Strathfieldsaye Estate – Extended Grazing Trial

Year of study:

2007 to ongoing

Lead organisation & Collaborators:

Strathfieldsaye Estate

Contact:

Alan Broughton

soiltest@austlandscapetrust.org.au

Best Available science assessments:

Objectives Hypothesis Design Soil Analysis Production/
Financial		 Method Reporting Data Analysis Results reporting Publication
3 3 1 0 4 2 2 3 2

1=Low, 2=Moderate, 3=High, 4=Very high.

Project details

Objectives:

To demonstrate pasture management techniques that are effective and affordable. Changes are likely to occur over a long period.

Hypotheses:

Extended rest and rotation of stock will:

  • Significantly reduce unpalatable weeds including capeweed, barley grass, rat tail grass, sorrel, fat hen and clammy goosefoot
  • Ground cover will gradually increase to 100% all year
  • increase pasture species biodiversity
  • increase the percentage of perennial species
  • increase the carrying capacity in the long term

Basis of trial:

Sustainable grazing techniques have been trialled and reported on for at least 50 years. Leaders in the field were André Voisin (Grass Productivity) and Allan Savoury (Holistic Resource Management). These rotational systems are similar to those of traditional shepherds and of wild plains animals in East Africa. The height and density of grasses correlates with the depth and mass of roots. When grasses are constantly short, roots are shallow and unable to withstand dry conditions. A plant continually grazed uses its energy to produce leaf; there is little energy left to grow deep roots, exude carbohydrates into the soil to support microbial populations and sequester carbon. Normally grasses deposit about 40% of their carbohydrates into the soil to feed the microbes, which in turn release nutrients from the soil. When this cannot occur, soil structure consequently deteriorates, reducing the ability of the soil to absorb and hold water. Hence drought tolerance decreases. Bare patches develop as perennial species decline and die out, to be replaced by weedy annuals: capeweed, corkscrew and barley grass in the cooler months of the year, and fat hen, clammy goosefoot and purslane in the summer. Capeweed can become dominant in such pastures. Bare soil in summer increases soil temperature which further stresses remaining perennials and soil biology, and causes erosion and water repellence. Palatable perennials are sometimes replaced by unpalatable perennials such as African love grass, sorrel, sweet vernal and rat tail grass. Grazing animals can destroy pasture or restore pasture, depending on how they are managed. Grasses which are allowed to grow to at least15 cm tall, then are eaten to 4 cm in a short time are able to recover quickly, photosynthesise more, sequester more carbon in the soil, and regrow their roots. Generally grass begins regrowing within a few days of being eaten, so grazing should cease by that time in order to allow full recovery. Sustainable grazing practices can more than double annual pasture production, and the benefits can keep on accruing for at least 20 years, according to the literature and farmers’ experiences.

Location details

Trial site details:

The effective grazing area of Strathfieldsaye is about 1,100 ha; the remainder of the property is bushland or low grazing quality grassland that is heavily grazed by kangaroos. Current stock numbers are about 180 cows and calves, 55 two year olds, 170 one year olds and 7 bulls. In June 2011 300 cattle were accepted on short-term agistment to reduce the excess feed.

The 7 soil/pasture types tested were:

  • Deep sand growing bent grass and Sporobolus (rat tail grass)
  • Deep sand growing kikuyu
  • Sandy loam dominated by capeweed
  • Sandy loam dominated by Microlaena and wallaby grass
  • Highly sodic clay growing kangaroo grass
  • Salty soil growing buckshorn plantain
  • Sodic loam dominated by cocksfoot

 

Management practices tested:

Extended Rotational grazing strategies.

Pre-trial management:

Until 2003 the farm ran Merino sheep and a few cattle from time to time. Regular applications of superphosphate and potash were made. The grazing system used is not known but is thought to be similar to district norms that involved minimal rotation. Following the transition to the Australian Landscape Trust from Melbourne University in 2003, the farm was destocked for two years because of the presence of Ovine Johnes Disease – caused by a strain of the bacterium Mycobacterium paratuberculosis. After this time cattle and a flock of sheep were introduced on agistment; but it was drought time and the stocking rate was high. Though obvious damage was occurring due to overgrazing, it was very difficult for management to reduce numbers, because the agisting farmers had nowhere else for their animals to go. Agistment gradually ended by mid 2007 and Strathfieldsaye Estate bought its own herd of cattle during 2007. The carrying capacity of the land was again over-estimated, and this caused further deterioration of pastures in a period of continued drought. Stock were rotated, but remained for several weeks in each paddock until there was nothing left to eat and returned to paddocks as soon as some growth had occurred.

