Just a stone's throw from Curtin is a bushland more biodiverse than Kings Park. Find out how a team of volunteers are not only conserving that bushland, but leading a daring restoration project.
Just a stone's throw from Curtin is a bushland more biodiverse than Kings Park. Find out how a team of volunteers are not only conserving that bushland, but leading a daring restoration project.
In this episode, our hosts David and Celeste are joined by plant biologist and Curtin Research Fellow, Dr Michael Just. They talk about how the Friends of Jirdarup Bushland are leading the transformation of a former rubbish dump into a pristine banksia woodland.
Michael also delves into seed sourcing and the challenges of getting anything to grow in a sandpit.
Note: the introduction incorrectly stated the sandpit is on track to become the world's first fully-restored banksia woodland; it is set to be one of a few successfully restored woodland areas.
Episode feature image: Red-capped robin by Georgina Wilson.
Michael is a plant biologist with expertise in seed dormancy, germination physiology, and restoration ecology. He holds a Doctor of Philosophy from Curtin University, where he conducted research on intractable seed dormancy and its impact on biodiversity in Southwest Australia.
This podcast is brought to you by Curtin University. Curtin is a global university known for its commitment to making positive change happen through high-impact research, strong industry partnerships and practical teaching.
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Read the transcript: https://thefutureof.simplecast.com/episodes/urban-bushland/transcript
Host: David Karsten and Celeste Fourie
Producer: Emilia Jolakoska
Researcher: Zoe Taylor
Executive Producer: Natasha Weeks
Curtin University acknowledges Aboriginal and Torres Strait Islander people, the First Peoples of this place we call Australia, and the First Nations peoples connected with our global campuses. We are committed to working in partnership with Custodians and Owners to strengthen and embed First Nations’ voices and perspectives in our decision-making, now and into the future.
Curtin University supports academic freedom of speech. The views expressed in The Future Of podcast may not reflect those of Curtin University.
This podcast is brought to you by Curtin University. Curtin is a global university known for its commitment to making positive change happen through high-impact research, strong industry partnerships and practical teaching.
00:00:00:00 - 00:00:10:08
Celeste Fourie
This is The Future Of, where experts share their vision of the future and how their work is helping shape it for the better.
00:00:10:10 - 00:00:11:14
David Karsten
I'm David Karsten.
00:00:11:16 - 00:00:40:18
Celeste Fourie
And I'm Celeste Fourie. In Perth, WA, just a 15 minute walk from Curtin's Bentley campus, there's a sand pit, but this isn't just any sand pit. After 20 years, this former rubbish dump is on track to become [one of] the world's first fully restored Banksia woodland. Once complete, the woodland will be a haven for plants, animals and humans alike, and a blueprint for the best practice in land restoration.
00:00:40:20 - 00:00:54:11
Celeste Fourie
This ambitious project is the work of a team of dedicated volunteers called the Friends of Jirdarup Bushland, in partnership with the Town of Victoria Park, local First Nation elders and Curtin researchers.
00:00:54:13 - 00:01:10:19
David Karsten
With us today is one of those researchers plant biologist, doctor Michael Just. And Michael is here to tell us all about the restoration and just what can be achieved when a community rallies behind a cause. If you'd like to find out more about this research, visit the links provided in the show notes.
00:01:10:21 - 00:01:22:17
Celeste Fourie
Urban bushland is vital to ecosystems, but it's also important to human health. Can you tell us a little bit more about the benefits of remnant bush areas?
00:01:22:19 - 00:01:51:01
Michael Just
Yeah, of course I can. So urban bushland I guess can really have two functions. So ecologically they provide habitat pollination networks. They're important for seed sourcing, which I'm sure will touch on, as well as refuges for native species and heavily modified landscapes. And then the other side is socially. So they make cities healthier and more livable by cooling neighborhoods, providing amenity, giving people daily access to nature.
00:01:51:03 - 00:01:57:23
Michael Just
So we often think of bush lands as a luxury, but in practice they function as kind of essential urban infrastructures.
00:01:58:00 - 00:02:06:13
David Karsten
And, Michael, where are we at? Are we doing a good job of of retaining, I guess, urban ecosystems and urban bushland?
00:02:06:15 - 00:02:25:20
Michael Just
I'm probably biased, but my answer is going to be no. When we look at the Kensington Bushland Precinct, it's really the only one this side of Kings Park. And they're increasingly rare in urban landscapes. So my answer is going to be no. There are definitely examples, like the one we're talking about today where good things are happening.
00:02:25:22 - 00:02:28:09
Michael Just
But by and large, yeah.
