Recreating the Country blog |
The Grey Wolf Introduction by Stephen Murphy Many of us are familiar with the remarkable story of the Grey Wolf and Yellowstone National Park in Wyoming, U.S.A. The last wolf was killed in the park in the 1930's and this opened the way for the Yellowstone Elk to breed unchecked without its natural predator. Their grazing patterns also changed and the elk began camping over winter where it could brows on young willow, aspen and cottonwood trees. The loss of the trees then affected the life cycle of the beaver, a critical species supporting the parks riverine ecology. The shrinking biodiversity of the park was on the verge of collapse, when in 1995 a remarkably brave decision reversed this pattern of decline. A pack of wolves was released into the park as the world watched in disbelief. Nearly thirty years since their return, the wolves have brought about many unexpected benefits including the recovery of the beaver. 'Wolves are causing a trophic cascade of ecological change, including helping to increase beaver populations, bringing back aspen and other vegetation.' Adopting a similar strategy in Australia and returning our largest predator, the Dingo, Canis lupus dingo, to National parks and reserves would likely have similar benefits. A study lead by Associate Professor Mike Letnic noticed vegetation differences on either side of Australia's 5,614 km long Dingo fence. On the Dingo side there are fewer kangaroos and more small mammals because foxes and cats are controlled. This also resulted in a greater diversity of vegetation. A CSIRO study found greatly reduced populations of larger kangaroo species and feral goats, which were a major factor in landscape degradation, across large areas of Australian rangelands in Queensland and Western Australia. The study also found that cattle growers who encouraged dingoes had increased profits and no predation of calves by the Dingo. Professor Euan Richie explains the benefits of reintroducing both the dingo and the Tasmanian devil to mainland Australia in his excellent article below: From the dingo to the Tasmanian devil - why we should be rewilding carnivores. Thank you to guest blogger Euan Ritchie who first published this great article on rewilding carnivores in The Conversation in February, 2023. Euan is Professor in Wildlife Ecology and Conservation, School of Life & Environmental Sciences at Deakin University. Reintroducing predators - do the benefits out way the risks? No matter where you live, apex predators and large carnivores inspire awe as well as instill fear. Large predators have been heavily persecuted and removed from areas where they once lived because of conflict with livestock graziers. Beyond their large teeth, sharp claws and iconic status, research is finding they are crucially important in ecosystems. So there is considerable interest in returning large carnivores to areas where they once lived, as part of a shift towards rewilding. Bringing back carnivores is not without risk, but it’s a potentially powerful conservation tool. Rewilding dingoes and Tasmanian devils in Australia could benefit many of our troubled ecosystems, by keeping herbivore numbers down, keeping feral cats and foxes fearful, and triggering a rebound in vegetation and small animal populations. Predators vs prey Predators can affect their prey’s behaviour. When prey species know a predator is around and perceive risk to their survival, they change how they behave. The landscape of fear predators create can make it harder for prey species to survive. That’s often good for ecosystems. The effect of dingoes in reducing, say, kangaroo and wallaby populations and changing their behaviour, can actually help bring back plants and smaller animals through a “trophic cascade”. For example, wolves chasing, eating and scaring deer can lead to an increase in the growth of plants, which can benefit other species. Predators also affect other predators. If humans poison, shoot, trap and exclude top predators like dingoes, smaller predators can increase in number and get bolder, in a phenomenon called mesopredator release. In California, when coyotes disappeared due to habitat destruction, populations of smaller predators such as cats grew and songbird numbers fell. How is it done? Rewilding can occur passively, by changing laws to stop the exclusion or killing of large carnivores and making areas more favourable for carnivores to live. When this happens, species often move back by themselves. Encouragingly, this is happening in many parts of the world, including a recent sighting of a wolf in Brandenburg, Germany. In other cases, rewilding may need a more active approach, such as physically moving animals to an area. The return of wolves to Yellowstone National Park and the ecological transformation that followed is a famous example of this, although in recent times the details of this story have been questioned. When does rewilding work best? Recent research shows wild-born animals fare better than captive-born animals, though the results are far from conclusive. Wild-born animals may have an edge due to their skills in hunting and defending territories critically important for survival. Rewilding in Australia means bringing back dingoes Once carnivores are killed or fenced off from an area, the ecosystem changes. Will we restore nature by bringing them back? Potentially – but it’s not guaranteed. Australia’s controversial canine, the dingo, is a perfect example. Aside from humans, dingoes are Australia’s only living land predator over 15 kilograms. Dingoes have a vital role in Australian ecosystems, such as keeping populations of kangaroos and emus under control. They can also take down feral goats. Their natural control of herbivores means plants can bounce back, as well as making room for smaller animals. Their effect on plant life may even affect the height and shape of sand dunes. In some parts of Australia, kangaroo populations have exploded. Land clearing for pasture favours kangaroos, as do the dams and water troughs for livestock, the killing off of dingoes and the ending of First Nations Peoples’ cultural practices and hunting. At times, these population booms have led to sudden crashes, with widespread starvation in droughts. Harvesting kangaroos is one response, but this is often controversial and unpopular. Bringing dingoes back would help reduce kangaroo numbers in a way more palatable to many people. When present, dingoes also keep a lid on our worst introduced predators, feral cats and foxes, either by eating them or forcing them to alter their behaviour. If cats and foxes have to be more careful, it may benefit their smaller prey. We could rewild dingoes very easily by removing large barriers like the dingo fence. This, of course, would trigger pushback from livestock graziers worried about attacks on their stock. It doesn’t have to be this way though. We’ve learned a lot about ways to reduce conflict between farmers and predators. It’s now entirely possible for livestock producers and top predators to coexist. Western Australian farmers are already using guardian animals such as Maremma dogs to protect livestock. So should we do it? Australia has been slow to support and attempt large carnivore rewilding. But we can learn valuable lessons from the relocation of Tasmanian devils to an offshore haven, Maria Island. Devils were introduced to safeguard the species against the severe population decline from devil facial tumour disease. These predators were not native to Maria Island, but they’ve flourished. One unexpected side effect was the devastating impact on the island’s little penguin population. Rewilding comes with risks. But it also comes with major benefits, which may help our collapsing ecosystems and threatened species. Time is short. Conservation must take calculated and informed risks to achieve better outcomes. Rewilding attempts are valuable, even when things don’t go entirely as planned. What else could we do? Discussions over the carefully planned reintroduction of Tasmanian devils to mainland Australia continue. If the devils come back to the mainland for the first time in thousands of years, they might help to manage herbivore and feral cat populations. Rewilding is not about recreating the mythical idea of wilderness. Humans have shaped ecosystems for millennia. If rewilding and ecological restoration is to succeed, communities and their values, including First Nations groups, must be involved.
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Turning the tide - time for a grasslands revolution You’ve received a mysterious invitation from a close friend to a grassland party. ‘A what? You think – that’s quirky!' When you arrive, you’re greeted at the door by your very excited friend, who ushers you into her lounge where four other women from your preschool group are seated. You give one of them a quizzical look. She raises her shoulders as if to say, ‘search me?' Your friend claps her hands and says excitedly, “Ladies, you’re here to share in my new passion. You’re here to help me turn back the clock 180 years. You’re here to help me plant my grassy back yard into a low maintenance, wildlife friendly, carpet of beautiful, local wildflowers.” Does this gathering of young mums sound feasible to you? Could restoring indigenous grasslands in backyards capture the enthusiastic support of Australians from all walks of life? Is it possible to start a revolution that would see indigenous grassland plants return to the streets and gardens of our nation? The carbon sequestration benefits of planting millions of deep-rooted perennial plants would be reason enough to support a grassland revolution. If you're worried about the continuing disappearance of our grassland flora and fauna, you would probably agree that a significant challenge is to develop relatively uncomplicated methods of restoring native grasslands that can be applied on a small or a large scale. This would empower more land managers, including young mums with small backyards, to restore indigenous ecologies on a variety of Australian landscapes. It is an intriguing challenge that desperately needs some serious thought and some practical solutions. What follows in part 3 of Restoring Native Grasslands is a catalyst for discussions about how this restoration could be done. Part 1 of Restoring Native Grasslands, looked at the history of grasslands in Victoria and how our landscapes have changed since settlement in 1835. Part 2 of Restoring Native Grasslands looked at some larger-scale restoration success stories and what can be leant from them. Grassland plants fight back – in a nutshell; Your mission - to plant an island of grassland plant champions and then get them through their first year.