Trial management:

During the first half of 2009 cattle were sent away on agistment in order to reduce the grazing pressure on pastures and in order to ensure their nutrition. By mid 2009 selling had reduced numbers to 187 breeding cows, down from about 450. After the numbers were reduced, it was possible to implement a policy of rotational grazing. In order to practice rotational grazing, the cattle were amalgamated into fewer mobs, paddock sizes were reduced by using one-wire electric fences, short intensive grazing periods were implemented of an average of three days, and long recovery periods for the pasture were instituted, usually no less that four months of rest and often much longer. The costs of paddock subdivision were low because single electric wires were found to be sufficient to contain stock. Moving stock at Strathfieldsaye Estate is also easy and requires no extra work, as they are checked daily anyway; and moving simply requires opening a gate.

Summary of key findings of trial:

Over the course of two years this strategy has produced significant improvements in the pasture:

  • increased ground cover,
  • increased biodiversity,
  • reduction of capeweed,
  • faster recovery after grazing.

Cattle health has also improved.

Most of these changes became apparent within the first year. Rainfall was similar in 2009 to 2008 and did not play a part in these improvements. The improvements have also permitted cattle to be “finished” at Strathfieldsaye Estate, which could not happen previously – this has doubled the value of young stock. The reduced stocking rate has also avoided the drought-related costs of agisting stock elsewhere and buying or making hay.

Lime and trace elements have been applied to some paddocks, with uncertain results. Since 2007 a tonne of lime per hectare has been applied on 220 ha and trace elements (copper, zinc, boron, manganese, molybdenum and/or cobalt in response to indications obtained from soil testing) on 150 of the same hectares. Dung beetles were released in 2009 and have successfully colonised the paddocks, with the result that dung pats disappear within a week. Rainfall in 2010 improved and reached the long term average. It is likely that the better rainfall, dung beetles and applications of lime and trace elements contributed to pasture improvement, but it is thought that this contribution was less significant than the changed grazing management because:

  • Significant pasture improvement occurred before the higher rainfall
  • Pasture improvement was similar in paddocks treated with lime and trace element and untreated paddocks.

Treatment results

 Variation in productivity/profitability with time & management influence:

The following figures include only those relating to the stocking rate, and reflect the gross margin. Wages are included to demonstrate that lowering the stocking rate reduced labour requirements. Feeding equipment is included because it would not have been necessary if cattle were not supplementarily fed. Set costs such as rates, fertilisers, fencing, fuel, vehicle maintenance, organic certification and water supply are not included.

COSTS 2007-8 2008-9 2009-10 2010-11
Vaccines 246 1,748 142 802
Supplements 2,469 457
Vet 2,113 2,586 1,561 396
Feeding equip. 10,877 4,270
Silage making 15,644
Tags, NVD book 1,453 1,248 502 238
Pregnancy testing 343 1,022
Transport for sale 1,188 6,042 924 1,353
Hay, pellets 35,187 78
Agistment costs 21,283
Transport to/from agistment 9,218
Wages 100,802 108,576 56,068 62,172
Total costs 135,135 191,637 59,197 65,039
RETURNS
Sales of young stock (with handling costs taken out) 76,450 137,253 46,142 67,378
# Profit on cow sales (difference between average buying price and average buying price) -2,552 -34,056 -98 -268
# Profit on cow & calf sales (difference between average buying price and average selling 0 -32,200 0
# Profit on sale of bulls (difference between average buying price and average selling price) 0 -7975 0
Agistment receipts 8,989
Total returns 73,898 63,022 46,044 65,670
Balance (returns-costs) -61,237 -128,615 -13,153 631
Young animal sales (weaners & grownrown steers) 186 395 128 64
Average price (net) $411 $347 $360 $1,053

 

# Average cow buying price was $714; average cow and calf buying price: $781. Average cow selling price 2007-8: $656 (44 sold); 2008-9: $516 (172 sold); 2009-10: $616 (1 sold). Average cow and calf selling price 2008-9: $597 (175 sold) (none sold 2007-8 and 2009-10). Average bull buying price: $2,442; average bull selling price $847 (5 sold 2008-9). The figures show that the costs of maintaining a high stocking rate were not recovered by sales. The figures also show that under a more realistic stocking rate animals can be kept longer to more than double their value. Until 2011 stock were sold as weaners 9-12 months old. The animals sold in 2010-11 were about two years old and previously would have been sold the previous year. No weaners were sold in 2010-11; this means a carryover of 50 yearlings and 190 calves to 2011-12, a considerable capital gain. Also not reflected in the figures are the increased pasture and soil carbon banks

 

Other measures of treatment response:

Pasture Quality: The following table shows the increase in ground cover, palatable species and diversity of species over 4 years.