00:02:28:11 - 00:02:40:18
David Karsten
Let's let's just delve a little deeper into, the role it plays, particularly for native wildlife and what happens when those corridors are either reduced or well cut out altogether. What that means.
00:02:40:20 - 00:03:06:00
Michael Just
Yes. So I mean there's there's lots of things. Habitat fragmentation is really big. So greater distances between patches mean species don't get the kind of genetic diversity they need. We have issues where, you know, with fewer and fewer patches, our ability to source material to restore these things to, to put them other places are fewer and far between.
00:03:06:02 - 00:03:26:08
Michael Just
The Town of Victoria Park is a good example. They have this, you know, eight, nine hectare bushland. They want to do a four hectare rehabilitation. Where do they get the seed from that? Do they strip the vegetation they have to provide for the new spaces? So there's lots of issues that that kind of compound and build up as these things get fewer and far between.
00:03:26:10 - 00:03:47:23
David Karsten
Michael, your particular area of interest locally is the Jirdarup Bushland. It's a it's a former sandpit. That that you're it's that the friends of that bush land are returning to former glory as a as a banksia woodland. With the end goal of replicating the bushland growing next to the sandpit that you've mentioned, the Kensington bushland.
00:03:48:00 - 00:03:54:22
David Karsten
What makes this area special? Other than the fact that it is one of the few this side of Kings Park?
00:03:54:24 - 00:04:19:20
Michael Just
So I guess it's the kind of intersection of a few things. The, the willingness of the town, the Town of Victoria Park, the ongoing kind of engagement and pressure from the community group. The interaction or the, the, the, the town itself has sought out, expertise from local Indigenous elders as well as us here at Curtin University.
00:04:19:20 - 00:04:31:13
Michael Just
So there's a lot of people that have come to the table to make this happen. And I think that's what really makes it stand out compared to other projects that that exist around Perth.
00:04:31:15 - 00:04:36:13
Celeste Fourie
We keep referring it to as a sandpit. Why is it a sandpit?
00:04:36:15 - 00:05:00:12
Michael Just
So it was originally a rubbish dump. Well, it was originally Banksia woodland. Okay. And that was cleared to facilitate a rubbish dump. And that's something that's happened across the greater Perth region for decades and decades and decades. You mine out a big hole, you sell all the sand, make a bunch of money off that, and then you backfill it with municipal waste and then cap it.
00:05:00:14 - 00:05:21:02
Michael Just
And that's basically what happened at, Jirdarup Bushland or at the sandpit. And then for the last two decades or so, it was a like a lay down facility for the town. So for, urban vehicles and whatnot. And then I believe it bounced around, a bit with approvals. So, you know, could it be a park?
00:05:21:04 - 00:05:36:01
Michael Just
No, because it's got uncontrolled, uncontrolled fines and asbestos and stuff below 1.5m. And so there's a lot of work that's gone into making sure it's safe, zoning it and finding what uses it. Could be it could be good for very interesting.
00:05:36:03 - 00:05:51:04
David Karsten
It just sounds like a massive project. You're you're creating something from almost nothing. It's. Yeah, I imagine that, I guess from a soil profile perspective, there was so much work to do. Was there a soil profile?
00:05:51:06 - 00:06:08:03
Michael Just
So I guess this is a good point, a good time to point out the role that the Town of Victoria Park has had here. So I've come in in the last kind of three years to provide expertise and to provide, technical support. But the town has been kind of scoping this out for a long time.
00:06:08:03 - 00:06:32:17
Michael Just
So they've had, Department of Water out there. They've had, you know, endless contractors out there. Understanding the soil profile, understanding what issues exist there, and then kind of coming up with strategies to, to get around them. So basically, we are limited. We cannot excavate more than a metre and a half. Because then you start getting to those uncontrolled fines and who knows what we're going to find down there.
00:06:32:18 - 00:06:35:07
Michael Just
So yeah, so that is a constraint on the project as well.
00:06:35:09 - 00:06:42:19
David Karsten
It's through the lens of your specialty. Michael, what did you I guess what did you see as the main challenges for for establishing new plantings there?
00:06:42:21 - 00:07:07:04
Michael Just
So for me and I guess the area that I work in, it's always, getting the diversity. So 35% of our flora locally, we can't grow reliably. And that's, you know, not even to say like what is available if things are difficult or complex, they're typically not available on the market. And they typically don't get used in, in projects like this.
00:07:07:04 - 00:07:21:18
Michael Just
And again, this is where the town of Victoria Park has been really good. They've had a strategy going for at least a few years now, 5 or 6 years, where they've been trying to source material and get a really diverse group of plants to put back there.