Blow by blow - in bruising detail: 1. Plant islands of indigenous plant champions. Bellarine Landcare’s Grasslands Interest Group has put together a list of very hardy local grasses, lilies and herbs that are capable of going head-to-head with weedy interlopers. (Thank you also to John Delpratt and Stuart McCallum for your contributions to the list of grassland champions) Grassland Champions list: The Grassland Champion’s list presently includes 76 species, from 50 genera, and 22 families that are found in central Victoria. This list can be extended with other hardy indigenous plants which are local to your area. When the champions begin to take control and improve the soil chemistry, other less hardy plants can be added. The list is in the form of a table that includes other useful information. Click here for the table Always include some nutrient strippers in your plant list. Nutrient stripping plants like Kangaroo Grass will help maintain lower nitrogen (N) & phosphorus (P) levels in your island planting. Plant in groups/clumps of the same species - 10 to 50 plants/clump is ideal. Plant smaller species in larger numbers so they can dominate their given area. See the champions table for the recommended spacing for each species Why plant in same species clumps? Planting in clumps looks great, is nature's way, attracts more pollinating insects and will produce more fertile seed, giving the grassland champions the greatest likelihood of spreading into surrounding areas. 2. Choose the best place to plant the champions. Look for helpful indicators of where indigenous plants will best grow. Plant near remnant grassland plants:
Read more about identifying native grasses here Choose the best soil for native plants:
3. Avoid planting near invasive weeds like Kikuyu, Couch, Phalaris, Paspalum and Oxalis. These are dominating and destructive perennial weeds that are best managed with an application of herbicide. Ideally follow up with a cool burn when they die and spray with herbicide again if they reshoot. Show them no mercy because they will take over the grassland and destroy all your good works. Once they invade they are much harder to control. Using this process, you will systematically eliminate difficult-to-manage weeds, though it is likely to take two growing seasons. Planting grassland plants before these tough resilient weeds are banished, will only result in disappointment. A note on spraying with glyphosate: Herbicide is a useful tool if it is used safely and intelligently. The time to spray is when the weeds look healthy and are showing strong growth up to 10cm tall. Allow more top growth before spraying deep-rooted weeds like Phalaris and Paspalum. (See pictures below). Kikuyu and Couch grasses die back naturally in winter, so spraying at this time does them no harm. It is better to spray these weeds in late spring or early summer when they are growing strongly. Oxalis is best sprayed at the beginning of its flowering cycle when the plants have just a few flowers. Spraying at this time will kill the many small bulbs (future plants) that are attached to the oxalis roots. My personal story. As an organic vegetable grower, I have tried hand-weeding these difficult weeds year after year. This involved putting the soil through a sieve to remove any potential growing shoots or bulbs which is a slow and tedious process. Yet, still the problem weeds kept coming back. I swallowed my disappointment and applied one well-timed spray with 1% glyphosate, the recommended rate for difficult-to-manage perennial weeds, and eliminated them. To put this spray-rate into perspective; 1% is equivalent to spraying 1 teaspoon of glyphosate concentrate over a 25 square meter area of perennial weeds. The remarkable environmental benefits gained from establishing 5m x 5m of healthy native grassland clearly outweighs my environmental concerns about the use of glyphosate. Nutrient stripping – a big blow to the weedy interlopers: Reverse fertilisation.
