Recreating the Country blog |
Dear reader, this blog is divided into two parts which can be read separately:
A modern Landcare fable In 1989 Prime Minister Bob Hawke was on his way to launch ‘a decade of Landcare’ in country Victoria. As he was being driven down a quiet country lane, he spotted an old woman in the middle of a paddock planting a tree. He lent forward and asked his driver to stop the car, “give me a minute can you Bill?” Bill couldn’t believe his eyes as he watched the Prime Minster of Australia climb the wire fence in his pressed suit and polished shoes. He walked across the grassy paddock toward the old woman with a string of confused reporters in tow. He called back to the reporters, “Ahhh, could you people give us a bit of privacy” From a distance, the huddle of reporters could just make out the conversation; “Gooday darlen”, said Hawke, “looks like you could do with some help”. He put out is hand and said “Bob’s my name”. The old women looked up with a curious smile. “Pleased to meet you Bob, Una’s my name. I can see you’re dressed for the occasion Bob”. She handed him the shovel and said’ “I suppose you know what this is for?” Bob gave her a big pearly grin and took the shovel. “Where do you want the hole Una?” As he pushed the shovel into the soil he said, “Una, do you mind if I ask your age”? Una, “I’m 87 today”. She paused as she considered, “I’ve planted a River Red Gum on my birthday since I had my first baby nearly seventy years ago”. “I’m impressed Una” said Bob. “Then why aren’t your children and grandchildren out here helping”? “They’re busy planting a thousand trees in the next paddock along the creek”, Una said. “Though, this is something I like to do myself, while I think about the year that’s just passed. She then said with conviction, “I think planting a tree is the best thing a person can do for the land and for the environment” Bob thought for a moment and said, “You’re an inspiring woman Una and I can see you have a lot more years left in you, but I doubt you’ll ever see your grandchildren climb the tree you’re planting today” Una, “Bob don’t you know the old Greek proverb”. Bob, “Can’t say that I do”. Una stood tall and looked directly at Bob, "A society grows great when old men plant trees in whose shade they know they shall never sit". And I could add Bob” said Una with a gentle smile, “a society grows even greater when both men and women plant trees that they will never see mature”. Bob considered for a moment and said mischievously, “Have you got another tree in that bucket Una? I think we’d better plant two”. The fable ends here but Una's story continues at the end of the blog... and it has a twist that you might not see coming. The benefits of Paddock trees: Benefits to stock and crops
After the study John came up with a radical 100 year plan that would enable him to plant paddock trees on the rest of his farm. The plan would also allow the existing old trees to regenerate naturally. You can read about how John did this in 'Paddock Trees part 3 - how to protect, regenerate & replant' Entomologist Dr Ian Smith from Ecologian supported John's findings at a recent Landcare presentation. He confirmed that scattered paddock trees provide better general wind shelter than shelter-belt plantations. This is because there is no turbulence or increase in wind velocities downwind beyond the protection zone of tree belts. On windy days paddock trees provide a more even and less turbulent reduction in wind throughout a protected paddock. Shelter belts planted across a farm at regular intervals of 100 - 200 meters, combined with scattered paddocks trees between the shelter belts, will provide the most wind protection in paddocks for stock and crops.
Studies show that sheep produce more wool and cows increase milk production by up to 20% in sheltered paddocks. New lambs are more likely to thrive in environments protected from the wind with 20% less mortality.