00:07:21:21 - 00:07:43:07
David Karsten
You mentioned local Michael. It really is. Yeah. If you could paint a picture for us, localised flora really does mean local to this area. It's almost down to a few postcodes. It's not you're not going to necessarily grow something from the hills in Victoria Park, would you? If you are wanting to stick to a to a local palette.
00:07:43:09 - 00:08:06:00
Michael Just
Yeah. So there's there's a lot of debate around that. And the concept is provenance. And how far can we go from a site to source material for that site? The arbitrary numbers that are typically put on restoration projects is 50km from the site. But that really is kind of just plucked out of the air. There's not a whole lot of science that's been done to date.
00:08:06:02 - 00:08:22:15
Michael Just
Although it is coming to kind of tell us, you know, what is appropriate sourcing. And as you know, these landscapes get more and more fragmented as these bushlands get harder and harder to find. The distances that might be acceptable to source material from may have to grow to to facilitate it.
00:08:22:17 - 00:08:30:13
Celeste Fourie
Can you tell us a little bit about how you can actually get plants to grow on a former landfill site?
00:08:30:15 - 00:08:33:04
David Karsten
Yeah. What do you have to do? Like, yeah.
00:08:33:06 - 00:08:35:04
Michael Just
Stick them in. Stick them in. And hope.
00:08:35:05 - 00:08:36:09
Celeste Fourie
Seems difficult.
00:08:36:09 - 00:08:51:19
David Karsten
That sounds that sounds like me gardening. It just, you know, stick it in and hope for the best. Are you serious? I mean, are there any soil amendments that you had to make, or is it a case of these are the conditions? Well, yeah, these are the conditions. And if the plants cannot survive it, then they're not suitable.
00:08:51:21 - 00:09:14:00
Michael Just
That's essentially the the avenue we're taking here. Okay. Because of the nature of the site and, you know, the inability to go in there and dig it all up. And then with the cost of bringing in clean fill sand or other material, the strategy that I've advocated for is, well, let's try on smaller scales and see and then adapt and move.
00:09:14:02 - 00:09:33:08
Michael Just
Beyond that, we when we teach restoration here at Curtin, we often say it's not so much about the snapshot or the endpoint, it's about the trajectory, and it's about getting things kind of in motion. And with the community engagement on this one, that community engagement should long outlive kind of short term government funding cycles and stuff like that.
00:09:33:08 - 00:09:51:14
Michael Just
So this is a project that should go for decades, and therefore we're not really constrained to getting it right in the next five years. So for the last 6 to 12 months, we've seen the process, the project shift from concept to implementation. Which means plant orders are being put in. We, recently well, last planting season.
00:09:51:14 - 00:10:10:21
Michael Just
So last kind of May-June, we put in a small planting trial. We put maybe a thousand plants in there and tested, two different planting methodologies. So really deep stem planting. This is kind of just as normal. And then the presence of, of a thick layer of mulch versus no mulch.
00:10:10:23 - 00:10:12:12
David Karsten
And any supplementary watering or.
00:10:12:12 - 00:10:31:15
Michael Just
No. So we advocate against watering. If you plant at the right time of year and you take advantage of the rainfall, then in theory, you shouldn't have to water. And the more water you provide, things are going to keep their roots at the surface, chasing that water rather than if you don't water them, they're going to drive their roots further down, chasing water at depth.
00:10:31:17 - 00:10:35:11
Michael Just
And that's going to give you more survival long term.
00:10:35:13 - 00:10:39:18
David Karsten
So which which planting has proven the most successful? Too early to tell.
00:10:39:20 - 00:10:40:17
Michael Just
It's not too early to tell.
00:10:40:17 - 00:10:43:05
Celeste Fourie
So we was this last year, May-June? Yeah.
00:10:43:05 - 00:11:02:12
Michael Just
Okay. Yeah. Last year, major, and we put a subsample of plants in, we, take advantage of the environmental research projects here at Curtin, which is a third year unit. So we get students out there to to monitor these things and do things. So they did the original monitoring. And then we, doing it again, in the second half of this year.
00:11:02:14 - 00:11:18:20
Michael Just
But we've been out there having a look and basically the addition of mulch and deep stem planting is the best, but that's not going to give us this banksia woodland outcome. The mulch isn't conducive to ongoing recruitment. And it has, you know, other impacts esthetically.
00:11:18:20 - 00:11:20:16
David Karsten
And what do you mean by ongoing recruitment.
00:11:20:20 - 00:11:46:12
Michael Just
So plants dropping seeds onto the ground into mulch. Probably not going to recruit. And so the absence of mulch has always been my what I advocate for, deep stem planting versus deep stem stem planting with mulch. There's maybe a 10-15% difference in survival, which for the cost of mulch and probably cost, you know, upwards of half $1 million to to mulch the whole site.
