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Year 12 Geography
Field Study
“What advantages does No Till farming have over traditional
farming methods in terms of soil health, crop yields and
sustainability?”
Weighting: 30%
SSABSA Registration Number: 875117T
Teacher: Lisa Pope
School: Australian Science and Mathematics School
The purpose of this field study is to investigate the impact no till farming has had on soil
health and crop yields on farms near Port Lincoln, on the Eyre Peninsula. This topic is of
significant importance to me; as my parents own and operate a farm utilizing no till
farming technology.
This field study is based upon the farming practices and past yield results from Peregrine
Hill – A farm 10km north of Port Lincoln on the Lower Eyre Peninsula. It is located at
34° 39.344 S and 135° 49.737 E. Note – On the map below, the farm is labeled “Hadnall
Farm”, following a change of ownership in 1995 it is now named “Peregrine Hill”. .
*Above – Area in red shows Peregrine Hill 34° 39.344 S 135° 49.737 E
No till farming is a system of cropping whereby land is not cultivated prior to seeding in
order to reduce weed growth, instead the stubble from the previous years crop is left in
place and seed directly sowed into the land without prior cultivation. The idea behind this
is to ensure soil health, due to the fact that cultivating land results is moisture losses and
overall degradation of soil.
Peregrine Hill began no till farming in 1998 and was one of the first farms in the local
district to begin the practice. Mark Langford saw the need to reduce erosion to the top
soil by rain and wind. The no till farming practice has enabled the top soil to become
healthier with decomposing organic matter (stubble) from the previous years crop and
higher soil strength levels due to it not being cultivated prior to being seeded.
I aim to investigate this topic through the use of analysis of land, looking at crop yield
results and soil health. I also plan to interview several key people to collect information
about no till farming and the reason it was developed.
Primary sources for information on this topic will include field analysis of soil health,
and past years crop results and information obtained from the Department of Primary
Industries and resources of South Australia regarding weed management, rainfall –
impact of drought and no till farming specifics.
Secondary sources of information for the field study will come from background research
into no till farming practices using information from websites, government agencies and
organizations.
No-Till farming was implemented on Peregrine Hill in order to reduce soil disturbance
which occurs as a result of traditional farming. Typically in traditional farming methods,
land is cultivated prior to the seeding of the year’s crop in order to reduce weed growth.
No-Till farming does not rely on cultivation of the land prior to seeding, but instead relies
on larger spacing between the rows of plants to help with trash (left over stubble from the
year before) clearance and larger, stronger machinery in order to pull through the soil in
one pass rather than many. As a result of this, the top soil does not lose as much moisture
to the environment and the soil will be more likely to stay together during heavy winds,
rather than blow causing dust storms and a value loss of topsoil.
During the cultivation of the land, traditional methods of broad acre cropping will often
result in the loss of top soil due to wind erosion if it is very dry, and rain erosion if it is
very wet. This is due to the soils structure being weakened by the extra cultivation and
the fact that there is often no stubble left to help hold the soil together. Traditional
farming methods often include annually burning the previous years stubble as to allow
machinery to not have clearance issues with the stubble. This is a long term detrimental
effect as the stubble plays a key part in helping to hold the soil together and protect it
from wind and rain.
The increased chemical use inherent by no till farming is a trade off for better soil health
and less reliance on nitrogen based fertilizers. Less pollution is produced during the
cropping process due to machinery only passing over the land once, rather than twice.
Above: Image showing a local farmer working up his land prior to seeding
Above: Soil cross section with the topsoil marked with an “I”.
The following is a soil profile conducted on a properly neighboring Peregrine Hill:
The property this soil profile was conducted on utilizes traditional farming methods. As is
evident, it is lacking in soil nitrates, phosphorus, zinc and copper. This could be due to
many factors, including the method of farming used.
Left: Map showing the
relation of the property the
above soil profile was
conducted, labeled “B”
and in blue. Peregrine Hill
is labeled with “A” and in
red.
