AGRONOMY MATTERS
AGRONOMY Volume 6, Issue 1
MATTERS
Summer edition 2009 - Trials supplement
Pastures profits and broomrape trial 2008 - summary The medic pastures were much less productive than cereals and grasses. There were a number of reasons for this. Establishment was poor, resulting in suboptimum medic density and increased weed competition. Due to the high cost of seed it is not economic to establish plants at high densities. In the first establishment year, seed production for the future should be considered a greater priority than dry matter production.
KEY MESSAGES • Grazed cereals most profitable and aids broomrape control.
• Stocking rates need to be increased to utilise additional feed.
• Medic pastures are a long term investment. • Spray graze unreliable for broomrape control. • Ettrick best all-round performers. The trial consisted of 5 different plots, which were managed by different farmer groups, competing for the most profitable pasture system. Seed, fertiliser and herbicide inputs were varied in an effort to produce the most pasture of highest quality for the lowest cost. For further detail on the trial outline please refer to previous editions of Agronomy Matters. From table 1 it can be seen that the grazed cereals
The theoretical annual stocking rates in table 1 give an indication of the potential for improved pastures to run higher stocking rates. The assumed 100% utilisation and hence 10 DSE on grazed oats and barley may not be achievable. Although with similar utilisations, three times the stocking rate is possible on a grazed cereal when compared to district practice. The additional production and costs per ha associated with grazed cereals are not worthwhile if the extra feed is not used. When grazing more productive pastures, higher stocking rates are needed to turn the additional feed into saleable product. If capital is not available for stock purchase, increasing area used for grain production can increase stocking rates.
Table 1 - production comparisons
Total DM(kg/ha)
Average green feed ME (MJ/kg DM)
Average Crude Protein %
Theoretical Annual DSE/ha average^
Group
Crop
Younghusband
Oats and medic
1902
13.1
18.95
10.1
Ettrick
Cereal rye
1650
12.65
28.3
8.4
Elders/Mypolonga Traders Ryegrass
1776
12.15
15.6
8.6
District practice
Toreador medic
756
11.1
22
3.3
Rural Solutions SA
Angel medic
324
11.4
23.5
1.4
^assuming 7MJME/DSE/day, 100% pasture utilisation, but typically 30-70% (Younghusband and Ettrick) were good performers, producing large amounts of high quality feed. Other trials across the Mallee reinforced the ability of cereals to produce plentiful feed. The Winter Star ryegrass on Elders/ Mypolonga Traders plot was also very productive. Cereal and grass pastures also have the benefit of a wide range of broomrape control options for level 4 paddocks.
It can be seen that the protein content of cereals is high. Young growing stock have the highest requirement for protein, needing 15%. Additional protein is excreted from the animal as waste. Hence the higher protein content of cereals provides no advantage over the protein content of ryegrass and medic pastures. From table 2 it can be seen (Continued on page 2)
Volume 6, Issue 1
Page 2
major sponsors: Hi-fert and Elders.
(Continued from page 1)
that the cost of fodder production ranged from just under $100 to almost $500 per tonne. The lower this cost the better as it means stock can be fed for less. Economically medics were poor performers. However this can be misleading, as it is the year of establishment. The medic pastures have the potential to recuperate some of this years loss over the next few years as production will increase and
We would also like to thank the participating groups: Elders/Mypolonga Traders, Ettrick and Younghusband. During 2009 our attention will be focused on some grazing cereals trials in the Younghusband/Ettrick area, a project funded by National Landcare Program sustainable practices grant. There will also be a pasture trial at the
Table 2 - economic comparisons
Input costs/ha
Cost/tonne DM
Gross income/ha*
Gross margin/ha
Younghusband
$177
$93
$304
$127
Ettrick
$145
$88
$252
$107
Elders/Mypolonga Traders
$208
$117
$259
$50
District practice
$112
$148
$99
-$14
Rural Solutions SA
$149
$460
$43
-$106
Group
*Assuming gross income of $30 per DSE Table 3 - weed control
Broadleaf control herbicide
Broad leaf weeds/m2*
700ml MCPA 500 (Spray graze)
34
3.5g Ally
1
1000ml MCPA 500 (Spray graze)
6
District practice
25g Broadstrike
6
Rural Solutions SA
25g Broadstrike
13
Group Younghusband Ettrick Elders/Mypolonga Traders
* counts taken on 26/09/08, time of potential BBr emergence input costs will be limited to fertiliser. Elders/Mypolonga Traders had the highest input and no relative increase in production. This demonstrated that production is rainfall limited and hence there is an optimum input cost, which produces feed for the least cost per tonne. Ettrick and Younghusband groups were closest to this as they had the lowest costs of production per tonne.