00:11:46:14 - 00:11:51:20
Michael Just
So you better off putting that money into weed control, additional plantings, follow up plantings.
00:11:51:22 - 00:11:56:15
David Karsten
And then you also have the advantage of of more effective recruitment. So what you saying right. Yeah.
00:11:56:20 - 00:11:58:01
Michael Just
In an ideal world, yeah.
00:11:58:03 - 00:12:10:22
David Karsten
So where are you where are you at now? Is it a case of another winter of testing the mulch versus no mulch theory, or are you going ahead and doing a widespread planting date with no mulch?
00:12:10:24 - 00:12:14:07
Michael Just
Yep. So we're going ahead.
00:12:14:10 - 00:12:15:21
David Karsten
Need to know these things.
00:12:15:23 - 00:12:34:24
Michael Just
So, yeah, this season. So may June, we should start to see the first real full scale plantings happen at the site. Depending on plant supply will depend exactly how big of an area is planted. But we're looking at, you know, somewhere around a hectare, maybe a little less this year.
00:12:35:01 - 00:12:40:12
David Karsten
That's a lot of that's a lot of, a lot of plantings. You just one man, Michael.
00:12:40:14 - 00:13:00:21
Michael Just
So this is again, where the town is, is really instrumental to all of this, and I need to keep emphasising that this is led by the town and the friends group. I'm just the, you know, the doddery academic that's kind of dropped in. But they. Yeah. So they have engaged a local contractor, who is an expert in this space as well.
00:13:00:21 - 00:13:10:10
Michael Just
And, and a lot of the trials that we do are just informing the community and the stakeholders of stuff that a lot of these consultants already know.
00:13:10:12 - 00:13:24:18
David Karsten
From your perspective, how important is is community by-in on on a project like this? I mean, it's quite this sort of thing is actually quite successful in, in other parts of Perth. It is community by and essential to to see this through.
00:13:24:20 - 00:13:49:15
Michael Just
I believe so, when we're talking about things that require money and are not, you know, directly evident in the benefit they provide to the community. You can get a lot of pushback. And so having the community on board to, to drive these things through the, the political cycle and beyond, those short term political cycles to see these projects continue, you know, for decades, the community is instrumental.
00:13:49:17 - 00:14:02:02
Michael Just
And even in just deciding, you know, who am I to say, as a researcher, that this sandpit should be a banksia woodland? If the community says it should be a car park, or then should it be a car park? So community is the kind of core of these things.
00:14:02:02 - 00:14:13:14
David Karsten
I think there are around a million hectares of degraded land around W.A. Michael. Are there other projects that are similar to the sandpit restoration that that you know about and that you kind of excited about?
00:14:13:16 - 00:14:35:17
Michael Just
Yeah, definitely. So the project, I there's a project I lead here at Curtin, which is funded by the Public Transport Authority. So the Byford to Armadale rail extension, the arm of Metronet, had an impact on a critically endangered woodland community here in Perth. So it's one of the rarest vegetation communities on the planet, has less than 100 hectares of it to date.
00:14:35:19 - 00:15:04:14
Michael Just
And because of that, the environmental offsets that had to be achieved for the rail extension, you know, weren't able to be achieved because typically these projects will go and buy up vegetation communities to offset the impact of, of, you know, what they're doing. And in this case, it just didn't exist to buy up. So we, three years into a five year project, with the Public Transport Authority, understanding this vegetation community and focusing very heavily on, sourcing plant materials.
00:15:04:14 - 00:15:22:06
Michael Just
So there's over 360 species of plant that exist out in this little 35 hectare reserve out in Byford. And we're getting those into production systems here at Curtin to be able to supply the, the broader industry with, with, you know, correct provenance material, to do these restoration projects.
00:15:22:08 - 00:15:26:22
David Karsten
Is that, anything to, do with Thilo Kruger in the sun dews? Yeah. He's a good guy.
00:15:26:22 - 00:15:42:05
Michael Just
Yeah. Thilo’s Thilo’s amazing. To be honest, one of the most passionate and driven young researchers I've ever come across. So, yeah, that's the essentially the same project. So there's two arms of the project that we manage and the drosera oreopodion side of it is the one that Thilo leads.
00:15:42:07 - 00:15:52:06
David Karsten
We'll look just on that. What, some of the species that you have found that are actually working in, in in the bushland here in Kensington.
00:15:52:08 - 00:16:13:14
Michael Just
One of the biggest challenges, with any project like this is it's the same groups that we always come up against. Things in the Cyperaceae which your little sedges and things like that. They typically put out very low amounts of seed and very poor quality seed. And then any seed that you can get, you're completely unable to germinate.