Date Ground Palatable cover % Weeds % Species % Rainfall
2007-8 82 56 26 10 406
2008-9 65 38 27 13 440
2009-10 86 53 33 20 547
2010-11 96 64 32 26 698

The figures above are an average of usually two tests per financial year in each of 15 paddocks. They show a significant increase in ground cover, desirable species and biodiversity since the stocking rate was reduced and rotational grazing policies implemented in mid 2009. In the paddocks where there was a large proportion of capeweed its percentage of ground cover declined significantly; in other paddocks the capeweed percentage remained fairly constant at between 0 and 5%. Full details for individual paddocks are located in Appendix 1.

Feed ahead calculations:  This table shows the amount of feed available and the estimated number of days the feed will last, assuming no growth in the meantime.

Date Kg/ha dry matter * Days of feed
12 March 2009 131,420 87
9 May 2009 210,090 140
4 June 2009 94,360 38
1 July 2009 156,690 52
3 August 2009 113,610 38
1 September 2009 55,270 19
1 October 2009 145,600 48
2 November 2009 501,720 167
1 December 2009 320,540 106
4 January 2010 187,120 62
1 February 2010 148,890 62
1 March 2010 408,830 170
6 April 2010 390,000 162
4 May 2010 312,400 130
10 June 2010 314,680 103
9 August 2010 159,740 53
1 September 2010 158,650 48
1 October 2010 309,840 95
1 November 1010 612,440 185
9 December 2010 658,630 189
1 February 2011 470,720 135
1 March 2011 793,290 277
1 April 2011 905,920 316
3 May 2011 950,540 331
1 June 2011 865,470 255
4 July 2011 581,310 88

Days of feed are calculated by dividing the total available dry matter by the average daily consumption by the cattle on hand at that time. The number of days assumes no growth in the meantime and no change in livestock numbers. The stocking rate for the next few months can be adjusted depending on the length of time the available feed is expected to last.

The long-term goal at Strathfieldsaye Estate is to maintain feed ahead for about 120 days. There are two reasons for this goal: to prevent the need for sudden drastic stock reduction, and to guard against the need for grazing too hard or too soon.

At the end of winter feed ahead can be allowed to contract to less than the ideal in the expectation that regrowth will soon occur; however at other times of the year this is unwise because of East Gippsland’s unreliable climate. Even the relaxation of feed ahead requirements at the close of winter entails some risk as spring rains occasionally fail.

Strathfieldsaye Estate biologists are exploring the principle that maintaining good ground cover and full pasture growth is more important for the economics of the farm than keeping to a predetermined stocking rate. This principle rests on the fact that a decline in pasture quality reduces potential for production in the future. The stocking rate should never be higher than the carrying capacity. However the reverse is not a problem. Large amounts of feed ahead, as has occurred in autumn and late spring 2010 and early 2011 due to good rainfall, are not regarded as a waste but a valuable addition to root depth and soil carbon which will allow greater pasture production in the future and a higher carrying capacity. The stocking rate will be increased to manage the extra growth

 Plant and/or animal production measures:

Since early 2007 records have been kept of the condition of paddocks. Indicators include:

  • percentage of ground cover,
  • ground cover percentage of each of the major pasture species,
  • a botanical list of each species found, and
  • a rating according to pasture quality.

The paddock condition survey is conducted on each paddock twice a year, in autumn and spring. Dates on which livestock entered and moved out are kept for each paddock. A dry matter/ha feed calculation is done each month with two purposes: to determine the carrying capacity for the next few months, and to plan paddock sequencing. The amount of available feed determines which paddocks are grazed next. The amount of available feed varies considerably because of the different productive capacities of paddocks. Paddocks are not overgrazed – stock are removed before grass height is reduced to 4 cm, or when the animals indicate that they want to move. Stock are not forced to consume unpalatable species.