new Brinkley site on Michael Willis’s property. The trial will look at the effect of herbicide type and timing of application on broadleaf weed control in a variety of pasture systems. AM
From table 3 above it can be seen that Younghusband had a high density of broadleaf weeds. The plot was sprayed with 700ml of MCPA 500 on 26th August. This demonstrated the ineffectiveness of a spray graze late in the season. Possible explanations could have been too lage weeds or insufficient stocking rate. Although Younghusband were the most productive and had the highest gross margin, they also had a high risk of broomrape emergence. Ettrick was the best performing group for 2008 as they had a high gross margin as well as good broomrape control. Keith Bolto and Craig Bell would like to thank Phil Dabinett for his time, land and stock. We would also like to thank the
Ettrick’s weed free cereal rye
Volume 6, Issue 1
Page 3
Sustainable and productive pasture systems in the Murray Mallee Final Report summary KEY MESSAGES
Location 1
• Rye, wheat and barley are cereal pasture
Waikerie
options for the feed gap in the Mallee.
• All cereals can be grazed up to the early tillering stage with little grain penalty in the Mallee.
• Cereals provide high quality and quantity feed.
Growing season Rainfall: 140.8 mm Soil Type: Loamy Sand Paddock History: Unsown for last few years
Why grazing cereals? Grazing cereals is not a new technique in mixed farming enterprises, but after intensive cropping took hold it has been used less and less.
Location 2
In low rainfall regions such as the Mallee, grazing cereals seems to be working very well compared to other pasture systems that are not really reliable during feed shortage months (March-July).
Soil Type: Loamy Sand
There is a debate between feeding livestock with A) grain and hay or B) sown cereals for grazing, during feed shortage months. A sown cereal as pasture is a higher input option, but the amount of feed and liveweight gain are significantly higher. Another bonus of grazing cereals is if the season turns out favourably with adequate rainfall, then farmers can get grain yield out of the paddock too.
2006: Pasture
Apart from providing bulk feed for livestock during feed shortage months of the year, early-sown cereals for feed will maintain good ground cover and enhance storage of rainfall in the soil profile. This stored moisture will be used by crops more efficiently as we get closer to the end of the cropping season and will contribute directly to grain yield. Successful farmers’ strategy is to treat their paddock as a crop paddock and graze it rotationally up until early to midtillering, then shut the gate on livestock. If the paddock receives a reasonable rain during July, then there would be a good opportunity for grain harvest, otherwise there always is the option of cutting it for hay. Another successful strategy implemented by South Australian Mallee farmers (especially those who wanted to be on a safer side) is to sow the paddock early merely for feed, and in favourable seasons when they have enough feed on offer in other paddocks they remove livestock from the grazed cereal paddock (before late tillering stage) and turn it into potential grain. In selecting pasture for your farming system there are a few points that need to be taken into consideration, such as
Mannum Growing season Rainfall: 133.6 mm
Paddock History: 2007: Wheat
Location 2
Wynarka Growing season Rainfall: 235 mm Soil Type: Loamy Sand Paddock History: 2007: Wheat 2006: Vetch
when and how much feed you will be needing, quality of feed and possible animal health issues, weed competition and broadleaved weed control (especially host broadleaves in Branched Broomrape quarantine area), fitting into farm rotation to provide early autumn feed and a root disease break for future cropping. In all Murray Mallee research/demonstration sites results proved that all cereals can be comfortably grazed up to their start of tillering (GS 26) without any yield penalty. There has been some difference in yield between grazed and ungrazed areas after their growing stage 28 (late tillering), where in some cereals such as barley, wheat (Continued on page 4)
Volume 6, Issue 1
Page 4
(Continued from page 3)
and rye weren’t as significant and dramatic as triticale and oats. The main tiller in triticale carries the majority of grain and if it gets grazed or damaged by hard grazing, yield will be affected drastically. The same scenario applies to oats varieties and recovery from grazing wasn’t as great as other cereals. Also in grazing oats we have to be careful about weed management strategies as oats is not a good competitor for barley grass, silver grass and brome grass. These weeds can easily take over oats if its growth is set back by grazing. How was the trial done? We had three different sites in Waikerie, Mannum and Wynarka. Diverse varieties of cereals (Barque, Flagship and Maritime barley, Yitpi and Wyalkatchem wheat, Wintaroo
a decision making tool. Rhizoctonia dramatically affected barley varieties, while other cereals (especially rye and triticale) handled Rhizoctonia much better. Total rainfall during the growing season was 140.8 mm which was below average season (Decile 4), combined with June/July moisture and frost stress made a perfect season for failure! Out of all varieties at Waikerie site, rye and wheat performed the best feed-wise and gross income-wise, then came triticale and barley. Under performance of barley was thought to be due to root disease and weed competition later on. The worst was oats that couldn’t compete with weeds after June/July moisture stress.
