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Whenever I’ve heard Paul Newell’s name mentioned, there has been nothing but respect from those present.

A lifetime in agricultural research and as a wheat and sheep farmer in various locations has lead Paul to be well qualified to develop ‘Landsmanship’, a practice, discipline and philosophy based on an ‘applied ecological’ approach to agriculture.

Paul’s land management approach has been described as NSF (Natural Sequence Farming, a term which he coined) without bulldozers, with biological elements skilfully utilised in time and space to reinstate landscape function to essential soil, water, vegetation and biodiversity processes, within a productive agricultural environment.

Below is a link to a paper on the Natural Sequence Farming website, written by Paul, along with esteemed ecologist, Professor David Goldney.

“Natural ecology should become the highest discipline in a farmer‘s mind. Much like the disciplines of medicine facilitate healing of the body of people we love, similarly, understanding ecology can help facilitate the health and well being of the body of land and water systems we love as our living habitat landscapes, since each farmer, so we are told, wants to leave his or her land in better condition than when he/she inherited or purchased it.”

A presentation of the practice, discipline and philosophy of Landsmanship, by Paul Newell and Professor David Goldney

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Weeping Willow

“I believe that the presence of willows along streams in agricultural zones can be shown to be almost universally preferable to cleared streams in those zones. I would also suggest that even relatively low-disturbance eucalypt-Acacia dominated riparian vegetation may not have compelling benefits over willows under many circumstances.” (Wilson, 2007)

It would be fair to presume the comment above had been made by Peter Andrews, Natural Sequence Farming originator and outspoken champion for the much maligned willow. In fact, this statement came from Dr Michael Wilson, a stream ecologist who supervised numerous PhD and Masters research projects in Ballarat, Victoria, during the early 2000s, comparing streams flanked by willows; 100 year old, multi-strata, native regrowth, and cleared land with introduced pasture.

The full paper which is linked to at the bottom of this article goes into more detail, but here’s a summary from Wilson (2007) to give you the gist:

– On average, willow-lined streams had a higher retention of sediment (187t more/km) and organic matter (30t more/km) than the native forest.

– “Willow-mediated aggradation in these channels is converting them from incised channels to in-fill channels that are more characteristic of pre-European conditions”.

Litterfall of willow and native-reveg reaches had a similar annual distribution pattern due to the not-so-well-known summer dominant leaf drop habit of many Eucalypts.

– The annual weight of leaves, twigs, bark and flowers was very similar at the willow and native sites.

– With similar annual litterfall amount and distribution, coupled with dense shade patterns in the seasons of maximum productivity, the overall metabolism (and resulting biological oxygen demand) was also very similar.

– Root mats of willows were found to provide beneficial habitat to native fish in the absence of large woody debris.

– There was a disproportionately large association between pool-riffle sequences and willows, formed by the root mats of the willows.

“Pool-riffle sequences are extremely valuable habitat and for that reason alone it is worthwhile (maintaining willows). But it becomes even more valuable when it can contribute to ideas focused on restoring the whole of the floodplain complex in agricultural landscapes.”

“In all the streams we have studied, clearing willows will mobilise sediment, nutrients and organic matter, will make heterotrophic streams more autotrophic, will threaten habitat values for invertebrates and fish and will threaten pool-riffle sequences. Native vegetation planted where willows are cleared will take many decades if not hundreds of years to mature, for the canopy to close over and for significant limb fall to occur.”

View the full article:

Click here to view the full article, Willows: Weeds of Retention 

Wilson, M., 2007. Willows: Weeds of Retention. Proceedings of the 1st Natural Sequence Farming Workshop. ‘Natural Sequence Farming: Defining the Science and the Practice’, Hazell, Peter and Norris, Duane, Bungendore, NSW,  2007. http://www.nsfarming.com/workshop/

For those who haven’t seen it, the following is a series of You-tube clips with Peter Andrews interviewed quite skilfully by Martin Royds at Baramul Stud. These clips, put together in 2007 by Paul Cochrane and the Natural Sequence Association, are one of the best overviews of Peter’s observations and hypothesis.  