How wind dehydrates plants? Plants maintain humidity over the surface of their leaves through their stomata. Strong winds remove this moist layer, drying the leaf surface. Plants try to replace this lost moisture, which the winds remove again, creating a leaf drying cycle. This dehydrates plants putting them under stress, usually causing them to wilt
Paddock trees create a cooler micro-climate and can reduce the radiant heat on hot days by more than 50%. This shade also benefits the farmers working around their property. http://coolcows.dairyaustralia.com.au/infrastructure/trees-for-shade Benefits to the land
Soil on farms is a precious commodity that forms at an estimated rate of 10mm/1000 years in Australia’s southern states. It makes sense to protect this valuable asset, yet we lose tonnes each year through wind and water erosion. It’s estimated that the world loses more than 24 billion tonnes of fertile soil to erosion every year. In Australia dust storms carrying soil have become more common in dry years. Older Australians will remember February 8th 1983 when ‘the Mallee came to Melbourne’ and an estimated 140 million kg of topsoil was carried away in a dust storm that threw Melbourne into total darkness in the middle of the day. I recall a visit to a farm in Deans Marsh, Victoria in the mid 1980’s. The owner told the story of how his grandfather cleared a paddock of trees and shrubs for cropping. He then scalped a line through the paddock to create a shallow drain. Two generations later this shallow drain had become deep and wide enough to hide a two story house. Tonnes of precious soil had been washed down the Yan Yan Gurt Creek into Bass Strait. To prevent further soil loss the grandson was replanting trees and shrubs on the Creek and throughout the farm. Maintaining paddock trees, allowing the old trees to regenerate and planting scattered trees in bare paddocks is a strategy that would help address this significant and damaging annual loss of soil
Paddock trees have deep roots that search the subsoil and the deeper bedrock for minerals. Through osmosis and ion exchange mechanisms they absorb these minerals concentrating them in their leaves. These minerals are added to the soil around the tree when the leaves fall and decompose. Carbon from this leaf litter is also incorporated into the soil by insects like Springtails, (Class Collembola). These little insects are often seen in your garden leaping about when a log/rock is lifted uncovering their home. They are specialists in breaking down hard woody material into soil enriching and moisture holding humus. Soil fertility is also enriched by birds, marsupials and insects living in paddock trees. The nutrient rich animal droppings are vital to the health and survival of these isolated trees because they often grow in poorer soils low in nitrogen and phosphorus. Use this link to read more about paddock trees and birds and how they have built a mutually beneficial relationship
Salt (sodium chloride or table salt) rising from the water table to the surface is called ‘dryland salinity’ and kills most plants. Farms with severe dryland salinity can look like deserts. Also high levels of sodium in soil changes its structure making it very erodible. Deep gullies can develop overnight after heavy rain. Dryland salinity devastated many farms in the 1980’s and 1990’s and became a focus for Landcare in its early years. Dryland salinity explainer Big trees are nature’s water pumps, taking most of their water deep down at the water table. One mature tree can drink 500 – 1000 L of water/day & in one day 1000 mature trees could empty an Olympic sized swimming pool. When millions of big trees are removed from the landscape, pumping from water-tables stops and the ‘Olympic pools’ deep underground (called groundwater) overflow and the water level rises to the surface. Often this water is naturally quite salty and it's made saltier at the surface by evaporation. These high levels of salt brought to the soil surface cause dryland salinity and are toxic to most plants. The simple solution to dryland salinity is trees. Keeping existing paddock trees healthy, allowing them to regenerate. Planting trees back onto the broader landscape is also an accepted strategy that will start to reverse dryland salinity in as little as five years. To read more about dryland salinity click here for a CSIRO article 'Dealing with Dryland Salinity' How biodiversity benefits farm production
Compared to areas without trees, even a small increase in numbers to 5 trees/ha in an agricultural landscape significantly increases the numbers of bats and birds present. The presence of a single tree can double the number of bird species. Paddock trees are also stepping-stones for animal movement between patches of native bush making it possible for wildlife to access the diversity of foods and habitats that they need to 'make a living'.
Interestingly studies show that one x 100 year old tree produces a lot more nectar and pollen than two x 50 year old trees. So the food produced by old trees increases significantly as they mature supporting more wildlife and providing proportionally more pest control benefits. Increase bird and micro-bat numbers reduces pest insect species. Owls live in tree hollows and eat mice and rats, insectivorous birds like the Pardalote, Welcome Swallow and honey-eaters fly kilometres from their home trees searching for insects. Many of these are pests that damage grain crops as well as trees producing fruit and nuts. Magpies perched on old paddock trees have been recorded feeding on snails and slugs in vineyards. They also scare grape-eating birds like Starlings and Blackbirds reducing damage to bunches Ecologist Dr Rebecca Peisley from Charles Sturt University found that insect damage to apple orchards, vineyards and crops was reduced when sites were close to native vegetation. She also found raptors that control rabbits preferred paddocks with large paddock trees. Micro bats that live in hollows and fissures in paddock trees can consume 500 insects in an hour and half their body weight in insects every night. They also make a significant dint in mosquito populations. Parasitic wasps are attracted to paddock trees to feed on nectar and pollen. They lay their eggs on leaf-eating caterpillars keeping their numbers in check. They are critical to maintaining the insect balance on urban and rural landscapes. More benefits
Hugging a tree also improves our wellbeing. Click and scroll to the end to read about 'the science of tree hugging'
They are also a convenient source of firewood and craft wood that would be valued on farms. A practice of take one & leave one is the policy that we adopted on our rural property. This provides for both personal needs and the needs of wildlife.
Because older trees produce consistently more nectar and pollen, honey products from paddock trees could be a valuable supplement to a farm income and the farm pantry. Feral bees will evict native fauna from tree hollows but well managed hives would pose little or no threat to native fauna. Video on paddock trees The Fenner School of Environment and Society at the Australian National University has posted this 9.5 minute earthy video on the values of Scattered Trees on farms. Click here to watch. ....Una's story continues here; A parallel universe – imagine the perfect world Una watched the reporters trailing behind as Bob walked briskly toward his waiting car. She smiled as she thought of the geese in her orchard honking excitedly at feeding time. The animated gaggle of reporters talked amongst themselves, occasionally looking back to Una and nodding their heads in her direction as a sign of respect. Una chuckled, she was well aware of who Bob was but she hadn’t let on. She decided that she liked him and his ambitious plan to plant one billion trees. Her son Malcolm wouldn’t believe her story, or maybe he would when he saw the newspaper headlines the next day.