Burning the stubble when it dries will further lower N & P levels and adds smoke chemicals to the soil that enhance the germination of many native seeds.
Planting scattered canopy trees at a similar density to the original pre-settlement spacing will create an open grassy woodland and lower soil nutrient levels. This nutrient lowering effect has been observed to extend at least 1.5 x height of canopy trees from their trunk. Therefore trees reaching a mature height of 20 m will lower soil nutrient levels up to 30 m from the tree’s trunk. Planting nine, 20 m tall canopy trees over one hectare will eventually return the soil nutrients to a pre-settlement lower levels. (This density was calculated on an average spacing of 30 m between canopy trees). Note on planting canopy trees: Canopy trees planted in groups of 5 trees (tree spacing of 3m within these groups) has many advantages:
Planting clumps of shrubs. An alternative design is to include clumps of indigenous shrubs and understorey trees. This will diversify the sources of food and improve habitat for wildlife. To lower soil nutrient levels, the shrub-clumps and the clumps of understorey trees are spaced at 1.5 times their mature height. Therefore, a clump of twenty, 5 m tall shrubs, will lower soil nutrients 7.5 m beyond the outer edge of the clump. A clump of 10 understorey trees with a mature height of 12 m tall, will lower soil nutrients up to 18 m beyond the outside edge of the clump. Within these clumps, the plants are spaced at 2 – 3 m. In this way, a mixed shrubby woodland with grasslands in the open areas could be restored over 1ha of over multiples of 1ha. Making compost teas. Microbe-rich inoculations have been shown to stimulate the revival of some grassland species. Microbe-rich teas can be made from worm-juice, compost or manure. A concentrated tea is made by harvesting worm juice or by placing a permeable bag (e.g. hessian) containing about 9 L (one full bucket = 9 litres) of compost or manure into a 150 L drum of water (40 gallons). (These volumes can be scaled up or down to suit the size of your project). After one week, the microbe-rich water in the drum is diluted to the colour of weak tea and sprayed over the grassland plants. This is best applied when the soil is moist, on a cool, cloudy or rainy day, in mid-spring or mid-autumn. Direct sunlight will kill the microbes in the tea. The benefits of inoculating with microbe-rich teas is discussed in; Restoring native grasslands - part 2 Spreading out from the island plantings Paul Gibson-Roy and John Delpratt noticed grassland plants spreading well beyond the edges of their restoration sites; “At all Grassy Groundcover Research Project restorations, native grasses had colonised some tens of metres beyond the boundaries of the original restoration zones and at a large number of sites, forb species had also expanded beyond the restored area” (Paul Gibson-Roy and John Delpratt. 2015. Land of Sweeping Plains. Chapters 11 & 12.). When the island planting is established, the exotic weeds growing around the fringes of the island are your next frontier to conquer. The techniques discussed under ‘Nutrient Stripping’ can be used to expand the island planting:
...the backyard planting
About two years had passed since the grassland party and Cathy was surprised at how well her family had adapted to the new backyard. Instead of a regularly mown grassy patch, it was now a accidental meadow with a mosaic of colour. Her four-year-old loved running through the wildflowers and watching the white and brown butterflies flutter into the air around her. There was something wonderful about seeing a carefree child, arms raised, eyes looking upwards, red curls twinkling in the sun, following the silent random flight of the fluttering butterflies. Reimagining native grasslands. The native grasslands that we have inherited, have been radically changed; by hotter fires, intensive grazing and clearing for cropping. It is likely that there are no examples of the original mix of diverse grassland plants remaining in Victoria. A sobering thought perhaps, though it does provide the opportunity to reimagine Victorian native grasslands and to invent practical methods to bring them back to our urban and rural landscapes. Restoring grassland would be a powerful way to lock-up tonnes of carbon and it would restore habitat in the form of grasslands and grassy woodlands for our endangered plants and animals that depend on these