25% - 30% AFP) Versatile - loamy or sandy soils + rocks Heavy clay-loam soils - dry + full sun Well-drained soils on basalt Heavy basaltic soils Red-brown clay/earth soil Not fussy Heavy clay to sandy soils (wide range) Heavy clay-loam soil, stony Light, sandy-loam soils Clay - moist, well-draining Fertile, red-brown clay soils, well-draining, stony Fertile, red-brown clay soils, well-draining, stony Sandy, drier soils Sandy, draining soils

Needs high soil fertility - create mounds to allow the soil change and space for forming a dense cluster Needs inter-tussock space to grow - place near the R.leptorrhychoides mounds to avoid dominant grass Plant in a different area? Prefers grassy woodland. Needs moisture/riverbanks.

Plant in water-catching depressions near the Button Wrinklewort (more fertile soil) w/ south-facing aspect Place in the south-facing aspect for less harsh sunlight Subdominant to Button Wrinklewort - plant together Needs highly porous soil Highly adaptive to soil and climate conditions, spread in general seed mix - slightly prefers higher moisture Adapted to urban areas, needs open ground. Place near WPBG edge because it flowers in WINTER!!

Associated w/ Kangaroo Grass. Winter flowers and likes sparse planting - very lobng-lived Associated w/ Kangaroo Grass - needs intertussock space. Plant on south-facing aspect Plant in north-facing aspect. Needs very little maintenance, try to keep sparse. Likes full sun (inter-tussock) Very hardy, not fussy no aspect or soil - place near the edge for user access as its tubers can be eaten Hardy, food source for native bees Supresses weed growth as it forms a ground cover - mix seeedheads into mulch sparingly Likely to grow in slightly shaded area of high porosity (near the Featherheads) Moister soil, conditions - southern aspect hardy/well-adapted and provides food source = use heavily in seed mix. Grows in moister conditions Winter flowering Prefers moister/shadier southern aspect Very versatile, prefers drained sandy soil. Heavy use in seed mix for aeesthetics + as a food source

Oct - Jan Oct - Nov Nov - Jan Oct - Feb Autumn Sep - Nov Oct - Feb Dec - March Aug - Dec Aug - Dec Sep - Oct Sep - March Sep - March Aug - Nov Oct - March Sep -April (1 day) Sep - Dec Sep - March Aug - Nov Jul - Jan Sep - Dec

80cm 20cm 1m Ground 15cm 70cm 80cm 30cm 20cm 60cm 15cm 30cm 20cm 50cm 50cm Creeper 50cm 50cm 40cm 1m 80cm

Early autumn (mix) Early autumn (mix) ? s (below ground) Early autumn (mix) s (below ground) Autumn (mix - higher) s Early autumn (mix) s Late spring (mulch?) s Autumn (mix) s Autumn (hand, 30cm gaps) s Autumn (hand, sparse) s Autumn (mix) s Autumn (mix - sparingly) s (below ground) Autumn (mix) s Autumn (mix) s Autumn (mulch, sparingly) s Autumn (mix) s Early autumn (mix) s Autumn (mix) s Autumn (mix - higher) s Autumn (mix) s Autumn (mix - higher)

STATUS Least concern Not at risk Not at risk Endangered At risk Threatened Endangered Not at risk Not at risk Not at risk Endangered Cr. Endagered Endangered Not at risk Not at risk Not at risk Not at risk Threatened Not at risk Not at risk Not at risk Not at risk Not at risk

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WBPG | Soil Structure Soil variation in density, moisture and pH is key in creating a grassland rich in vegetation variety. Perennials to set their roots in the less dense loams between bluestone pieces/clay. The plan below shows the soil types that will make up the WBPG to encourage a rich grassland with a visible abundance of plant-life. The form and locations of the soil types has been decided based on research into the individual plant needs. Generally, the clay-based soils are north-facing and the porous, sandy soil is south-facing. There is a range of fertility.

Bluestone - shallow stony soil Rytidosperma caespitosum | Wallaby Grass Ptilotus macrocephalus | Featherheads

Sandy soil - high porosity (AFP 30-40%) Austrostipa stipoides | Prickly Spear-Grass Pimelea spinescens | Spiny Rice-Flower Convolvulus erubescens | Pink Bindweed Geranium retrorsum | Common Crane’s Bill Arthropodium strictum | Chocolate Lily

Heavy red-brown clay loam Diuris fragrantissima | Sunshine Diuris Discaria pubescens | Hairy Anchor Plant Pterostylis truncata | Brittle Greenhood Scenecio macrocarpus | Large-Fruit Groundsel Leucochrysum albicans | Hoary Sunray Diuris basaltica | Golden Moth Orchid Chrysocephalum apiculatum | Common Everlasting Calocephalus citreus | Lemon Beauty-Heads Leptorhynchos squamatus | Scaly Buttons Bulbine bulbosa | Bulbine Lily Acaena echinata | Sheep’s Burr

High fertility clay Rutidosis leptorrhynchoides | Button Wrinklewort Cullen parva | Small Psoralea

Any/all soil conditions Themada tiandra | Kangaroo Grass Calocephalus lacteus | Milky Beauty-Heads Microseris lancelota | Murnong Podolepis jaceoides | Showy Podolepis

Bluestone - shallow stony soil

Sandy soil - high porosity (AFP 30-40%)

Heavy red-brown clay loam

High fertility clay

N 52

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50m

100m

200m

WBPG | Sectional Perspective A sectional perspective highlighting the soil types and the physical structure of the WBPG.

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Western Basalt Plains Grassland | Perspectives Here are two perspectives of the focal Western Basalt Plains Grassland in different seasons of different years. The left-hand image shows a person viewing the Grassland in spring, around 7 years after it is initially set up. As can be seen, at his feet the WBPG species have spread into the surrounding areas and formed novel plant communities.

The right-hand image shows the initial controlled burn of the grassland. The burns take place every 4 years to kill weeds, help seeds germinate, clear dead wood and maintain inter-tussock space.

Hybridized Control hopes to have illustrated how variation in landscape control can improve the aesthetic and functional requirements of inner-city parks. Burning in particular is a crucial element of the new hybrid land management practice. We hope this toolkit may serve useful in future-proofing urban green areas against the effects of climate change, as council parks budgets are ever-decreasing.

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Video Link & Acknowledgements The final five-minute video presentation of Hybridized Control is publicly accessible here: https://rmit-arc.instructuremedia.com/embed/4d50036e-550b-4b54-b13b-ee5caee7863f Thank you to Alistair, my classmates, Maia, Jimmy, Will, Isaac and all readers.

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