Paddock Trees - part 3. 'Restoring paddock trees and fostering the next generation' . Explores how we can protect paddock trees and restore them on our rural landscapes Paddock Trees - part 1. 'Their beauty and their bounty'. Explores the amazing benefits to the environment that old paddock trees provide.
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John Delpratt John is an Honorary Fellow with the University of Melbourne. He was a lecturer in plant production and seed technology at the University’s Burnley campus for 25 years prior to his retirement. His involvement with native grassland conservation focused initially on cultivation and seed production systems for grassland forbs and later on the reconstruction and management of diverse native grassland communities for both ecological and horticultural applications. Over the past few months, Steve has introduced the native grasslands and grassy woodlands of temperate Australia; what we know of their management and why we are losing the battle to save them – a compelling story in four Blogs. I have the privilege of adding my own contribution to this discussion. The critical element for any conservation activity is HOPE Constantly, we are reminded that natural temperate grasslands and grassy woodlands are among Australia’s most endangered plant communities. We watch in disbelief and frustration as these complex and beautiful communities are incrementally degraded, reduced and obliterated by human activities such as urban expansion, pasture modification and cropping, and road and roadside operations. Historically kangaroo grazing was important for the health of grasslands Grazing is a natural process in the life of a grassland or grassy woodland. Before British settlement mobs of kangaroos would randomly move about their home range and graze on the most succulent grasses and herbs. This chance grazing pattern created patchworks of long and short grass providing different habitats for wildlife. Where the grass was longer in a eucalypt woodland, the nocturnal Rufous Bettong would prosper. In the shorter grassed areas, many of the ground feeding parrot species could feed. Chance grazing was an important part of the grassland ecology and it provided habitats that supported hundreds of native insects and animals and the ecological services they provided. Today there are more kangaroos and fewer grasslands In the twenty-first century kangaroos are still important grazers in our parks and reserves, but two things have changed. There are now more kangaroos and less grasslands for them to graze. These grasslands are also in isolated pockets, forcing kangaroos to spill over onto private land. This allows the mobs to grow well beyond the capacity of the native grassland to support them, putting more pressure on the grassland plants often with disastrous results. This artificial ‘static’ grazing pattern is a radical change from the natural pattern of grazing mobs constantly on the move. A moving mob grazes more generally and doesn’t have time to target the tasty plants. Static grazing allows animals to pick and choose resulting in tasty plants being constantly overgrazed and potentially vanishing. Grazing is a species balancer Grazing also helps to ‘open up’ the grasslands. For example when a dominant native grass like Kangaroo Grass, Themeda triandra, is not grazed or burnt for more than ten years, it can become too crowded, choking-out neighbouring herbs and orchids. The Kangaroo Grass eventually declines because of a build-up of dead grass at its base. In contrast, if Kangaroo Grass is grazed or burnt regularly, there are inter-tussock spaces or gaps for other plants to occupy. The Kangaroo Grass is also healthier, each plant potentially living for more than 100 years. The overall result is a stable and diverse grassland plant and animal community. Grazing can control introduced grasses Aggressive introduced grasses that displace native species in grasslands are difficult to control. Hand weeding is a useful method for small areas but it is labour intensive and creates soil disturbance that encourages more weeds to grow. Spraying with herbicides is expensive, has associated health risks and there are only a few selective chemicals like flupropanate that target problem weeds like Serrated Tussock or Chilean Needle-grass that may be growing in a pristine grassland. Grazing is little used to maintain the health and diversity of grasslands but it has the potential to be a very useful tool. Associate Professor Ian Lunt commented on grazing in The Conversation in 2012; ‘In Tasmania, a number of threatened native plant species survive in grazed areas; if stock are removed the plants are smothered by thick grasses and decline’. Click on this link to read Ian Lunt's complete article; theconversation.com/can-livestock-grazing-benefit-biodiversity-10789 In Chinamans Lagoon, an 8ha reserve within the township of Teesdale, Victoria, the removal of grazing animals had a profound effect. Two horses and a few sheep had grazed in the reserve for decades suppressing Veldt grasses enough for 55 species of indigenous plants to flourish. In 2002 the grazing animals were removed and this enabled two species of South African Veldt grass, Perrenial, Ehrharta Calycina; and Annual, E. longiflora to spread, eventually swamping the native grassland species within ten years. In 2017 only 8 tree & shrub species and 5 grass species could be found. To read more about identifying and controlling