Peter Andrews and Martin Royds discuss a leaky weir at the Natural Sequence Farming demonstration at Barramul Stud

Peter Andrews and Martin Royds discuss a leaky weir at the Natural Sequence Farming demonstration at Barramul Stud

(The following clips are placed in the same sequence as they appeared on the original DVD)

Peter Andrews at Baramul Stud – Introduction

Peter Andrews at Baramul Stud – Rock Walls

Peter Andrews at Baramul Stud – Weeds Pt1

Peter Andrews at Baramul Stud – Weeds Pt2

Peter Andrews at Baramul Stud – Deenergise

Peter Andrews at Baramul Stud – Floodplains

Peter Andrews at Baramul Stud – Wetlands 1

Peter Andrews at Baramul Stud – Wetlands 2

Peter Andrews at Baramul Stud – Tall Plants

Peter Andrews at Baramul Stud – Runnels

Peter Andrews at Baramul Stud – End of the flow

Peter Andrews at Baramul Stud – Erosion

In some locations with deeply incised gullies, both the goal of channel-floodplain reconnection and the goal of lateral floodplain rehydration are pretty much out of the question, at least in any way that will benefit most species on the floodplain (other than deep rooted trees).

One such example is the Natural Sequence Farming demonstration on the home farm at Mulloon Creek Natural Farms. To achieve either of the above goals would require a large engineered structure, which in a named perennial stream doesn’t sit too well with the existing regulations (extraction is achievable but would require a costly irrigation licence).

Currently, despite regulation exemptions which allowed some of the structures to already be quite large, the water level still remains 4-7m below much of the floodplain. This results in little benefit to the vegetation on the floodplain, but I believe the works have still been a success in a number of ways, one of which is setting the natural repair processes in action. (See the Mulloon Institute website for details of the research that’s been conducted)

Even during a 1 in 50 year rain event, the flow remains well below the surrounding floodplain

The locations where chains of ponds and swampy meadows existed in abundance at the time of Euro settlement, such as Mulloon Creek, are known as ‘cut and fill landscapes’.

The ‘fill’ phase referred to in ‘cut and fill’ is relatively well understood. As Peter Andrews has popularised, dense wetland vegetation choked the discontinuous channels, slowing the water flow, trapping sediment and then binding it within vertically growing root mats.

The ‘cut’ phase isn’t quite so well known. Although these systems could remain stable for thousands of years, they weren’t permanent. A natural disturbance could set a period of degradation into action, with erosion gullies cutting through the floodplain sediments. Eventually, the ‘cut’ phase stabilised and the ‘fill’ process would begin again (Johnston and Brierley, 2006).

This rebuilding phase has in fact begun in some places. Zierholz et al (2001) wrote a great paper on the process, outlining the natural establishment of instream wetlands. In some places, their study found that dense reedbeds had accumulated up to 20 years worth of sediment from the associated catchment. That is, the floor of the gully is aggrading, nutrients and sediment are being held, valuable wetland is being created, erosion is being prevented, and the main reason: lots of reeds have established.

Photo of a typical instream wetland. Up to 20 years of sediment has been trapped and stored in some tributaries in the Jugiong creek catchment, NSW (Zierholz et al. 2001)

The fine sediment has accumulated since the establishment of the instream wetlands. (Zierholz et al. 2001)

On Mulloon Creek, there are sections which before the NSF works were completed were either cut down to bedrock or basically gravel deserts, and had been that way since the degradation began, which likely occured in the early to mid 19th Century (Hazel et al. 2003). Those same sections now look very similar to the photo from the paper above.

Instream wetland forming as a result of Peter Andrews’ Natural Sequence Farming demonstration at Mulloon Creek Natural Farms. This site was down to bedrock before the works began.

