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

Here’s what we’ve got for you today:

• Managing water in the city

• Acacias in Australia

• Why do we need to think about gravity

• What we’ve been learning

🔎 Looking at the Landscape

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

Steve, a past participant in our course, shared these images with our graduate community. Steve explained that Nature has something else in mind when humans build drains. This example is a constructed drain in the city tasked with removing water as fast as possible—the opposite of the mindset we should be taking when living on the driest inhabited continent on Earth.

Nevertheless, Nature has stepped in and shown excellent examples of managing water and rebuilding a landscape, but on a small scale.

Let’s discuss the first image.

Firstly, it shows how Nature is building a stepped landscape whereby the plants are building up a location to create a level spot that sits higher than the landscape below it.

Additionally, it shows one of the main ways Nature looks to slow water—by meandering it. For the first set of plants, they forced the water to come around the left-hand edge, and then the second group forced it around on the right-hand side. This movement reduces the speed of the water. It allows for more opportunities to hit itself and causes a pattern of water on water, whereby two bodies of water connecting remove the energy of the other.

The second image shows how this process, over time, allows for a landscape to be built. At that point, the plants choked the area and minimised the amount of water able to pass through, which slowed it down and allowed for the heavier sediment it was carrying to be dropped out. The sediment being dropped triggers the landscape to begin building in that location, and as a result, the same process will continue further up the system.

What I like about these images is how simply they show plants trying to restore the natural function of the landscape in a little concrete drain in the middle of the city on a micro-scale. It shows how crucial it is to learn to manage water and get plants back into our system, whether you are in the city or the country—small or large.

Steve also shared a Gardening Australia story in which they restored one of these drains into a healthy ecosystem—a great idea, but unfortunately done in a very costly way—when far simpler methods are available. Hopefully, as we progress, we can begin incorporating more restoration efforts into our cities and rural landscapes and start seeing strong positive results.

🌳 Learning from Plants

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

Acacia Family

Common Names: Wattle or Acacia

Scientific Name: The Acacia family is a large group of leguminous shrubs and trees

Where in the Succession: Early Succession Accumulator

This month’s edition will group the Acacia family, as they share many common characteristics. However, we realise there will be slight differences between species and the locations where they are growing, especially considering that there are around 1000 species within the Acacia family¹ . This will also discuss only Australian acacia species, as they have recently split global acacia species across five different genera¹ . We can focus on other species in future editions.

What is it telling me about my landscape?

Acacias are a pioneer species tasked with building a landscape capable of sustaining higher-order plant species. We categorise the acacia family as early succession accumulators, but as tree species, the condition of the landscape will determine their role and growth patterns.

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

The acacia family are a hardy, adaptable species growing throughout the country and worldwide across various landscape types.

The family comprise 8% of Australia’s native forest area and is the second most common forest type behind Eucalypt forests² .

They can often be found growing across two main conditions.

Firstly, in early successional plant communities, where they grow in high density, generally smaller in size with a shorter lifespan and often feature conditions such as;

• Bare areas

• Light, low-fertility soils

• Landscapes that have faced recent disturbances, such as fires or land clearing

• Areas that were once timbered

Secondly, in mature forests, they form part of an open woodland forest or open forest. A 2018 report found that 79% of Acacia forests are woodland forests (20-50% crown cover) and 20% open forests (50-80% crown cover), generally growing between shrub and medium trees in size.

The Acacia’s role in these two conditions is similar, but they approach it differently. We will focus on the first situation, which needs the most management and negatively affects our production as land managers.

How can we manage Acacia?

Acacias need little management as part of a diverse mix of species. However, as a pioneer species, they will most often grow in greater density and have a crucial role to play.

As landscape managers, we often find that this density of acacias goes against our productive goals. Therefore, we must determine why the acacias are growing and what we can do to assist them in achieving their goals.

An excellent place to start is by looking at the landscape where the acacias are growing. Is it;

• Very low fertility soil with little organic matter?

• Is it light sandy/rocky soil or hard compacted ground?

• Is it a landscape at an early successional stage, such as land that was once a forest that has since been cleared or burnt in recent history?

These landscapes will require you to step in and help the Acacia achieve its goals. Some ways that can be done include;

⬆️ 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 Acacia 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.

🧪 Increase soil nitrogen. The Acacia family is all leguminous, meaning they actively build nitrogen in the soil. So, if you can step in and assist them with that cause, it will shorten the time it takes them to reach their desired goal.

🌧️ Manage your water and stop the losses. A common trend across the landscapes where Acacia grows is that there is little ability for water to be held there when it rains, and 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.

✂️ Selectively thin the Acacias growing in a landscape to create an environment and opportunity for other species to grow. Ideally, this would be incorporated with the above and look to manage water simultaneously. By thinning the Acacias, we can look to recreate the landscape like it would have once been across many parts of Australia with open woodland and not dense regrowth forest like you see in many parts of the country now.