Grain, Dry Matter, and Gross Margin comparison of grazing cereals- Waikerie 2008 1000
120
Figure 1
100
kg/ha Dm&Grain
800 700
80
600 500
60
400 40
300 200
Gross Margin/ha
900
20
100
and Wallaroo oats, Rufus, Speedy and Tahara triticale, Bevy rye and canola), with various seeding rates (district practice and higher rates) and fertiliser rates tested in Waikerie and Mannum, whilst the main focus of the Wynarka site were on medic and annual ryegrass optimum productivity and seeding rates (Angel and Jaguar medic, Tetrone ryegrass). All sites were sown early and dry (Waikerie on 11th April, Mannum on 3rd May and Wynarka on 15th April). Seeding method was an airseeder with 9” and 12” spacing. Fertiliser rates were 50 and 100 kg/ha DAP at Waikerie, 40 kg/ha DAP at Mannum and 40, 80, 120 kg/ha DAP at the Wynarka site. Grazing method at Wynarka and Mannum were grazing by sheep, whilst at Waikerie site we simulated grazing by mowing the trial to 5 cm height at specific growing stages. What happened? At Waikerie: High level of Rhizoctonia and other root disease at Waikerie trial site reinforced the necessity of soil root disease test as
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Sp
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Tr it i
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Tr itic
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Ru fu s
Ba rle y
Ba r ly e
M
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0
Ba rle y
0
DM Grain GM
Higher seeding and fertiliser rates didn’t perform as expected and there was not a significant difference between district practice and higher rates, which could be due to low level of moisture in the soil at the Waikerie trial site. Out of all dual purpose cereals, wheat varieties showed the best gross income at the Waikerie trial site (2008). Although wheat did not produced the highest amount of feed compared to other grazing cereals, distribution of feed supply during the season was more even (leaning to late feed supply) due to wheat’s winter growing season. Yitpi and Wyalkatchem wheat both showed the same pattern of feed supply, grain yield and close gross income (Figure 1). Cereal rye appears to be a viable option for Murray Mallee hilly and lighter soil paddocks, due to its vigorous growth. Majority of Mallee farmers tend to sow cereal rye merely for grazing, but those farmers who treated their cereal rye paddock as a crop paddock have been harvesting reasonable grain. Their strategy was to keep an eye open for opening rainfall forecast and sow the paddock just before or after that. In a few instances there were farmers who treated their grazing rye as crop, stopped grazing it (Continued on page 5)
Page 5
Agronomy Matters
(Continued from page 4)
around mid-tillering (GS28) and ended up with 1 tonne/ha of rye grain. When considering the price of cereal rye it looks Grain, Dry Matter, and Gross Margin of grazing cereals - Mannum 2008 1800
160 DM
1600
Grain
140
GM
1400
120
1200
100
1000 80 800 60
600
Gross Margin/ha $$$
kg/ha DM & Grain
Figure 2
40
400
20
200 0
0 Brque 80
Barque 50
Rufus 70
Rufus 100
like a profitable trade. Results from Waikerie and Mannum sites showed exactly the same outcomes. Some other aspects that make cereal rye as a feasible dual purpose cereal option is its early feed production compared to any other types of pasture and high quality of the feed (Figure 3). Also in most occasions cereal rye makes a good break crop if the paddock is experiencing root and fungal disease. Grain quality wasn’t affected by grazing or different seeding/ fertiliser rates, although there were some fluctuations in screenings. At Mannum: Soil test results showed medium level of root disease at the Mannum site, although there weren’t any visible effects of Rhizoctonia and other root disease in the paddock that was thought to be, owing to receiving regular rain and wellbalanced nutrition in the soil. Barque barley was the star with highest feed and grain production compared with other grazing cereals. Due to the price of barley at harvest, gross income of dual purpose barley dropped behind Rufus triticale (Figure 2). Both barley and triticale varieties produced very early feed and carried livestock at the critical pasture shortage time. Barque barley responded to higher seeding rate by 23% higher dry matter production and 67% more grain. Rufus triticale also responded to higher seeding rate by 39% higher dry matter production and 9.5% more grain. Both Wintaroo and Wallaroo oats failed to be a good dual purpose cereal as oats did not respond to grazing very well. Recovery from grazing in oat varieties is not as great as other cereals. It is wiser strategy to graze it at early growing stages and then cut it for hay to get the most out of it. When it comes to feed quality, oats like other cereals has a very high nutritional value and interestingly livestock prefer oats rather than other cereals for grazing (Figure 2).
