Grazing and animal impact
(We apologise that no photos are yet available to illustrate the points made here - we hope to have some soon!
The major point those making laws should realise is that to manage plants and soil so that it can improve requires flexibility, timing, and intensity of stock numbers. Laws tend to do the reverse - inflexibility, unable to make decisions quickly, and restricting decision making options )
Grazing
Running stock on the land is assumed to be a simple process." Everyone" knows that graziers keep livestock on their properties to make a living but not everyone knows that these animals can also be used as tools to effect the land they live on.
Large grazing animals do three main things that effect the ecosystem that they are a part of.
They graze, they deposit dung and urine and they trample plants and the soil. These things can be used to help or harm.
Livestock can kill plants, compact and erode soil and destroy habitat of native animals
or
they can be used to keep plants fresh, healthy and diverse, keep the soil open and covered with litter, heal erosion and create conditions suitable for native fauna.
These good or bad results can happen quickly or slowly. The "good" and "bad" results can even be found co-existing in the same paddock! Some plants in a paddock may be over-grazed to death while others are kept healthy by appropriate grazing and others are dying from being rested too long. The same paddock may have cattle tracks beginning to erode in one place while nearby the hooves of excited cattle have broken up capped bare ground and trampled down grass to make litter to cover the loose soil - making an ideal seed bed and an improved water cycle.
It all has to do with timing and to manage that timing requires knowledge, money and determination.
Firstly it helps to understand some basic things about plants.
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Stage 1: The plant has been freshly grazed and is beginning to reshoot, drawing on energy from it's roots.
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Stage 2: The plant is half grown and has enough green leaf to be capturing enough light for it's future growth with-out drawing on root reserves.
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Stage 3: The plant has recovered from being grazed and is storing energy in it's roots.
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Over-grazing
If a plant is grazed during the first stage, it is forced to use more energy from it`s roots to begin growing again. Should a plant be continually grazed during stage one, then it recovers more and more slowly and may die. If a plant is grazed during stage two it will not harm the plant so long as the grazing does not remove so much leaf that the plant is set back to stage one again. Since it is hard to know whether or not livestock will graze a plant too low (called severe grazing) it is safer not to let livestock graze pastures that are still in stage two.
Overgrazing happens when a plant is forced to keep drawing on energy from it's roots over and over with-out a chance to recover and some plants grow horizontally (staying close to the ground to avoid animal mouths) rather than vertically. This gives a degree of protection as a result.
It is only in stage three that energy is replenished in the roots of the plant (due to photosynthesis in the leaves).
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Stage 4: The soil moisture is low. The plant has dried out and become dormant having stored energy in it's roots ready to regrow with the next rains
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Stage 5: Opening rains have come, the plant is in stage one again and is drawing on stored energy to regrow. It is hampered by the old growth that is shading the growth points near the base.
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Appropriate Grazing
When a plant reaches stage three it has finished replenishing the energy in it's roots and has finished most of it's growing and can cope with being eaten again. If the season dries out before a plant has time to recover and the plant dries out completely so that it will have to reshoot again from the base when rains come, then it can be eaten or trampled by stock while it is dormant with-out any more harm than would have come to it anyway.
Over-resting
If a plant is left with-out being grazed, trampled or burnt for several growing seasons the old dead leaves shade the plants growth points and the plant can eventually die.
This is more of a problem in areas with erratic rainfall and low humidity where plant material above ground does not easily rot (arid zone). In areas where dead things rot easily (humid areas) the old leaves on the plant would go green and slimy and fall to the ground with-out being grazed, leaving the plant's growth points free of old growth. These high humidity areas are where you find rainforest type environments. Most of Australia's range lands lie at the other end of the scale. In these extensive grazing areas, old grass leaves stay upright turning yellow, then white, then grey. Even dead animals sometimes mummify rather than decompose!
These non-humid environments have been referred to as "brittle" environments and it is not uncommon to see bushy old grass plants growing in circles, because their centres, which experienced the most shading, have died and left only the outside ring of leaves alive and bare soil in the centre.
Some plants cope better with over-resting because their growth points are not at the base of the plant but rather all along the stem. One common grass like this is Buffel which is a very common introduced grass in Queensland. It has been called a weed by some environmental groups because it often out competes native grasses. Buffel copes well with both over-grazing and over-resting but when grazing is managed so that most of the grazing occurs in stage three then Buffel is less likely to form a monoculture and native grasses have a better chance.
Timing
A grazier who understands these principals will try to time the grazing of his pastures so that livestock are not left on grazed areas long enough to regraze plants that are just beginning to reshoot. He will also try not to move his stock onto pasture that was previously grazed but has not yet completely recovered to stage three. At the same time he will try to make sure that all the plants in his pasture are grazed at least once a year. As you can imagine this is a complex undertaking.
As well as considering grazing, the trampling of stock hooves on the ground is beneficial when the land is given plenty of time to recover. Imagine a group of 100 cows in a 1000 acre paddock all year round.They will have favourite places to lay and walk which will soon become bare and at risk of erosion. Now imagine 100 cows in a 2.7 acre paddock for a day. Anything they don`t eat, they will trample down. Any bare areas will be scratched and broken up and covered in urine and manure by the time they leave the paddock. If there are 370 of these paddocks, each one will have more than a year to recover.
Both groups of cows in this example are being run at a rate of 1 cow to 10 acres. The stocking rate over a year is the same but the effect on the land is vastly different.
The theory is easy, but setting up the management is the challenge, especially if you already have a large debt.
There are several methods landholders are using to attempt to get the best grazing and animal impact results possible within the constraints of their finances. These may have names like cell grazing, time control grazing, holistic or planned grazing, or pulse grazing. Because it usually takes a lot of money to put in lots of watering points and new fences, the uptake of this grazing approach is gradual.
If landholders can get a good handle on this management the results are impressive.
Some landholders results
Bob McFarland "Oxley" Hay NSW
Since 96-97, Bob has been using a moderately intensive planned grazing arrangement on land that had been severely grazed by sheep since the 1840`s. The rest period is usually from 240 to 300 days, running 6,400 grown sheep plus lambs plus 150 cattle over an area of 24,000 acres.
The results are an increase in palatable native grasses including saltbush and kangaroo grass, and a lessening of weeds such as bassias, glass swartz and unpaltable forbs.
Stock health has improved, weaners don`t lose condition which happened previously and stocking rate has improved approximately 20%
Bob would like to get more intensity but watering points are his limiting factor.
He has used animal impact to reclaim a scalded area of 4.2ha using 183 cattle which were kept just on that area and fed hay for 6 weeks.
Richard Makim "Arizona" Julia Creek, Qld
Richard has been gradually adding fences and waters for a couple of years to get more intensity and greater rest periods on his 64,000 ha property. With just 35 paddocks and 5 groups of cattle ,he is already getting good results. Several native grasses including bluegrass have come back and new plants are everywhere.
Richard wants to get a lot more intensity as funds become available.
Artie Lord "Sutherland" Richmond Qld
Artie began to make changes in 1994 on his 29,700ha desert property. He now has 87 paddocks and is getting very good results. There is a great variety of plants including stylos and legumes as well as a lot of native grasses and buffel. Almost all the bare areas have disapeared and organic matter on the soil surface has increased substantially. The stock numbers have increased from 250 head to 900 head of breeding cattle.
On some downs country he is getting trees with edible leaves to estabish naturally, because he is managing the rest period for that goal.
His management is good enough to be able to know his what his grass reserves are 6 months ahead and either lighten off or whatever well before the district markets are affected when coming into a dry period. This also gives him the opportunity to maybe grab a bargain later if he has lightened off too much.
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