What’s been the trigger? As they say, just add water:

A side profile of an incised gully, predominantly dry in between rain events

Unimpeded flow carries sediment through the incised channel

A grade control structure (or leaky weir) is constructed, causing a pool to form behind

The main flow slows as it hits the water backed up by the structure, causing sediment to deposit (halve the slope and your halve the energy)

Steel post markers put in place by Charlie Maslin on ‘Gunningrah’ show that 1.5m of sediment has been deposited at the rear of this pool. As a result of the new bar, a pool is forming in the tributary to the left of the photo

A new bar begins to form, holding moisture for longer and allowing stabilising vegetation to establish.

This bar which has formed as a result of Dimity Davy’s structure downstream has begun to stabilise with vegetation. With the exclusion of stock, Cumbungi (Typha) and Phragmites reeds are beginning to establish.

In time, retained moisture and sediment allows riparian vegetation to establish

Dense reeds are establishing at Peter’s Pond at the Mulloon Creek demonstration as a result of the pond formed by Peter’s (leaky) weir

Reeds themselves trap sediment and moisture and the bed of the channel begins to aggrade (opposite of degrade)

Universal process: Add a ‘structure’ to a gutter (a bit of spilt asphalt) and a few weeds growing from cracks and it even happens there.

Fornicating worms in the same gutter

As Craig Sponholtz of Dryland Solutions in New Mexico puts it, “This type of restoration work uses earthworks to create a foothold for natural processes. The structures then get assimilated into the ecosystem as natural healing processes take over.”

That pretty much sums up our work, so if you’re interested in helping to set nature’s repair processes into action, please contact us to discuss our design, consultancy and implementation options.

Please visit and ‘Like’ our Facebook page to hear about future posts.

Disclaimer: Where water flow is concerned there are substantial risks involved. While the information and images we publish are formulated in good faith, with the intention of raising awareness of landscape rehydration processes, the contents do not take into account all the social, environmental and regulatory factors which need to be considered before putting that information into practice.  Accordingly, no person should rely on anything contained within as a substitute for specific professional advice.

Article and Images © Cam Wilson, Earth Integral, 2012

References

Hazell, D., Osborne, W. and Lindemayer, D. 2003. Impact of post-European stream change on frog habitat: southeastern Australia. Biodiversity and Conservation, 12: 301–320, 2003.

Johnston, P. and Brierley, G. 2006. Late Quaternary river evolution of floodplain pockets along Mulloon Creek, New South Wales, Australia. The Holocene 16 (5): 661-674.\

Zierholz, C., Prosser, I., Fogarty, P. and Rustomji, P. 2001. In-stream wetlands and their significance for channel filling and the catchment sediment budget, Jugiong Creek, New South Wales. Geomorphology, 38221-235.

Gravity’s always doing its best to take your fertility to the bottom of the hill. The following images explore a couple of ways to reverse this ever-present process, hopefully bringing a more positive slant to the old saying, “Pushing faecal matter uphill”.

This is a floodplain at Baramul stud, hydrated by the Natural Sequence Farming work completed by Peter Andrews. The pasture in the foreground is obviously lush and will provide some very decent feed, however, the tan coloured biomass in the background is equally interesting

This photo was taken standing on the back of a ute which Peter directed straight through this stand of Phragmites. The scale shows the considerable biomass produced as a result of the landscape hydration

Peter had said to me on many occasions that reeds make the best compost. So one day I gave it a go and what do you know, it did (and I’ve made my fair share). This was mainly cumbungi, but I’ve had similar results with Phragmites too.

A forage harvester, baling or in the gut of a cow are a few ways of moving the material up the landscape so that the compost is useful, as Peter Andrews mentions when talking about mulch farming in Back from the Brink.

Another plant that’s synonymous with water are willows, and the more fertile it is the better they grow.

Drop a willow near stock and see what happens. Sheep will strip every bit of bark off, as they have here on Peter and Kate Marshall’s property. Their sheep come to the sound of a chainsaw, as did the stock of a few people I have met, especially during the drought. That’s the time it’s valuable and research by the Kiwis has shown that with protein levels similar to lucerne, poplar and willow can maintain lambing rates during drought periods.