Oat(hay)
Oat (grain)
Tahara 70
At Wynarka: This site also had a medium to high level of Rhizoctonia with typical Mallee P level and some SU residue in soil from last season. Intention was to compare medic pasture, grazing cereals, a high input pasture such as annual ryegrass with different seeding and fertiliser rates, and regenerating pasture. This site received higher rainfall than average local rainfall which was a bonus. Size of the paddock was 40 ha and grazing completed by sheep in rotational periods. Tetrone annual ryegrass was the best from gross income point of view, then came grazing cereals. Tetrone also had the highest feed quality over all other types of pasture followed by cereal pasture. Pasture trials clearly demonstrated that there is not much increase in dry matter production in medic system when we increased normal district sowing rate (7 kg/ha) to double sowing rate (14 kg/ha), with the same and double rates of fertiliser. To put in a nutshell, 7 kg/ha plus some kick start fertiliser showed the best gross margin from medic system in the Mallee. One of the most important points that we need to keep in mind in a medic pasture system is that the first year is very important, and the main goal should be set on reserving a rich medic seed bank in the soil for the next few years. Therefore grazing periods should be controlled carefully and avoid over grazing particularly around flowering time and a few weeks after that. Generally initial costs of establishing good medic pasture paddock is around 150-160 $/ha in the Mallee (including seed, seed treatment, sowing, chemicals, etc), which is reasonably high for a pasture paddock, but with a good grazing strategy the paddock can be used for many years. Controlling broadleaves and grasses in medic pasture (Continued on page 6)
Volume 6, Issue 1
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system wasn’t as successful as annual ryegrass and cereal pasture, due to limited chemical options and rates. Currently there is some research on spraying Intervix® on Angel medic that is showing promising results especially for Branched Broomrape quarantine area farmers, but yet too early to recommend based on current data. In another part of the Wynarka trial, oats under-sown with medic showed that a cereal cover crop such as oats is a smart choice. Oats provided bulk feed resource from early season reducing grazing pressure, which helped the medic plants to become established and set a rich seed bank in the soil for following years.
Metabolisable Energy (MJ/kg of DM)
This pasture system is a fairly expensive exercise and need 170-180 $/ha input. Long-term feed investment for livestock with early bulk feed on offer in the first year are good reasons to practice this option.
wind erosion especially on hill tops. The best broadleaved and grass control was achieved in the ryegrass pasture system compared with grazing cereals and medic pasture systems. Tetrone ryegrass showed its vigorous growth and competition for nutrition and moisture and reduction in weeds. What does it all mean? After experiencing frequent root disease issues across the Mallee this year, decisions about grazing cereals or any other type of pasture must be made with consideration of minimising root disease populations in your paddocks. Grain and fertiliser prices also add another layer to the process of decision making. Assuming fertiliser prices remain relatively stable in 2009, cereal rye, wheat, barley, and triticale (in order based on profitability) look like a practical and profitable grazing cereal pasture exercise in
Feed Quality of Different Pasture Options in Mallee 14
Figure 3
13.5 13 12.5 12 11.5 11 10.5 Barley
Wheat
Triticale
Rye
Almost all cereals produce bulk quality feed throughout the growing season. Feed quality tests from various locations in Mallee and South Australia shows very minor difference in feed quality of cereals and medic or ryegrass (Figure 3). New annual Italian ryegrass (Tetrone) turned out to be a very high quality and quantity feed. Tetrone proved that it can be sown dry as early as medic, and produced bulk feed throughout the growing season. Tetrone produced ample amount of valuable feed in early summer where Wynarka site received 100 mm of rainfall during November and Tetrone ryegrass regrowth was incredible. This late season feed is of high value due to medic and other pastures having mainly dried off and having nothing to offer. Regenerating weedy pasture is also not reliable for the same reason of moisture stress and in some cases herbicide residue in soil. Generally Tetrone ryegrass is recommended for minimum 350 mm rainfall areas, although our pasture demo sites proved that it can still be profitable in the Mallee region if sown early and under rotational grazing management. Tetrone is extremely frost resistant and has excellent cool season growing making a great winter feed. It provides excellent ground cover which is a great strategy to protect
Oat
Oat& Canola
Medic
Ryegrass
the Murray Mallee, although as mentioned earlier all cereals can be grazed but with higher risk or lower gross income. Early sowing (especially for purely grazing purpose cereals) proved to be a key to increase available early feed for livestock and protect soil surface from erosion. Trials and district practice both are showing that for dual purpose cereals treating the paddock as a crop paddock and stopping grazing around mid-tillering stage do not impact grain yield significantly, and if grazing stops earlier (say 5-leaf stage or very early tillering) there has been no record of yield penalty between grazed and ungrazed cereals. Saying that, grazing any later than late tillering in the Mallee environment increased the risk of losing grain yield by 70%. Feed quality tests also proved that all cereals are of high nutritional value for livestock and potential animal health issues are not considerable. Acknowledgment To Craig Bell, Keith Bolto, Tanja Morgan, Richard Saunders, Linden Masters, Allan Buckley, Peter Blackett, Geoff / Angela / James / Rob Stephens, and anyone else who contributed somehow. AM
MATTERS
Summer edition 2009 - Trials supplement
Pastures profits and broomrape trial 2008 - summary The medic pastures were much less productive than cereals and grasses. There were a number of reasons for this. Establishment was poor, resulting in suboptimum medic density and increased weed competition. Due to the high cost of seed it is not economic to establish plants at high densities. In the first establishment year, seed production for the future should be considered a greater priority than dry matter production.