The following data table was constructed from data from a soil profile conducted on
Peregrine Hill in 2006.
Test
Result
Nitrate NO3
40mg/kilo
Phosphorus
41mg/kilo
Available Potassium
70mg/kilo
Available Sulfur
7.2mg/kilo
Zinc
0.6mg/kilo
Copper
.43mg/kilo
Manganese
5.2mg/kilo
Chloride
22mb/kilo
Electrical Conductivity (EC)
0.05ds/m
EC of saturated extract (ECe)
0.50ds/m
Organic Carbon
1.9%
In comparing the results of the two soil profiles, the soil profile conducted on Peregrine
Hill better fits the optimal range as indicated on the profile for the neighboring property.
Rainfall has a large impact on soil health as well as the overall success of a crop. No Till
farming helps maintain soil moisture levels, so that in a year with lower than average
rainfall the crop will have the best start possible. Traditionally in periods of drought, dust
storms are often common place. No-Till farming practices help reduce the risk of
potentially devastating dust storms and soil erosion.
In 2005 areas surrounding Port Lincoln and North Shields were affected by bushfire. This
left the soil of paddocks dry due to any moisture in the topsoil being evaporated by the
heat and any remnants of crop stubble, including root systems; burnt, resulting in the soil
being loose and dry. Following the bushfire were several days of severe northerly winds,
resulting in bad dust storms from paddocks that had been burnt. Farms that were
traditionally farmed and no till farmed all suffered as a result of this. The dust storms that
were caused by the strong winds and bushfires were the same as the dust storms that can
be caused by the working up of the land disturbing the top soil. As the bushfire burnt the
stubble of the previous years crop, there was nothing to hold the topsoil together as it was
not moist and the stubble protecting it had been burnt. However, farmers that employed
no-till farming practices noticed that the soil losses due to wind were not as severe
compared to traditionally farmed farms. This was due to the topsoil being slightly
stronger due to it not being disturbed as much in the past.
Above: An image taken from Peregrine Hill showing a grass fire that broke out near
Port Lincoln in Septemper 2006
Traditional farming involves the working up of land prior to seeding to hinder the growth
of weeds. Working up of the land before seeding generally occurs at a time when weeds
have just germinated and are sprouting leaves. The cultivation of the land turns the soil
over, thus burying the foliage, leaving the weed unable to carryout photosynthesis
through its leaves, eventually resulting in its death. Weeds are a problem because they
use nutrients that the crop could be using as well as moisture. If left, some weeds can also
contaminate crops when they are harvested, resulting in the seed needing to be cleaned.
To deal with weed growth, farmers that use the no till farming system will often use
increased amounts of chemicals to control the weed growth. These chemicals have the
potential to pollute the environment. Land water runoff into dams and creeks can
potentially carry with it traces of herbicide which could harm the ecosystems that rely on
these dams and rivers.
In conclusion, it is clear that no till farming is a better alternative to traditional farming.
No Till farming helps reduce the effects of wind and rain erosion by leaving the soil
largely intact, rather than cultivating it prior to seeding. This means that the soil moisture
levels do not suffer as much as traditional farming methods during the working up
process. Because of this and the fact that no till farming does not rely on the burning of
paddocks prior to cultivation, it is a more sustainable practice, especially given the
current drought situation South Australia is in the midst of. Soil nutrient levels on
properties that are no till farmed are also higher, resulting in a lower rate of fertilizer
consumption. The only downside to no till farming is the cost of setting up machinery for
it, as well as increased reliance on herbicide. The cost of machinery is large, which
therefore could make it uneconomical for some farmers to change, given that the cost
could be several times what they may potentially make in that year, especially in the
current drought conditions. The cost of herbicide could also potentially be an issue,
however given that less fertilizer is used, this is largely offset. The environmental impacts
of herbicide once again could be considered an issue, however these can be offset due to
lower pollution levels produced when the crop was sown given that the paddocks did not
require burning nor cultivation prior to seeding.