Because you’re close to water, the woody material which might otherwise get in the way can be used to fill in gullies and build more fascines and brush mattresses for erosion control.

With a feed value comparable to lucerne, poplars are another tree that grow on well-hydrated land, which stock will devour. The bark is especially high in trace minerals which are mined from deep down.

There are many varieties of poplars which can be used for different purposes, Populus trichocarpa being one which also provides useful timber.

Populus alba (silver poplar) is another, this stand provides good windbreak even when dormant, while the upright form minimises shading of pasture.

Pasture grows right up to the base of most poplars. The nutrients mined from deep down by the poplars are returned to the surface via leaf drop, enriching the soil beneath.

Browse blocks are utilised by the Kiwis which if grazed often enough don’t require felling with the chainsaw.

Using a number of tyres tech-screwed together, the Marshalls are able to establish poplars while the stock are still in the paddock. A large piece of cardboard eliminates grass competition during establishment. Tyres are removed when the tree is first pollarded.

Another use for a well hydrated floodplain is cricket bat willows. These ones are inoculated with white truffle, hence the oyster shells as a free, slow-release source of calcium.

Bamboo is another plant which does a fantastic job at stitching creek banks together, the foliage providing good fodder while the poles have a huge range of uses, one of which is a good cellular structure for biochar production.

And where do the stock head when they’ve got a gut full of all this? Up the hill of course, Nature’s anti-gravity nutrient transport service. Recognising this pattern, Martin Royds has realigned his fencing to facilitate this nutrient connection between watercourse (filter zone) and hilltop.

Please visit and ‘Like’ our Facebook page to hear about future posts.

Disclaimer: Where water flow is concerned there are substantial risks involved. While the information and images we publish are formulated in good faith, with the intention of raising awareness of landscape rehydration processes, the contents do not take into account all the social, environmental and regulatory factors which need to be considered before putting that information into practice.  Accordingly, no person should rely on anything contained within as a substitute for specific professional advice.

Article and Images © Campbell Wilson, Earth Integral, 2012

The processes which existed in intact chain of pond systems at the time of Euro settlement, and those described by Peter Andrews in Back from the Brink are evident in this roadside gutter.

In this case, a ‘leaky weir’ formed (spilt asphalt from roadworks), slowing the water enough for sediment to drop out. This provided a bed for a wetland (weeds and grasses) to establish in the channel, which in turn captured more sediment, growing larger wetlands and so on.

The moisture and organic matter trapped by the wetland create ideal composting conditions and beautiful black soil begins to develop (Good enough for these two worms to decide to start a family)

When the flow is obstructed by the vegetation in the ‘wetlands’, it’s forced from the channel onto the floodplain (road). As the flow spreads and slows on the rough, well vegetated surface (blue metal chunks), bulk biomass and fertility from the wetlands is deposited. Here, the biomass has accumulated on contour, similar to this other post.

 

Copyright Cam Wilson, Earth Integral 2012

When building natural capital (including beef or wool), increased potosynthesis is the goal of any land manager. Available moisture is, of course, a key factor.

At the time Europeans settled in South-Eastern Australia, many broad upland valleys were described as chains of ponds or swampy meadows. There are a few of these well hydrated, very productive systems, effectively drought proof systems still remaining (for example the Hazell’s property), but the majority have been severely eroded and subsequently drained (click on the following for an outline of the degradation process, in diagrams or the scientific literature).

At Tarwyn Park, Peter Andrews demonstrated the potential primary production benefits from reinstating the original floodplain processes and rehydrating the surrounding landscape.

One way of doing so is by raising the alluvial water table through lateral infiltration (as described in the post Floodplain water storage). The speed this occurs depends on the soil type, but if it’s going to happen any time soon the main driving factor is a fairly constant supply of water from the catchment above.

High in the landscape, inflow from the catchment above is generally only available for a short period of time. Where this is the case, the effectiveness of relying solely on a lateral hydration approach is limited, as a severely drained landscape will take a considerable time (maybe several lifetimes) before the water table is raised high enough to enhance plant growth on the floodplain.