KEY MESSAGES • Grazed cereals most profitable and aids broomrape control.
• Stocking rates need to be increased to utilise additional feed.
• Medic pastures are a long term investment. • Spray graze unreliable for broomrape control. • Ettrick best all-round performers. The trial consisted of 5 different plots, which were managed by different farmer groups, competing for the most profitable pasture system. Seed, fertiliser and herbicide inputs were varied in an effort to produce the most pasture of highest quality for the lowest cost. For further detail on the trial outline please refer to previous editions of Agronomy Matters. From table 1 it can be seen that the grazed cereals
The theoretical annual stocking rates in table 1 give an indication of the potential for improved pastures to run higher stocking rates. The assumed 100% utilisation and hence 10 DSE on grazed oats and barley may not be achievable. Although with similar utilisations, three times the stocking rate is possible on a grazed cereal when compared to district practice. The additional production and costs per ha associated with grazed cereals are not worthwhile if the extra feed is not used. When grazing more productive pastures, higher stocking rates are needed to turn the additional feed into saleable product. If capital is not available for stock purchase, increasing area used for grain production can increase stocking rates.
Table 1 - production comparisons
Total DM(kg/ha)
Average green feed ME (MJ/kg DM)
Average Crude Protein %
Theoretical Annual DSE/ha average^
Group
Crop
Younghusband
Oats and medic
1902
13.1
18.95
10.1
Ettrick
Cereal rye
1650
12.65
28.3
8.4
Elders/Mypolonga Traders Ryegrass
1776
12.15
15.6
8.6
District practice
Toreador medic
756
11.1
22
3.3
Rural Solutions SA
Angel medic
324
11.4
23.5
1.4
^assuming 7MJME/DSE/day, 100% pasture utilisation, but typically 30-70% (Younghusband and Ettrick) were good performers, producing large amounts of high quality feed. Other trials across the Mallee reinforced the ability of cereals to produce plentiful feed. The Winter Star ryegrass on Elders/ Mypolonga Traders plot was also very productive. Cereal and grass pastures also have the benefit of a wide range of broomrape control options for level 4 paddocks.
It can be seen that the protein content of cereals is high. Young growing stock have the highest requirement for protein, needing 15%. Additional protein is excreted from the animal as waste. Hence the higher protein content of cereals provides no advantage over the protein content of ryegrass and medic pastures. From table 2 it can be seen (Continued on page 2)
Volume 6, Issue 1
Page 2
major sponsors: Hi-fert and Elders.
(Continued from page 1)
that the cost of fodder production ranged from just under $100 to almost $500 per tonne. The lower this cost the better as it means stock can be fed for less. Economically medics were poor performers. However this can be misleading, as it is the year of establishment. The medic pastures have the potential to recuperate some of this years loss over the next few years as production will increase and
We would also like to thank the participating groups: Elders/Mypolonga Traders, Ettrick and Younghusband. During 2009 our attention will be focused on some grazing cereals trials in the Younghusband/Ettrick area, a project funded by National Landcare Program sustainable practices grant. There will also be a pasture trial at the
Table 2 - economic comparisons
Input costs/ha
Cost/tonne DM
Gross income/ha*
Gross margin/ha
Younghusband
$177
$93
$304
$127
Ettrick
$145
$88
$252
$107
Elders/Mypolonga Traders
$208
$117
$259
$50
District practice
$112
$148
$99
-$14
Rural Solutions SA
$149
$460
$43
-$106
Group
*Assuming gross income of $30 per DSE Table 3 - weed control
Broadleaf control herbicide
Broad leaf weeds/m2*
700ml MCPA 500 (Spray graze)
34
3.5g Ally
1
1000ml MCPA 500 (Spray graze)
6
District practice
25g Broadstrike
6
Rural Solutions SA
25g Broadstrike
13
Group Younghusband Ettrick Elders/Mypolonga Traders
* counts taken on 26/09/08, time of potential BBr emergence input costs will be limited to fertiliser. Elders/Mypolonga Traders had the highest input and no relative increase in production. This demonstrated that production is rainfall limited and hence there is an optimum input cost, which produces feed for the least cost per tonne. Ettrick and Younghusband groups were closest to this as they had the lowest costs of production per tonne.
