Good morning, and welcome to the tenth edition of our monthly newsletter, Reading Landscapes.

Here’s what we’ve got for you today:

• What’s a gilgai

• Managing Drooping Cassinia

• Can I implement contours on a small scale

• What we’ve been learning

🔎 Looking at the Landscape

Like us to discuss a photo of your landscape? Share it with us here. 

Last week, we travelled down to our property in NSW. This meant travelling west from Forage Farms through the western downs region of QLD and a large part of the grain-growing region.

An area full of a specific landscape feature known by many names… Gilgai, Melon Holes, Crab Holes.

Some of you might be thinking, what are they? As Mr. Wikipedia says, Gilgai is “a small, ephemeral lake formed from a surface depression in expanding clay soils”² . It gets its name from an Aboriginal word meaning small water hole.

As you can imagine by looking at the paddock below, these formations make the road rough, but what made me think about writing about this wasn’t at first the bumping, bouncing, rough roads between Dalby and Moonie. It was looking out across the paddocks that the harvester had just been through and seeing the ups and downs that it faced as it harvested the wheat.

These landscape features are most prominent in Australia but also found in Central Russia and some states of America.

What caused all of these patterns and the uneven paddock? And why are they there?

Well, they’re natural undulations found across swathes of Australia - in our inland areas, and they are the natural recharge function of these landscapes. Put simply, each minor depression acts as a mini wetland for that landscape - a place to slow water down, infiltrate it into the ground and create an area from which the local ecosystem can be powered.

They work in unison with the cracking clay soils of these landscapes so that when a rain event occurs, the water is slowed down and allowed time to be slowly absorbed into the heavy clay soils without being lost to runoff. They are nature’s buffer to stop runoff.

They are a challenge for farmers, particularly crop growers, and, in many cases, our management can remove their natural infiltration abilities.

So, how can we assist gilgais in our landscapes? One fundamental way is through contouring; instead of having little mini wetlands across a landscape, regular contours can slow the water down and hydrate the heavy clay soils.

In non-cropping operations, the most straightforward approach is to learn to understand the role of gilgais and leave them to complete their role. Implementing contours can support them, particularly in landscapes where this natural process is no longer functioning as it once did.

As I bounce along on these rough roads, I write this understanding of their critical role in the Australian landscape.

🌳 Learning from Plants

Have a plant you’d like to discuss? Share it with us here.

Drooping Cassinia

Common Names: Biddy Bush, Sifton Bush, Chinese Scrub, Coffee Bush, Tear Shrub

Scientific Name: Cassinia arcuata

Where in the Succession: Early Succession Accumulator

This month, we will be looking at Drooping Cassinia. Thanks to Gregg for sharing this month’s species.

What is it telling me about my landscape?

Drooping Cassinia is an early succession accumulator often found in early successional landscapes with low soil fertility and conditions that are too tough for higher-order species.

Where will I find Drooping Cassinia growing, and why is it growing there?

Drooping Cassinia is a hardy, early successional species ideally suited to growing in harsh conditions, making it an ideal pioneer species, finding itself growing in;

• Low-fertility, light soils

• Shallow, stony soil

• Sandy soils

Other environments that Cassinia often finds itself growing include;

• Cleared landscapes that were previously timbered

• Bare, disturbed areas like roadsides, ex-mines and gravel pits

• Post-fire environments

• Within dry woodland forests, as an understorey

How can we manage Drooping Cassinia?

As we can see from the conditions that Cassinia is often found growing in, as we discussed above, in most cases, as land stewards, we will need to step in and assist Cassinia in achieving its goals.

Some of the ways that we could look to do that include;

✂️ Selectively thin the Drooping Cassinia or slash them; doing so adds their biomass to the surface as fertility and creates an opportunity for other species to grow. Ideally, this process would be incorporated into managing your water.

Interestingly, a study in the 1970s looked at slashing as a management technique for the plants and determined the following key suggestions⁴ ;

• The effect of slashing was most severe on plants taller than 1m, with only 1% of plants surviving 10 months after slashing

• A vigorous pasture species was established to compete with the Cassinia after slashing. In this experiment, they used Subterranean Clover

⬆️ Look for ways to increase soil fertility and organic matter so that higher succession plants can survive and thrive. This could consist of bringing in external sources of fertility such as mulch, manure, compost and the like. It could also involve mulching some of the Cassinia and using it as organic matter for the soil. The key is to get that soil-building because, with improved soil, you will see an enhanced plant succession.

