The Gordon Gnohm

Play along at home, read Australia’s Cold Climate Gardening Monthly, Future Farmer. Join us now

Passive Land Hydration Pt9 Swale End Use

Let us celebrate an easier, better way to grow grass, trees and tucker. There have been 50 years of practical examples of success in marginal country all over the world. Last week we learnt how Permaculture Swales can rehabilitate degraded landscapes and can be used to accommodate grazing on pasture as one typical end use. There are other end uses for a Swale, and I will note two more to give extra scope for your creativity. 

Swales have been used to solve many growing needs and I’m sure there is a way to utilise a Swale or three on your property. Whatever you want to grow, a Swale can help by providing nutrient and water stored in the earth for your plants access. 

End Use 2 Agroforestry

I once met a chap who was big into growing trees. Timber in plantations was his thing. He didn’t grow pines. He grew high value furniture wood. He used closely placed Swales and planted them with the ‘Trinity’. 

He was referring to a set of trees he used to get the best growth for his primary money tree. His main tree was supported by two other, non-viable timber trees. Where most timber growers favour a monocrop of money trees in a paddock, he chose to grow complementary trees to assist the growth and form of his money trees. 

Laughing in the face of convention

His peers in the timber industry laughed, as he was sacrificing space and 66% of his trees were not money. But his thinking was to enhance the environment for his money trees by interplanting beneficial companions. 

He claimed superior growth throughout all the trees, not just in sections. He increased growth rates, improved timber quality and reduced the time between harvests compared to when he mono cropped.

Nurse it 

Companion one was a nursery tree, to support the money seedling for the first few years while it got established. Sometimes creating a canopy for the tree to stretch up through, creating tall straight timber. Sometimes planting to cover the area and raised the ambient temp a few degrees, all the time utilising leaf drop to provide mulch and build soil.

Feed it

The final tree was to provide habitat for nitrogen processing microbes. I’m not sure what tree he chose for this task, but it may have been an Acacia Melanoxylon. Popular and hardy in our area and of great longterm benefit to the soil and surrounding landscape. 

Plantings were triangulated, so that each money tree was in contact with both beneficial trees. He planted the Swale mound, above the trench and of course he planted below the mound to create alleys of trees, easily accessed through contour paths. 

End Use 2 Bushland Protection

I have built Swales in paddocks, but I’ve also installed them in bushland. Swaling the bush is a good way to drought proof significant trees in your landscape, bolster growth and promote deep roots. Better to maintain a large tree than let it die and plant a new one. 

Swales through the bush are also good protection against oncoming fire fronts. Pumping water from dams into Swales provides water barriers across the property. Planting fire resistant/retardant trees on the Swales furthers protection against ember attack. 

There have been many examples over the decades of Swales, simply planted with fruit trees, quelling fire fronts and saving homesteads. This is because plants with their feet in water tend not to catch fire, even Kunzea as we discovered in the 2019 fires. Swaling the bush is a much better option than clearing to grassland, as is popular for fire protection, and the local wildlife will appreciate that you left their homes intact.

Show me a Swale

I’m disappointed there aren’t more Swales in our region. When I first started outreach programs to gauge public perception of Swales, I was surprised to meet so many people who knew about Swales. I was also suitably perplexed that few had implemented them. 

One common theme kept coming to me. There was someone in the public eye telling folks Swales don’t work in our region. Wrong soil type was common, one bloke told me his rolling clay wouldn’t allow a mound to hold up on his property. 

Im not sure what rolling clay is, but the roots of plants growing in the mound will clearly hold together a fragile earth structure, as demonstrated on riverbanks. The roots also suspend the water in the soil holding it for longer than bare earth. Mulches and grounds cover can provide further protection to stabilise the surface of the mound. There is no end to the creativity and rehabilitation that can be extended by considered use of Swales no matter your soil type. 

Why aren’t they everywhere?

Some time ago, I attended a tree planting event held by our LLS, and the convener scoffed at me when I mentioned that I had installed Swales on my property. He wasn’t having a bar of it and was not interested in the benefits I had experienced. Strange behaviour by someone in a position to help, being highly educated and still showing extreme prejudice for something that has worked for farmers all over the world. 

The problem is bigger than one person trashing Swales, it appears to be institutionalised. Grant funding could be better spent on proven concepts, developed by significant Australians. Farmers can grow better with less inputs using this system. It’s important to improve…

Ill step down from my soap box now, before I really let you know what I think. Suffice to say there are reports of positive change on properties that has installed a Swale or three. 

This Week

After receiving our first frost last week, very late compared to most areas, there has been a frost most mornings since. Soil temp in newly planted beds is now 11C. The protective mulch is doing a great job of insulating the soil.

A glorious night sound has returned to the garden. The often mistaken call of the Barking Owl. You’ve probably heard it but didn’t know. It sounds like a dog. Two quick barks repeated at intervals. If you sit inside, you might think it just a neighbour’s dog. But go outside and listen as it does the rounds of your property, moving faster than any dog could run. Look out rats!

Stay Awesome.

The Gordon Gnohm

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top