new Brinkley site on Michael Willis’s property. The trial will look at the effect of herbicide type and timing of application on broadleaf weed control in a variety of pasture systems. AM
From table 3 above it can be seen that Younghusband had a high density of broadleaf weeds. The plot was sprayed with 700ml of MCPA 500 on 26th August. This demonstrated the ineffectiveness of a spray graze late in the season. Possible explanations could have been too lage weeds or insufficient stocking rate. Although Younghusband were the most productive and had the highest gross margin, they also had a high risk of broomrape emergence. Ettrick was the best performing group for 2008 as they had a high gross margin as well as good broomrape control. Keith Bolto and Craig Bell would like to thank Phil Dabinett for his time, land and stock. We would also like to thank the
Ettrick’s weed free cereal rye
Volume 6, Issue 1
Page 3
Sustainable and productive pasture systems in the Murray Mallee Final Report summary KEY MESSAGES
Location 1
• Rye, wheat and barley are cereal pasture
Waikerie
options for the feed gap in the Mallee.
• All cereals can be grazed up to the early tillering stage with little grain penalty in the Mallee.
• Cereals provide high quality and quantity feed.
Growing season Rainfall: 140.8 mm Soil Type: Loamy Sand Paddock History: Unsown for last few years
Why grazing cereals? Grazing cereals is not a new technique in mixed farming enterprises, but after intensive cropping took hold it has been used less and less.
Location 2
In low rainfall regions such as the Mallee, grazing cereals seems to be working very well compared to other pasture systems that are not really reliable during feed shortage months (March-July).
Soil Type: Loamy Sand
There is a debate between feeding livestock with A) grain and hay or B) sown cereals for grazing, during feed shortage months. A sown cereal as pasture is a higher input option, but the amount of feed and liveweight gain are significantly higher. Another bonus of grazing cereals is if the season turns out favourably with adequate rainfall, then farmers can get grain yield out of the paddock too.
2006: Pasture
Apart from providing bulk feed for livestock during feed shortage months of the year, early-sown cereals for feed will maintain good ground cover and enhance storage of rainfall in the soil profile. This stored moisture will be used by crops more efficiently as we get closer to the end of the cropping season and will contribute directly to grain yield. Successful farmers’ strategy is to treat their paddock as a crop paddock and graze it rotationally up until early to midtillering, then shut the gate on livestock. If the paddock receives a reasonable rain during July, then there would be a good opportunity for grain harvest, otherwise there always is the option of cutting it for hay. Another successful strategy implemented by South Australian Mallee farmers (especially those who wanted to be on a safer side) is to sow the paddock early merely for feed, and in favourable seasons when they have enough feed on offer in other paddocks they remove livestock from the grazed cereal paddock (before late tillering stage) and turn it into potential grain. In selecting pasture for your farming system there are a few points that need to be taken into consideration, such as
Mannum Growing season Rainfall: 133.6 mm
Paddock History: 2007: Wheat
Location 2
Wynarka Growing season Rainfall: 235 mm Soil Type: Loamy Sand Paddock History: 2007: Wheat 2006: Vetch
when and how much feed you will be needing, quality of feed and possible animal health issues, weed competition and broadleaved weed control (especially host broadleaves in Branched Broomrape quarantine area), fitting into farm rotation to provide early autumn feed and a root disease break for future cropping. In all Murray Mallee research/demonstration sites results proved that all cereals can be comfortably grazed up to their start of tillering (GS 26) without any yield penalty. There has been some difference in yield between grazed and ungrazed areas after their growing stage 28 (late tillering), where in some cereals such as barley, wheat (Continued on page 4)
Volume 6, Issue 1
Page 4
(Continued from page 3)
and rye weren’t as significant and dramatic as triticale and oats. The main tiller in triticale carries the majority of grain and if it gets grazed or damaged by hard grazing, yield will be affected drastically. The same scenario applies to oats varieties and recovery from grazing wasn’t as great as other cereals. Also in grazing oats we have to be careful about weed management strategies as oats is not a good competitor for barley grass, silver grass and brome grass. These weeds can easily take over oats if its growth is set back by grazing. How was the trial done? We had three different sites in Waikerie, Mannum and Wynarka. Diverse varieties of cereals (Barque, Flagship and Maritime barley, Yitpi and Wyalkatchem wheat, Wintaroo
a decision making tool. Rhizoctonia dramatically affected barley varieties, while other cereals (especially rye and triticale) handled Rhizoctonia much better. Total rainfall during the growing season was 140.8 mm which was below average season (Decile 4), combined with June/July moisture and frost stress made a perfect season for failure! Out of all varieties at Waikerie site, rye and wheat performed the best feed-wise and gross income-wise, then came triticale and barley. Under performance of barley was thought to be due to root disease and weed competition later on. The worst was oats that couldn’t compete with weeds after June/July moisture stress.