disappearing ecosystems. The clock is ticking and the time for action was yesterday! In Part 2, I explore what we can learn from the people and scientists who have been successful at bringing back native grasslands. In Part 3, I outline a low cost and adaptable method that could be used to restore grasslands at a small or a large scale. (Coming in December) Farmers are now beginning to see the benefits of protecting native grasslands. Restoring native grasslands and grassy woodlands is a significant challenge that many of us have pondered. There is now a groundswell of scientists and land users who recognise that farming practices developed for the UK and European climates and soils are unsuitable for the fragile soils and more arid conditions in Australia. This has given rise to the practice of Regenerative Agriculture, which protects native perennial grasses by working with their natural growing cycles. Though, the native grasslands surviving on private property have endured generations of farmers who didn't protect or value them, so these grasslands are likely to be composed of the few resilient survivors that are less palatable to sheep and to cattle. They are likely to be just a shadow of the plant diversity of grasses and forbs, described earlier in Restoring Native Grasslands - Part 1, as ‘herb rich pantry-lands’ or ‘medicinal herb-lands’. Irrepressible nature - The Winona story It is astonishing how irrepressible our native plants are. Colin Seis of ‘Winona’, a farm in the dry central west of NSW, stumbled onto a sustainable farming system that he calls ‘Pasture Cropping’. Using a combination of;
Colin Seis has successfully restored his grasslands. His paddocks now boast over 200 different plant species, which includes a tenfold increase in the original species of native grasses and forbs. Reminder: A forb in botany is a flowering native herb. It excludes grasses, sedges and rushes, as well as woody stemmed plants like shrubs and trees. Charles Massy in his book ‘Call of the Reed Warbler’ describes the dramatic changes at Winona; ‘(There is) evidence of true regeneration with the reappearance of highly palatable but long-lost warm season C4 (native) grasses, which are always the first to disappear under traditional set-stocking. In addition, the (perennial) grass and cropping (system) harbours a huge escalation (125%) in insect biodiversity with 600% greater biomass. This has meant that insect infestation and damage to his crops is now negligible.’ Microbiologist Dr Christine Jones was intrigued by the resurgence of native grasslands at Winona and explained why many species had reappeared; ‘… through his minimum soil disturbance, dramatic reduction in the use of chemicals and fertiliser, he has somehow stimulated mycorrhizal fungi health, getting everything functioning. Getting sugars and all that stuff along the row, which is an ideal situation for plants to germinate in.’ Christine Jones’ suggestion that mycorrhizal fungi have been the catalyst for the return of native plant species is important knowledge in the challenge of restoring grasslands. We know that at least 90% of Australian native plant species have a close symbiotic relationship with mycorrhizal fungi. These fungi support their health, through the absorption of nutrients, and they can be essential for their germination, as is the case for over 400 species of Victorian orchids. Why shouldn’t mycorrhizal fungi also be the catalyst for the germination of many species of grasses and forbs? We can conclude from the work of Colin Seis’ and others that the seed of many native grassland species, as well as the spores of a diverse mix of microorganisms, may be lying dormant in our soils, waiting for the right conditions to regenerate. Recommended reading; ‘Microbes and Plants’ for more insights into the critical role of microbes in our soils. Tea anyone? ... for inoculating soil! A teaspoon of good garden soil, according to microbial geneticists, contains 1 billion bacteria, several yards of fungal hyphae, several thousand protozoa, and a few dozen nematodes. The same quantity of the Biodynamic ‘500’ preparation has an estimated 2.5 billion microbes which include: bacteria, fungi, nematodes and protozoa. (Ehrenfried Pfeiffer 1899-1961) A teaspoon of '500' is stirred into water to produce a dilute microbe-rich tea. This is sprayed onto bare moist soil on a cloudy/rainy day, to avoid direct contact with sunshine, which would kill the microbes. This