Cost and value of production:

Records are also kept of expenditure and income.

 

Reportage:

How results have been reported:

Internally within Australian Landscape Trust; Evergraze – Field day on pasture management at Strathfieldsaye Article – Bairnsdale Advertiser

How a copy of any relevant reports can be obtained:

Phone 5149 8361, email soiltest@alt.org.au (or soiltest@austlandscapetrust.org.au)

Level of review of results:

No review

Appendix 1: Trends in pasture condition

Long Term Pasture Evaluation Bottom Irrigation 3
Date Cover % Desirable % Weeds % Capeweed % Species Rating
Sep 2008 70 25 45 20 8 Poor
May 2009 90 15 75 10 19 Poor
Aug 2009 80 60 20 5 18 Moderate
Mar 2010 95 20 75 <5t;5 24 Poor
Oct 2010 95 70 25 10 22 Moderate
April 2011 100 50 50 <5t;5 17 Moderate
Long Term Pasture Evaluation Dairy 4b
Date Cover % Desirable % Weeds % Capeweed % Species Rating
Oct 2007 90 55 35 <5t;5 14 Moderate
May 2008 70 65 5 0 7 Moderate
Oct 2008 60 45 15 <5t;5 8 Poor
May 2009 70 45 25 <5t;5 19 Moderate
Aug 2009 80 40 40 <5t;5 17 Moderate
Mar 2010 80 35 45 <5t;5 37 Moderate
Oct 2010 90 60 30 <5t;5 40 Moderate
April 2011 100 50 50 <5t;5 43 Moderate
Long Term Pasture Evaluation East Plain 1
Date Cover % Desirable % Weeds % Capeweed % Species Rating
July 2008 60 25 35 <5t;5 9 Moderate
Oct 2008 50 30 20 0 10 Poor
May 2009 90 65 25 <5t;5 21 Moderate
Oct 2009 90 65 25 <5t;5 19 Moderate
Apr 2010 80 50 30 0 25 Moderate
Oct 2010 95 70 25 <5t;5 22 Good
May 2011 100 90 10 <5t;5 24 Good
Long Term Pasture Evaluation East Two Tanks West
June 2008 80 70 20 <5t;5 5 Good
Oct 2008 60 55 5 0 4 Moderate
May 2009 70 50 20 15 9 Moderate
Oct 2009 80 75 5 <5t;5 11 Moderate
Apr 2010 80 65 15 5 26 Moderate
Oct 2010 80 70 20 5 29 Moderate
May 2011 100 90 10 5 23 Good
Long Term Pasture Evaluation Hartwich’s 1
Date Cover % Desirable % Weeds % Capeweed % Species Rating
May 2008 90 40 50 <5t;5 11 Poor
Oct 2008 50 30 20 5 13 Very poor
Mar 2009 40 30 10 0 13 Poor
Aug 2009 80 55 25 <5t;5 16 Moderate
Mar 2010 90 55 35 5 20 Moderate
Sep 2010 90 80 10 5 17 Good
April 2011 100 75 25 <5t;5 36 Good
Long Term Pasture Evaluation Hartwich’s 5
Date Cover % Desirable % Weeds % Capeweed % Species Rating
Oct 2007 80 60 20 10 13 Good
May 2008 85 40 45 <5t;5 11 Moderate
Oct 2008 60 45 15 <5t;5 21 Poor
Mar 2009 50 25 25 <5t;5 17 Poor
Aug 2009 90 50 40 20 16 Moderate
Mar 2010 90 35 55 5 25 Poor
Sep 2010 90 60 30 20 21 Moderate
April 2011 100 65 35 <5t;5 32 Moderate
Long Term Pasture Evaluation Middle Plain 1
Date Cover % Desirable % Weeds % Capeweed % Species Rating
July 2008 90 30 60 0 6 Poor
Oct 2008 70 20 50 0 6 Very poor
Jan 2009 60 30 30 0 19 Poor
May 2009 80 55 25 <5t;5 16 Moderate
Oct 2009 90 60 30 <5t;5 21 Moderate
Apr 2010 90 50 40 <5t;5 22 Moderate
Oct 2010 95 70 25 <5t;5 24 Good
April 2011 100 65 35 <5t;5 27 Moderate
Long Term Pasture Evaluation Middle Swell Point
Date Cover % Desirable % Weeds % Capeweed % Species Rating