Grain, Dry Matter, and Gross Margin comparison of grazing cereals- Waikerie 2008 1000
120
Figure 1
100
kg/ha Dm&Grain
800 700
80
600 500
60
400 40
300 200
Gross Margin/ha
900
20
100
and Wallaroo oats, Rufus, Speedy and Tahara triticale, Bevy rye and canola), with various seeding rates (district practice and higher rates) and fertiliser rates tested in Waikerie and Mannum, whilst the main focus of the Wynarka site were on medic and annual ryegrass optimum productivity and seeding rates (Angel and Jaguar medic, Tetrone ryegrass). All sites were sown early and dry (Waikerie on 11th April, Mannum on 3rd May and Wynarka on 15th April). Seeding method was an airseeder with 9” and 12” spacing. Fertiliser rates were 50 and 100 kg/ha DAP at Waikerie, 40 kg/ha DAP at Mannum and 40, 80, 120 kg/ha DAP at the Wynarka site. Grazing method at Wynarka and Mannum were grazing by sheep, whilst at Waikerie site we simulated grazing by mowing the trial to 5 cm height at specific growing stages. What happened? At Waikerie: High level of Rhizoctonia and other root disease at Waikerie trial site reinforced the necessity of soil root disease test as
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Higher seeding and fertiliser rates didn’t perform as expected and there was not a significant difference between district practice and higher rates, which could be due to low level of moisture in the soil at the Waikerie trial site. Out of all dual purpose cereals, wheat varieties showed the best gross income at the Waikerie trial site (2008). Although wheat did not produced the highest amount of feed compared to other grazing cereals, distribution of feed supply during the season was more even (leaning to late feed supply) due to wheat’s winter growing season. Yitpi and Wyalkatchem wheat both showed the same pattern of feed supply, grain yield and close gross income (Figure 1). Cereal rye appears to be a viable option for Murray Mallee hilly and lighter soil paddocks, due to its vigorous growth. Majority of Mallee farmers tend to sow cereal rye merely for grazing, but those farmers who treated their cereal rye paddock as a crop paddock have been harvesting reasonable grain. Their strategy was to keep an eye open for opening rainfall forecast and sow the paddock just before or after that. In a few instances there were farmers who treated their grazing rye as crop, stopped grazing it (Continued on page 5)
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Agronomy Matters
(Continued from page 4)
around mid-tillering (GS28) and ended up with 1 tonne/ha of rye grain. When considering the price of cereal rye it looks Grain, Dry Matter, and Gross Margin of grazing cereals - Mannum 2008 1800
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like a profitable trade. Results from Waikerie and Mannum sites showed exactly the same outcomes. Some other aspects that make cereal rye as a feasible dual purpose cereal option is its early feed production compared to any other types of pasture and high quality of the feed (Figure 3). Also in most occasions cereal rye makes a good break crop if the paddock is experiencing root and fungal disease. Grain quality wasn’t affected by grazing or different seeding/ fertiliser rates, although there were some fluctuations in screenings. At Mannum: Soil test results showed medium level of root disease at the Mannum site, although there weren’t any visible effects of Rhizoctonia and other root disease in the paddock that was thought to be, owing to receiving regular rain and wellbalanced nutrition in the soil. Barque barley was the star with highest feed and grain production compared with other grazing cereals. Due to the price of barley at harvest, gross income of dual purpose barley dropped behind Rufus triticale (Figure 2). Both barley and triticale varieties produced very early feed and carried livestock at the critical pasture shortage time. Barque barley responded to higher seeding rate by 23% higher dry matter production and 67% more grain. Rufus triticale also responded to higher seeding rate by 39% higher dry matter production and 9.5% more grain. Both Wintaroo and Wallaroo oats failed to be a good dual purpose cereal as oats did not respond to grazing very well. Recovery from grazing in oat varieties is not as great as other cereals. It is wiser strategy to graze it at early growing stages and then cut it for hay to get the most out of it. When it comes to feed quality, oats like other cereals has a very high nutritional value and interestingly livestock prefer oats rather than other cereals for grazing (Figure 2).