🌧️ Manage your water and stop the losses. A common trend across the landscapes where we see Drooping Cassinia growing is the limited ability for water to be held there when it rains. In turn, fertility, nutrients and sediment are not managed either. Stepping in and trying to hold on to those things by implementing something like a contour will be a big step forward in improving the functioning of that landscape.

🪨 Build the soil. Cassinia is a pioneer species and thrives in landscapes with poor-quality, often acidic soils. By implementing the steps above, you focus on improving that landscape and ultimately creating a higher-quality soil capable of hosting the higher-order species. In Nature, this process can take a long time, but we can speed that up by getting in and lending a hand to achieve the results we’re after.

How to make the most of your Drooping Cassinia

🪨 As a Soil Indicator: Very low fertility, very low humus, light soil, acid soil

🐮 Livestock: Drooping Cassinia has low palatability to livestock and has been suspected of poisoning in lambs⁵ . Goats don’t readily graze it but will eat young plants and leaves while substantially impacting more mature plants at higher stocking rates.

💊 Medicinal: The plant has no known medicinal uses.

🍽️ Consumption: There is no objective evidence of the plant having any edible uses for humans, but interestingly, it gets the name Chinese Shrub from Chinese miners and early settlers using the plant as a thatch for roofs⁵ .

🙋 Answering your Questions

Ask the Team! Share your question here, and we’ll answer it in a future newsletter.

💬 Emma Asks:

What if I’m on a small piece of land and don’t have the means or need to build contours with large machines? How can I go about managing my water with the same principles?

🎙️ Hamish’s Answer:

That’s an excellent question, Emma.

There are many small-scale ways of recreating the contouring process without getting into the big machines. The only real change will be the volume of water that can be managed.

A few methods you could look at include;

• Creating contours out of straw and mulch by spreading the material across a level line. They will absorb the water, slowing it down, and as they break down, they will do the double task of spreading their fertility. You can keep topping them up with more material as they break down. These can also be created using whole small square bales.

• Creating mini contours with a hoe and shovel instead of with machines

• Stick or brush contours are another option for managing water across a landscape

These are some quick and easy methods to implement. In the long term, they will not yield the same result as a contour made of earth, but they are a great place to start and work well in smaller landscapes.

This statistic is insane and pushes the need for a constant green surface area; why? Nature created plants to manage that heat and energy, and so far on Earth, they are by far the most efficient at managing the sun’s energy. In landscapes without green-growing plants, that heat is reflected back into the atmosphere, heating the local climate, whereas if plants were present, they would manage that heat.

📚 What We’ve Been Learning

A quick list of our favourite things we’ve been watching, reading, listening, and writing.

Stockman Grass Farmer—I recently subscribed to the digital edition of Stockman Grass Farmer from the U.S. and have enjoyed their monthly paper, which covers various topics across all regenerative spaces. It is a good investment in your learning.

Contours in Action at Ripple Farm—Look at the effect of the contours we implemented at Ripple Farm. Tasmania has had a tough season lately, and the contours are helping to maintain a green surface area. We will be heading down to Tasmania next year for anyone in the area wanting to learn how to build their own contours.

J&L Green Farm Tour—I love watching farm tours on YouTube, and the videos put out by Heifer Ranch are always great. This tour of a multi-species farm is well worth a look. Another favourite of mine was his creation of some tremendous wooded pastures using silvopasture ideas.

197: Kit Pharo—Unexpected DNA Results—I listened to this interesting podcast on the Ranching Returns channel this week. It discussed some new DNA-based traits that PCC is testing for in its bull program.

1  Denise McLellan \(@DeniseAMcLellan\) on X

2  Gilgai

3  Gilgai Wetlands

4  The effect of slashing on Chinese Scrub

5  Cassinia arcuata

6  Amount of Solar Energy Hitting Earth Every Second, Day, Week & Year