Where short sharp bursts of runoff are available, the fastest return can be achieved by reinstating the old flood flows. Water spreads out across the landscape once more, soaking into the floodplain for the extended use by the plants and soil life. Sediments are also deposited, the process which has made floodplains the rich production zones they are worldwide. Basically, it’s recommissioning nature’s flood fertigation system.

In an intact landscape, there are predictable locations where floodwater is more likely to top the banks, just as there are locations where it’s likely to re-enter:

On a macro-scale, floodplain flow patterns are often closely related to the ridges intruding into the floodplain (Tane, 1999)

Where multiple ponds exist between the major landscape features, braided flood flows (red arrows) generally exit the downstream half and enter the upstream half of a pond (P Hazell, personal conversation)

When siting structures, an understanding of these processes is the key to getting the most bang for your buck. A structure in an inappropriate location may get the water up onto the floodplain, but it will soon spill back into the gully, maybe even worsening the existing erosion. In contrast, a well positioned structure results in the flow heading away from the watercourse, spreading into a more passive flow and hydrating the floodplain surface before re-entering the stream sometimes hundreds of metres downstream.

On Gunningrah, Charlie and Anne Maslin have sited their structures as well as anyone I’ve seen with this goal in mind. Having taken inspiration from Peter Andrews on ‘Australian Story’ and attending a Natural Sequence Farming field day, Charlie has since constructed around 40 leaky weirs on Gunningrah (For more information about the Maslin’s farming prowess, see their profile in the Soils for life case studies).

There are a range of positive results which the Maslins have achieved depending on the landscape position of the works, but the following couple of examples are a good demonstration of utilising the original flooding processes mentioned above.

(Note: To avoid hefty fines, it’s important to adhere to local watercourse regulations. In many places there are few restrictions on ‘dam walls’ within first and second order streams other than the harvestable rights of the property)

Poplar site

Flow had become contained within the incised channel, taking shortest path it could towards the ocean. The only moisture available to the surrounding floodplain was what fell from the sky

An earth wall structure intercepts the flow in the channel, reconnecting it with the floodplain. The flow re-enters more than 500m downstream, with the potential to irrigate about 6 ha of pasture.

The poplars indicate the path of the incised channel, the flow now spreads out across the floodplain

Looking upstream at the same structure, the flow spreads significantly across the paddock.

Debris in the middle of the paddock, around 50m from the main channel.

Hayshed site

Flow path before the works….

….. and afterwards, back to how it once was

An aerial view of the flow before the works were completed, contained within the incised channel

An earth wall intercepts the channelised flow, spilling onto the surrounding floodplain. For an idea of the extra water harvesting potential which results, 0.25 Megalitre is stored for every 25mm of water that’s accepted by the landscape per hectare. A healthy topsoil can receive far more than that.

In case you’re still wondering “How can water flow away from the main watercourse? Isn’t that always the lowest point?” It is in a young landscape, but Australia’s pretty geriatric as far as watersheds go.

In Back from the brink, Peter Andrews talks about water flowing on the high ground (of the floodplain). This phenomena was observed by plenty of early explorers and it’s also well accepted in the scientific literature. In short, when a watercourse spills its banks, the water slows down, depositing the heaviest sediment. In time, a natural levee is built as seen below.

If you’re interested in getting these processes happening once again on your land, contact us to find out about our design, consultancy and implementation services.

Please visit and ‘Like’ our Facebook page to hear about future posts.

Disclaimer: Where water flow is concerned there are substantial risks involved. While the information and images we publish are formulated in good faith, with the intention of raising awareness of landscape rehydration processes, the contents do not take into account all the social, environmental and regulatory factors which need to be considered before putting that information into practice.  Accordingly, no person should rely on anything contained within as a substitute for specific professional advice.

Article and Images © Cam Wilson, Earth Integral, 2012

References

Tane, H. 1999. Catchment Habitats and Landscape Ecosystems. Centre for Catchment Ecology, 1: 1-12