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At Wynarka: This site also had a medium to high level of Rhizoctonia with typical Mallee P level and some SU residue in soil from last season. Intention was to compare medic pasture, grazing cereals, a high input pasture such as annual ryegrass with different seeding and fertiliser rates, and regenerating pasture. This site received higher rainfall than average local rainfall which was a bonus. Size of the paddock was 40 ha and grazing completed by sheep in rotational periods. Tetrone annual ryegrass was the best from gross income point of view, then came grazing cereals. Tetrone also had the highest feed quality over all other types of pasture followed by cereal pasture. Pasture trials clearly demonstrated that there is not much increase in dry matter production in medic system when we increased normal district sowing rate (7 kg/ha) to double sowing rate (14 kg/ha), with the same and double rates of fertiliser. To put in a nutshell, 7 kg/ha plus some kick start fertiliser showed the best gross margin from medic system in the Mallee. One of the most important points that we need to keep in mind in a medic pasture system is that the first year is very important, and the main goal should be set on reserving a rich medic seed bank in the soil for the next few years. Therefore grazing periods should be controlled carefully and avoid over grazing particularly around flowering time and a few weeks after that. Generally initial costs of establishing good medic pasture paddock is around 150-160 $/ha in the Mallee (including seed, seed treatment, sowing, chemicals, etc), which is reasonably high for a pasture paddock, but with a good grazing strategy the paddock can be used for many years. Controlling broadleaves and grasses in medic pasture (Continued on page 6)
Volume 6, Issue 1
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system wasn’t as successful as annual ryegrass and cereal pasture, due to limited chemical options and rates. Currently there is some research on spraying Intervix® on Angel medic that is showing promising results especially for Branched Broomrape quarantine area farmers, but yet too early to recommend based on current data. In another part of the Wynarka trial, oats under-sown with medic showed that a cereal cover crop such as oats is a smart choice. Oats provided bulk feed resource from early season reducing grazing pressure, which helped the medic plants to become established and set a rich seed bank in the soil for following years.
Metabolisable Energy (MJ/kg of DM)
This pasture system is a fairly expensive exercise and need 170-180 $/ha input. Long-term feed investment for livestock with early bulk feed on offer in the first year are good reasons to practice this option.
wind erosion especially on hill tops. The best broadleaved and grass control was achieved in the ryegrass pasture system compared with grazing cereals and medic pasture systems. Tetrone ryegrass showed its vigorous growth and competition for nutrition and moisture and reduction in weeds. What does it all mean? After experiencing frequent root disease issues across the Mallee this year, decisions about grazing cereals or any other type of pasture must be made with consideration of minimising root disease populations in your paddocks. Grain and fertiliser prices also add another layer to the process of decision making. Assuming fertiliser prices remain relatively stable in 2009, cereal rye, wheat, barley, and triticale (in order based on profitability) look like a practical and profitable grazing cereal pasture exercise in
Feed Quality of Different Pasture Options in Mallee 14
Figure 3
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Almost all cereals produce bulk quality feed throughout the growing season. Feed quality tests from various locations in Mallee and South Australia shows very minor difference in feed quality of cereals and medic or ryegrass (Figure 3). New annual Italian ryegrass (Tetrone) turned out to be a very high quality and quantity feed. Tetrone proved that it can be sown dry as early as medic, and produced bulk feed throughout the growing season. Tetrone produced ample amount of valuable feed in early summer where Wynarka site received 100 mm of rainfall during November and Tetrone ryegrass regrowth was incredible. This late season feed is of high value due to medic and other pastures having mainly dried off and having nothing to offer. Regenerating weedy pasture is also not reliable for the same reason of moisture stress and in some cases herbicide residue in soil. Generally Tetrone ryegrass is recommended for minimum 350 mm rainfall areas, although our pasture demo sites proved that it can still be profitable in the Mallee region if sown early and under rotational grazing management. Tetrone is extremely frost resistant and has excellent cool season growing making a great winter feed. It provides excellent ground cover which is a great strategy to protect
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the Murray Mallee, although as mentioned earlier all cereals can be grazed but with higher risk or lower gross income. Early sowing (especially for purely grazing purpose cereals) proved to be a key to increase available early feed for livestock and protect soil surface from erosion. Trials and district practice both are showing that for dual purpose cereals treating the paddock as a crop paddock and stopping grazing around mid-tillering stage do not impact grain yield significantly, and if grazing stops earlier (say 5-leaf stage or very early tillering) there has been no record of yield penalty between grazed and ungrazed cereals. Saying that, grazing any later than late tillering in the Mallee environment increased the risk of losing grain yield by 70%. Feed quality tests also proved that all cereals are of high nutritional value for livestock and potential animal health issues are not considerable. Acknowledgment To Craig Bell, Keith Bolto, Tanja Morgan, Richard Saunders, Linden Masters, Allan Buckley, Peter Blackett, Geoff / Angela / James / Rob Stephens, and anyone else who contributed somehow. AM