Nov 2007 90 50 40 10 12 Moderate
June 2008 100 10 90 <5t;5 13 Poor
Oct 2008 100 70 30 0 12 Good
May 2009 80 25 55 10 22 Moderate
Sep 2009 95 60 35 <5t;5 21 Moderate
Mar 2010 90 25 65 0 28 Poor
Oct 2010 100 65 35 <5t;5 35 Moderate
May 2011 100 55 45 <5t;5 39 Moderate
Long Term Pasture Evaluation Perry River South
Date Cover % Desirable % Weeds % Capeweed % Species Rating
Oct 2007 80 40 20 30 11 Poor
Mar 2008 60 20 40 30 12 Poor
Sept 2008 60 20 40 20 14 Very poor
Mar 2009 70 35 35 <5t;5 18 Poor
Aug 2009 70 35 35 10 18 Poor
Mar 2010 70 25 45 <5t;5 18 Poor
Sep 2010 80 40 40 10 19 Poor
Mar 2011 95 40 55 5 34 Poor
Long Term Pasture Evaluation Stockyard North East
Date Cover % Desirable % Weeds % Capeweed % Species Rating
Sep 2008 70 40 30 5 14 Moderate
Mar 2009 30 25 5 0 11 Poor
Aug 2009 75 50 25 5 15 Moderate
Mar 2010 90 35 55 <5t;5 18 Poor
Sep 2010 95 45 50 5 17 Moderate
April 2011 100 30 70 <5t;5 19 Poor
Long Term Pasture Evaluation Stockyard South East
Date Cover % Desirable % Weeds % Capeweed % Species Rating
Oct 2007 100 60 40 40 6 Moderate
June 2008 80 40 40 20 10 Moderate
Sep 2008 60 50 10 10 10 Moderate
Mar 2009 40 25 15 10 14 Poor
Sep 2009 80 70 10 5 21 Good
Mar 2010 95 25 70 <5t;5 17 Poor
Sep 2010 95 65 30 20 16 Good
April 2011 100 90 10 5 17 V. good
Long Term Pasture Evaluation Tagasaste 1
Date Cover % Desirable % Weeds % Capeweed % Species Rating
Oct 2007 90 80 10 <5t;5 10 Good
May 2008 95 90 5 0 6 Good
Nov 2008 95 80 15 0 12 Good
Mar 2009 60 50 10 <5t;5 12 Moderate
Aug 2009 100 85 15 5 9 Good
Mar 2010 90 85 5 0 15 Good
Dec 2010 100 90 10 0 21 Good
Mar 2011 100 90 10 <5t;5 25 Good
Long Term Pasture Evaluation Two Tanks West
Date Cover % Desirable % Weeds % Capeweed % Species Rating
June 2008 80 80 0 <5t;5 5 Good
Oct 2008 60 55 5 0 8 Moderate
May 2009 80 55 25 15 14 Moderate
Nov 2009 80 70 20 <5t;5 20 Good
Apr 2010 90 75 15 5 24 Good
Nov 2010 90 80 10 5 29 Good
May 2011 100 95 5 5 23 Good
Long Term Pasture Evaluation West Drive
Date Cover % Desirable % Weeds % Capeweed % Species Rating
Oct 2007 50 30 20 20 5 Poor
Mar 2008 80 40 40 24 15 Moderate
Sept 2008 50 25 25 20 8 Very poor
Mar 2009 40 15 25 <5t;5 14 Very poor
Aug 2009 80 65 15 10 12 Moderate
Mar 2010 80 20 60 <5t;5 25 Poor
Sep 2010 95 60 35 <5t;5 15 Good
Mar 2011 100 65 35 5 31 Moderate
Long Term Pasture Evaluation West Plain 1
Date Cover % Desirable % Weeds % Capeweed % Species Rating
July 2008 70 25 45 <5t;5 9 Poor
Oct 2008 45 15 30 <5t;5 9 Very poor
Jan 2009 60 40 20 0 15 Poor
May 2009 70 55 15 <5t;5 19 Moderate
Oct 2009 95 75 20 <5t;5 26 Good
Apr 2010 95 50 45 0 30 Moderate
Oct 2010 95 55 40 <5t;5 29 Moderate
May 2011 100 50 50 <5t;5 33 Moderate

What recommendations were made about soil/land management and soil health?

Subsequent experience at Strathfieldsaye Estate is indicating that a short intensive grazing period followed by long recovery is beneficial to pasture production and quality.