veldt grasses click here; Merinos to the rescue In 2016 the wet spring produced exceptional veldt grass growth in Chinamans Lagoon which was a significant fire risk to the Teesdale community. Mowing or brush cutting the long grass wasn’t practical because of the native trees and the ground debris. Research suggested that heavy grazing is the Achilles-heal of Veldt grasses so in September 80 Merino sheep (10 sheep/ha) were introduced over four weeks. This trial was hoping to stress the invading veldt grasses and also open up more inter-tussock spaces for the indigenous grasses to recolonise. The Merinos did an excellent job of reducing the fire risk and preferred eating the exotic veldt grasses and avoided the native spear grasses and wallaby grasses for the first two weeks. The long term plan is to graze the lagoon annually in early spring to weaken the hold of the veldt grasses to allow the native flora to recover. Ian Lunt in another grazing study observed that it took three years for the benefits of grazing became apparent. ianluntecology.com/2011/11/08/restoring-woodland-understories-4/. Pulse grazing to restore grasslands The ecology of a grassland benefits most from a large mob of kangaroos grazing randomly and then moving on. Pulse grazing with a mob of sheep mimics this pattern of grazing and potentially can be used as a grassland restoration tool. Sheep left to graze for long periods create an even heavily grazed grassy landscape. This may look attractive, but for wildlife it spells loss of habitat and for the grassland it spells loss of biodiversity. Pulse grazing produces an uneven landscape. To achieve this effect a large number of stock are introduced for a very short time. Also called crash/patch/mob grazing, the short grazing time avoids ‘tasty’ plants being targeted and results in more general grazing. In essence the mob is slowly walked through the grassland nibbling as they walk like the kangaroo mobs of old. The number of sheep needed to mimic a mob of kangaroos is likely to be very high. The flock sizes will be much higher than recommended stocking rates. Normally a native grassland would support 1 – 2 sheep/ha if the sheep are left to graze in a paddock for months. Pulse grazing stocking rates over 1 – 2 days, are likely to be 10 – 20 times higher than the recommended rates. For example a 20 ha reserve may require a flock of 200 - 400 sheep. Dividing the grassland into small areas with portable electric fencing would enable flocks to be moved daily, producing a desirable patchwork landscape. This would be quite time consuming, but the grazing process would only need to be repeated every 1 – 5 years to keep the grassland healthy. A less time consuming alternative could be found by experimenting with smaller flocks in larger patches over 1 – 2 weeks. To find the right formula some monitoring of the grassland would be necessary. The sheep would be moved when prominent, easy to observe indicator plants were starting to be heavily grazed. Whatever strategy of pulse grazing is adopted, deciding on some management goals like increased species diversity and reduced dominance of certain native grasses is important. Set up photopoints at marked fence posts and in patches containing key species, marked with a hardwood peg, for a valuable aid to recognise change. The plan is to come back each year to the same locations at a similar time and point the camera in the same direction to get the same photo. Comparing the photos over time is a wonderful reminder of where you started and how much the landscape has changed. Below is a set of photopoints that I took in the Teesdale Grassy Woodlands Reserve to monitor Gorse, Ulex europaeus control. Hover over the images for an explanation. Pulse grazing is working miracles in Africa Ecologist Allan Savory, who is reversing desertification in 15,000,000ha on five continents, promotes ‘Holistic Management and Planned Grazing’ which is very similar to pulse grazing. Savory advocates using huge flocks of sheep or huge herds of cattle. With his grazing system he is turning bare deserts into lush grasslands, but the critical ingredient is that he mimics the constant movement of the wild herds of Wildebeest grazing on the savannahs of Africa. See his TED presentation below, already viewed 4.5 million people, to be inspired with his simple solution to climate change; www.ted.com/talks/allan_savory_how_to_green_the_world_s_deserts_and_reverse_climate_change Pulse grazing - something to chew on Pulse grazing with large flocks of Merinos mimics the historic grazing pattern of mobs of kangaroos. This should benefit grassland ecologies if it is done when the soil is firm, to avoid compaction caused by hard hooves. Flowering and seed set times will be less important for pulse grazing as many plants will be undamaged in this short grazing cycle. For longer periods of grazing of 1 – 2+ weeks, monitoring grazing will be an important trigger for sheep removal. Flowering and seed set times in spring are times when the sheep should be removed to allow plants to complete their reproductive cycle. To read more on monitoring grazing in native grasslands for conservation click here In Part 5 of the Grassland series guest blogger and respected grassland expert John Delpratt will consider the future of Kangaroo Grasslands in roadside reserves. How they are faring and how we can best look after or restore them To be posted in April |
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. |