This guest post is by Dr Jess Drake. Jess is writing this series in her spare time because she wants to freely share some proactive ways for people to manage the effects of climate change.
I have always wanted my own native garden, full of beautiful and diverse native plants. Rocks and logs for habitat. Reptiles and birds hanging around for food and sanctuary. And now I am in the planning phase of just that.
My first thoughts have always been a local endemic native garden. One that attracts local wildlife, is suited to the soil and climate, and is water smart. Thinking about this, as well as my desire for living as sustainably (e.g. grow our own food), I got to thinking about planting out my entire front yard with local endemic natives that also have human uses for food, fibre or medicine – having a go at cultivating my own bush use garden!
Indigenous use of plants
Bruce Pascoe has written a fabulous book ‘Dark Emu’ which draws together the evidence on the indigenous cultivation of plants, particularly grass species and Murnong (Yam Daisy) in Victoria. Did you know there were plains and plains across volcanic Victoria full of cultivated murnong?? Amazing! He is doing some fantastic work in the Bega and Gippsland regions with Gurandgi Munjie Food Company on bringing back the traditional cultivation of a range of native grass species—and baking bread!
Beth Gott has also worked on researching first nations use of Victorian plants, and her work is widely used among plant ecologists. You can find an example of her work on The Conversation and Trove. I was inspired, particularly by Bruce, to try and cultivate some of these plants myself, and to bring back some of the healthy landscapes that was here prior to European invasion.
I am lucky that our local nursery has been propagating some of the species that Beth and Bruce discuss, and that are known to occur locally*. In fact, the nursery even had local provenance within the general Castlemaine region. That means I can plant out a local bush use front yard!
This winter, I got organised and decided to start planting out part of the yard with these local species:
Murnong, Blushing bindplant, Blue Grass Lily, Magenta and Austral Storks Bill, Small-leaf Clematis, Native Flax, Inland pigface, Sweet Appleberry, Showy Podolepsis, Variable Glycine and Ruby Saltbush.
The Ruby Saltbush is actually all through my backyard, which is a great sign it will do well. And I plan to add more species and trees over the next few years, including a big native grass patch and ample Murnong! I want to have a diverse and complex front yard that considers a range of tree and understory species, but where everything has a human use and ecological one too.
I felt pretty pleased with this start. It is sustainable-thoughtful of the local environment, and requires low water use. And it will be useful for us and still provide habitat for insects, birds, and other native animals. That was until a week ago when I saw a talk on plants and climate change. I thought I had considered climate change by planting a native garden, but I failed to think about the natural range of species.
Plants and climate change
Connecting Country hosted two separate talks on climate change in revegetation and weed control. I went to both talks when they were held in Castlemaine.
As a soil scientist I don’t have a lot of experience in the ecology aspect of the environment—I tend to think of plants in their connection to soil and ecosystem function. The talk on revegetation, however, focused on ecology, plants and climate change, discussing how plants at their edge of their natural range will start to die out with climate change-within the next few decades.
We need to consider this in all revegetation projects.
The three speakers (Jeroen van Veen, Sacha Jellinek and Brian Bainbridge) all discussed their various projects, but they all had similar take home messages:
· Need to think about the likely CSIRO climate change prediction for your area
· Need diversity of species in revegetation
· Need to consider that there are plants covering all ecosystem functions
· That we need to think more broadly about provenance of species
In practice this means that people undertaking planting should think about what the climate will be in the area in 2035 and beyond. For Castlemaine, it will be a climate more similar to Dubbo—you can look up your future climate at Climate Change in Australia. This means we can look at a climate analogue, and hence an ecosystem that is closer to what is in Dubbo when we think about Castlemaine.
To start, the speakers discussed that you need to build up a diversity of species that will be resilient to change and extreme events like fire, flood and drought. This is all pretty normal for planning revegetation, until you think about the climate in Dubbo compared to the climate in Castlemaine now – Dubbo is hotter and drier. That means that any plants that are here in my area now and are on the edge of their tolerable range, may die with the change. And what will replace them?
This is where the speakers talked about provenance and ecosystem function. All speakers talked about the provenance of local endemic species being from hotter and drier climates where possible. For example, seed for species found here and closer to Dubbo should be sourced from Dubbo in conjunction with local seed. They suggest that the plants from the climate analogue (Dubbo) will be more genetically adapted to the conditions we will be facing. When introduced with local provenance, they will start cross-breeding and hopefully build resilience.
In some cases, finding a different provenance of a plant may not be possible. The speakers suggested that the plant may be on the edge of its range already and a different provenance is therefore not possible. In these cases, they suggest introducing a new species that replaces the ecosystem function of the species that will/has been lost. This is much harder to do than simply sourcing seed from a more arid climate, and it's hard to write guidelines for the speakers said. However, Brian said that Merri Creek Management Committee has started to do this in their Bull Mallee plantings, which are analogues of Bull Mallee found near Bacchus Marsh and in western Victoria.
Sacha from La Trobe and Greening Australia is working with a team on Victorian guidelines for revegetation considering climate change. There will also be national guidelines released later this year.
After this talk, I realised I have to go back to the planning phase for my bush use front yard.
What am I going to do?
With this in mind, I need to think about a few things:
Diversity and complexity
I still need to have herbs, forbs, tubers, grasses, shrubs, trees etc. My old plan still works here—building diversity! I just need to augment provenance and species to be suitable for the predicted change.
Provenance
What of the local species are known to survive in the hotter drier conditions around Dubbo? Can I get plants or seeds from this area? Kangaroo Grass was traditionally used for food and fibre, and is endemic to both Dubbo and Castlemaine. Now I need to see if I can get some seed from a nursery around Dubbo.
Introducing species with functions
What other species can I introduce that are known to have human use and ecological value, and are in hotter drier climates in Australia? Old Man Saltbush is known to occur in dry western parts of NSW, and could be a great shrub species to add to the garden. It will provide habitat to animals and herbs for us, hold soil together with its deep-roots, and is great for drought susceptible environments where it likely helps to retain moisture in the environment.
Now to go and do some more research. I will let you know what I end up planting!
* My local Nursery used these resources for their indigenous use native plant list: AB & JW Cribb’s “Wild Food In Australia” and “Useful Wild Plants In Australia”; Tim Low “Bush Medicine”; SGAP Maroondah, Inc “Flora of Melbourne”; N Zola & B Gott “Koorie Plants, Koorie People”.