How to make the most of your Acacia

🪨 As a Soil Indicator: Low Nitrogen, Low Phosphorus, High Iron, Low Copper, Very low fertility, Very low humus, light soils

🐮 Livestock: The Acacia family can be a valuable fodder source for livestock, especially in our more arid landscapes or ones with distinct dry seasons, like much of Australia. One study found crude protein levels of Acacia to be between 11-22%, and comparing that to a minimum 8% crude protein to be the ammonia requirement for rumen microbes suggests that Acacia could form part of an adequate dry season feed mix³ . However, some species contain tannins, which limits protein availability.

One study also found that Acacia pods have a high mineral content, especially potassium, calcium, and magnesium⁴ .

💊 Medicinal: The Aboriginal people of Australia have long used the acacia family for medicinal purposes. Preparations were made from at least 30 different species of the family using a wide range of plant parts.

Leaves, branchlets, and bark prepared as poultices were used to treat flu symptoms, colds, and coughs. Ripe seed pods were used to create a soapy lather to remedy skin conditions like allergies and rashes. Long strips of the root bark were used as bandages to wrap wounds. Even for wart removal, the plant stalks were stabbed into the base of the wart⁵ .

🍽️ Consumption: Acacias have long formed part of the local Indigenous diet; however, only 47 species are currently considered edible⁶ . Diego Bonetto provides an excellent guide to identifying and consuming acacias.

The main parts of the Acacia used are the seeds, which are quite nutritious - containing, on average, 20% protein⁶ . As well as the seeds, there are the flowers, sappy gum of the bark and, of course, witchetty grubs eating the decaying timber on the forest floor⁶ .

Some species of Acacia also produce high-quality timber, which adds an additional benefit to them.

Wrap Up

This was an interesting project to try and complete a collective succession of the Acacia family. As I said at the beginning, given such a large group, there will be variability, and as we discussed, it will depend on the environment, the type of Acacia growing, and how it is growing. I wanted to share an understanding of this species’ role in our landscape and how we can manage them in a way that sees their benefit expressed and our productivity enhanced - hopefully, that has been achieved.

🙋 Answering your Questions

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

💬 Lauren Asks:

Why is managing gravity something that you discuss as highly important?

🎙️ Hamish’s Answer:

Gravity continuously removes things from our landscapes. We often associate that with what we see above the surface—water, sediment, and fertility. But it is also happening below the surface; gravity constantly leaches away our most precious resources.

As land stewards, we want to hold onto and retain as many of those resources as possible. A big part of doing that successfully is always looking to manage gravity.

To manage gravity above the surface, look to;

• Maintain an active cover of green, growing plants and minimise potential areas for water to quickly runoff.

• Implement contour structures to slow and spread water that begins moving- earth contour banks or more superficial structures made from straw and branches.

To manage gravity below the surface, we want to;

• Focus on building organic matter in the soil, as this increases the volume of water that can be held in the soil while reducing the rate at which it can move through the soil.

• Maintain soil moisture levels, as water from deeper down will evaporate through the soil when the ground becomes drier. When it rains, water will move down to replace what was lost, carrying your soluble nutrients away and out of the depth where plants can reach it.

• Incorporate trees and deep-rooted plants like our weeds, which can reach further into the soil, collect those lost nutrients, and bring them back to the surface. They both have the added benefit of managing gravity above the surface.

📚 What We’ve Been Learning

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

Dirt by Huckberry—Is Colorado a Food Utopia?: I’ve been enjoying the Dirt series by Huckberry on YouTube. It explores the local region for food and the connection with people. This episode featured a quick glimpse into some productive small farms. The series is well worth a look if you’re interested in food, adventure, or travel.

Stuart McWilliam at REGENERATE Albury 2024: TPT graduate Stuart McWilliam presented at the recent REGENERATE Albury conference. He shared his journey into learning about Natural Sequence Farming and showed some of the work he’s been implementing on our graduate properties.

Stuart Andrews: Farming that Restores the Planet: Stuart delves into the five pillars of Natural Sequence Farming, the importance of working with nature rather than against it, and the critical role farmers and consumers play in creating a resilient food system. Discover how farming can restore the planet and foster a healthier future.

Small Water Cycle Communication Grows: It’s great to see the message of the small water cycle becoming more widespread and communicated - especially when it is such vital knowledge to the restoration process.

1  Acacia: Australian Native Plants Society

2  Acacia forest - DAFF

3  Review on the Nutritive Value of Some Selected Acacia Species for Livestock Production in Dryland Areas

4  Characterization of Mineral Composition and Nutritional Value of Acacia Green Pods

5  Aboriginal Use of Wattles

6  Wattles- The incredible native to welcome spring with — Wild Plants, Foraging, Food, Art and Culture