same practice could be followed with worm, compost and manure teas. Sophie Small, the remarkable Bellarine Landcare facilitator, has been inspired by the writing of Nicole Masters, For the love of Soil. Sophie writes; Turning back the clock - microbial action to regenerate native species. Nicole Masters shares the story of Steve Charter, a rancher from Montana, who grazed his 200 - 400 cows across 8,000 acres of arid land with soils degraded from historical misuse. Steve adopted Allan Savory’s holistic grazing methods in the 1980s to address the degradation of his soils. But it wasn’t until 2014 when he built a custom ‘slurry’ sprayer and mounted it on an old army truck and started applying materials such as liquid composts, molasses, fish, seaweed, rock salt and worm compost across 100's of acres that he started to see dramatic changes to his property. “Through action from the bio-stimulants, the once locally extinct native grasses are returning in droves.” The incidence of bare soil was reduced and the grass “in places is knee-high to waist height”. Steve has treated over 4,000 acres of his property with these products and after many years of trying to recover the health of his land, he finally feels buoyed by the positive changes he’s seen in his soil health and vegetation cover. Nicole Masters also shares an inspiring story from Western Australia. Di and Ian Haggerty, regenerative farmers from WA, purchased a degraded block of cropping land, choked with weeds which seemed impossible to remove. They took action by planting crops accompanied by worm extract, applying compost extract and introducing sheep to graze the land. Two years later three species of native grasses started reappearing and after three years C4 native grasses, genus Setaria, “germinated across thousands of acres. This land had been terribly abused for over 60 years, yet the native seed bank was just waiting for the right signals to germinate.” (Nicole Masters. 2019. For the Love of Soil. Strategies to Regenerate our Food Production Systems, pub. Printable Reality) The Grassy Groundcover Research Project Restoring the diverse families of microbes to the soil appears to be a key catalyst to native grassland recovery, though two major stumbling blocks still need to be overcome;
A system that was specifically designed to overcome these hurdles has consistently succeeded in restoring native grasslands at a number of sites throughout Victoria. John Delpratt, one of the developers of the system, describes its application to restoring roadside vegetation at Woorndoo in two blogs; Kangaroo Grass communities on roadside reserves - Part 1. Kangaroo Grass communities on roadside reserves - Part 2. In these blogs, John also writes about the critical importance of restoring roadside grasslands because of the many aesthetic, practical and environmental benefits they would provide for our nation as a whole. A proven method John Delpratt and Dr Paul Gibson Roy have fine-tuned their method through trials and practice. Here is a brief summary of how it's done;
Growing grassland plants for bulk seed production - how is it done? John Delpratt has offered to describe the process of seed production in a future blog - stay tuned You can also read about this method in the excellent book: ‘Land of sweeping plains – Managing and restoring the native grasslands of south-eastern Australia. Chapters 11 & 12 on grassland restoration by John Delpratt and Paul Gibson-Roy. Though the results of the scalping method are very impressive and the transformation from a weedy grazing paddock to a pure native grassland takes less than twelve months, it requires the coordination of skills and resources that many land managers don’t have available to them. In Part 3 next month you will read about a simpler, though slower method which is more in the spirit of the wisdom of the Taoist philosopher Tao Tzu; ‘Nature doesn’t hurry, yet everything is accomplished.’ Restoring Native Grasslands - Part 3. Look out for the Table of Champions - a list of hardy indigenous grassland plants that have the potential to turn the tables on those unwelcome sneaky exotic weeds. The champion’s list presently includes; 76 species, 50 genera and 22 families from central Victoria. |
Stephen Murphy is an author, an ecologist and a nurseryman. He has been a designer of natural landscapes for over 30 years. He loves the bush, supports Landcare and is a volunteer helping to conserve local reserves. |