00:16:13:16 - 00:16:14:24
Michael Just
On demand reliably.
00:16:15:00 - 00:16:15:23
David Karsten
Oh how frustrating.
00:16:15:24 - 00:16:26:06
Michael Just
Yeah, it can be. But it's a good justification for more funding and for more work, so I can't complain too much. But we've had pretty good success getting a lot of these things established in the tissue culture lab that we run here.
00:16:26:08 - 00:16:27:04
David Karsten
Right.
00:16:27:06 - 00:16:42:21
Michael Just
So we have material from Kensington Bushland, but also from this site out in Byford, and using that to basically get the methodology down and then have that material available for local nurseries to draw on our collections, to then provide plants to.
00:16:43:02 - 00:16:55:09
Celeste Fourie
The Friends of Jirdarup, aim to have a thriving banksia woodland by 2043. Is this project on track to meet that target?
00:16:55:11 - 00:17:18:02
Michael Just
So I think I touched on this earlier when I said it's not so much about snapshots, but it's about trajectory. And if I was to rephrase that question, is, are the foundations in place for this to be a success by 2043? I would say yes. You know, all the right people are involved. The, the diversity and the size of the species list is increasing every year.
00:17:18:04 - 00:17:28:11
Michael Just
And we've got a good system in place for that kind of adaptive management and implementation. So without kind of backing myself into a corner with anything, I'd say it's definitely on a good trajectory.
00:17:28:12 - 00:17:36:04
Celeste Fourie
That's really positive to hear. Yeah. And and if people wanted to get involved with this project, are they still able to.
00:17:36:06 - 00:18:04:11
Michael Just
I believe the the Friends of Jirdarup Bushland, are always keen to have more members. Definitely more younger members. We do tend to see a, an older cohort come through a lot of these societies, the wildflower societies and stuff like that. And there's always opportunities for, for students to, to get involved and, and when you get involved with these societies, what you typically find is there are a lot of professionals, a lot of really interesting people in them.
00:18:04:13 - 00:18:24:14
Michael Just
And they love to give opportunities and support younger people as well. I've seen it with the Friends of Jirdarup Bushland, specifically where we've had Curtin students come through that have an interest in, you know, journalism or writing or whatever it is. And, and the Friends have recruited them in to help with their newsletters or to help with other kind of engagement activities.
00:18:24:14 - 00:18:46:02
Michael Just
So. So, yeah, always an opportunity for more people to get involved, at the community side and at the, at the friends group side. But also, I guess at the university side, we constantly have students coming through. We offer honors programs, master's programs, PhD programs as well. So for students looking to get into this environmental space, there's there's always projects going.
00:18:46:04 - 00:19:08:14
David Karsten
Michael, as a researcher, academic and and and member of staff, here at Curtin, what have you noticed in recent years about the cohorts of students that are coming through? Is there, I guess is there a a dialling up of concern? In the environmental restoration space that, you know, that this is something that needs to be addressed?
00:19:08:16 - 00:19:23:17
Michael Just
Yeah. No, definitely. I see, I see that in. Yeah, the cohorts that come through. They are typically more aware of, of what's going on in the world, and they typically have a, you know, a stronger moral compass than, than in the generations before them. And so.
00:19:23:22 - 00:19:24:15
David Karsten
We,
00:19:24:17 - 00:19:42:14
Michael Just
Yeah. So, so, yeah, most definitely, you know, and when we look at the, you know, things globally, but, but things locally with some of the, the issues that are going on, environmentally here in WA, there's definitely a big push from students to, to get involved and see what they can do.
00:19:42:16 - 00:19:51:10
David Karsten
And, I know this is such an obvious one, but was was that, I guess, a big reason that you went into the space yourself?
00:19:51:12 - 00:20:11:15
Michael Just
I would like to say so I'd like to think so. The reality is, I kind of just bumbled backwards, from, you know, one opportunity to the next path of least resistance. Always maintained a, a curiosity for, for all things. And, when, early supervisor kind of pointed me in the direction I jumped on it and thrived in it.
00:20:11:15 - 00:20:15:20
Michael Just
So, yeah, not much forward planning, but it's been really good.
00:20:15:22 - 00:20:25:14
David Karsten
You found, you found your space, and you're sharing the good word as well, which is something you've done so effectively today here on the future of and and Michael, we thank you very much for spending some time with us.
00:20:25:15 - 00:20:29:07
Michael Just
No I appreciate it, guys. Always happy to come back so much.
00:20:29:09 - 00:20:38:14
Celeste Fourie
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