Future Farm Magazine April 2012

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Perennial mix creates balance CATplus modelling predicts perennial placement for optimal water flow impacts www.futurefarmonline.com.au ISSUE 10 APRIL 2012 farm future INNOVATION IN PROFITABLE PERENNIAL FARMING SYSTEMS in this issue Supported by 14 12 Harvester — from concept to reality Integrated system provides climate buffer 3 Mallee biomass potential takes off

description

Future Farm Innovation in profitable perennial farming systems

Transcript of Future Farm Magazine April 2012

Page 1: Future Farm Magazine April 2012

Perennial mix creates balanceCATplus modelling predicts perennial

placement for optimal water flow impacts

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ISSUE 10 april 2012

farmfutureI N N O V A T I O N I N P R O F I T A B L E P E R E N N I A L F A R M I N G S Y S T E M S

in this issue

Supported by

14

12

Harvester — from concept to reality

Integrated system provides climate buffer

3Mallee biomass potential takes off

Page 2: Future Farm Magazine April 2012

By Peter ZurzoloCeo, future farm industries CrC

A s this copy of Future Farm goes to print, future farm industries CrC

and meat & livestock australia (mla) are holding a workshop on pastures, to bring together industry players and decision makers to consider the future of pasture research in australia.

pasture research is essential. it provides farmers with access to new pasture varieties, improves farm profi tability and productivity and helps farmers stay viable and competitive in the international marketplace.

although initiated and driven by the CrC and mla, the workshop will not only cover these organisations’ research. the future of pasture research in australia is much larger than that.

at this stage, there are 42 participants confi rmed to attend the workshop, representing 17 organisations across all australian states and the aCt. these participants represent all the key industry sectors, including beef, sheep meat, wool and grain.

MLA’s Feedbase Investment Plan defi nes a program of investment in pasture research and development for 2012–16. it is likely that further opportunities for valuable pasture r&D exist and this workshop aims to scope, consider and evaluate those opportunities in line with the federal government’s primary industries standing Committee r&D framework.

Workshop paves the way for adoption

Future Farm magazine is published three times a year by the future farm industries CrC ltd (ffi CrC) aCn 125 594 765.

future farm industries CrC is a unique co-investment between meat, grains and wool industry research corporations, the landmark agribusiness company, and the combined research power of Csiro, seven state agencies and four universities. it was established in 2007 under the Commonwealth government’s Cooperative research Centre program to build on the research of the former CrC for plant-based management of Dryland salinity (CrC salinity).

DISCLAIMER

The information in this document has been published in good faith by Future Farm Industries CRC Limited to promote public discussion and to help improve farm profi tability and natural resource management. It is general information and you should obtain specialist advice on the applicability or otherwise of the information in this document. Neither Future Farm Industries CRC Limited nor any of its Participants endorse the information contained in this document, nor do they endorse any products identifi ed by trade name. The information in this document is made available on the understanding that neither Future Farm Industries CRC Limited, nor any of its Participants will have any liability arising from any reliance upon any information in this document. This document is subject to copyright, and the prior written consent of Future Farm Industries CRC Limited must be obtained before it is copied.

For further information about the CRC visit www.futurefarmonline.com.au

E: [email protected] T: (08) 6488 2505

ISSN (Print) 1835-9906 ISSN (Online) 1835-9914Published April, 2012

Design & production: Kondinin Group

our cover

Supported by

• mallee biomass potential takes off ....................... 3

• mallees prove double-edged sword ......... 4

• location of perennials determines water fl ows ..... 6

• increasing perennials improves production and profi t ...................... 8

• perennial grass options set to expand ...............10

• integrated system provides climate buffer ..............12

• mallee harvester: from concept to reality ..........14

• The fi nal word — tall wheatgrass .............16

contents

ISSUE 7 april 2011

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ISSUE 10 april 20122

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Pasture research is essential to keep pace with current challenges. (Photo CSIRO)

several cooperative research centres, including future farm industries CrC, that either carry out or support pasture research are likely to cease during the next few years. We initiated this workshop to help ensure that the end of these CrCs does not adversely affect pasture research.

I am confi dent the workshop will be a catalyst for further discussion and development of australian pasture r&D and will enable us to build on the great progress already made in this area. i look forward to reporting on the workshop and its implications for pasture research in australia. 8

With careful landscape management and tactical perennial plantings, David strong, tarcutta, NSW has boosted profi tability and groundcover.

• See full story page 8.

photo: pamela lawson

Page 3: Future Farm Magazine April 2012

By Jean Burtonfuture farm industries CrC

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Mallee biomass potential takes off

the next step for the CrC’s Woody Crops program team is to conduct a sustainability study for airbus on mallee as an aviation biofuel. it’s essential to know that mallees are sustainably grown and have low greenhouse gas emissions in order to attract the necessary investment for the future commercial production of the mallees-to-biofuels industry.

Top: Mallee stands on the Alexanders’ property.

Above inset: (Front, L to R) Airbus representative Dr Delia Dimitriu, and GE’s Ben Waters. (Back, L to R) Virgin Australia’s David White and the CRC’s Peter Zurzolo in one of the mallee strands on the Skerritt’s farm.

Below: CSIRO postdoctoral fellow Rick Bennett (left) explains the research being undertaken at the mallee trial site. (Photos: Peter Garside)

• Paul Turnbull, Dpi victoria M: 0409 402 179 E: [email protected]

contact

T he aviation industry’s confi dence in mallee biomass as a source for biofuels

continues to gather momentum.

since last July’s announcement that future farm industries CrC and virgin australia would work together to promote and develop a sustainable transport fuel industry, energy giant ge has come on board, and now aviation giant airbus has joined the group.

the CrC’s aviation partners recently saw fi rsthand the progress being made to develop a biomass industry in regional australia when they toured two farms hosting mallee research near narrogin, south-east of perth, Western australia.

on a hot and blustery march day, the visitors — who also comprised representatives from regional development organisations and government — were shown the work being carried out to evaluate the impact water and nutrient supply has on yield, and the effects of season and harvest frequency.

an open forum provided researchers from the Department of environment and Conservation (DeC) and Csiro, both CrC participants, the opportunity to discuss the supply chain from growth to end use in greater detail.

Woody Crops program leader paul turnbull (Department of primary industries victoria) stressed the importance of having industry in the paddock to communicate the nature and results of the CrC’s research.

“as a result of this mallee tour, the CrC is confi dent its research is playing a vital role in developing a biomass-to-biofuels industry in australia,” paul said.

“the feedback from virgin australia, ge and airbus leaves us in no doubt that they believe mallees will provide sustainable and renewable aviation fuel to keep their planes in the sky in the future. it’s a very exciting time.”

Peter Zurzolo, Chief Executive Offi cer of the CRC, also stressed the signifi cance of the

aviation industry’s presence at the event and thanked farmers for their support.

“it is worth noting that our mallee research, like so much of the CrC’s work, cannot happen without the ongoing support of the farmers across southern australia who allow research trials and fi eld walks to take place on their land. on this occasion, i would like to thank the skerritts and the alexanders for hosting this recent event,” peter said.

“the aviation industry represents a huge driver for mallee biofuel development. to see global aviation leaders in a paddock in the Wa Wheatbelt indicates how seriously they consider the work of the CrC and its partners is to help develop an environmentally sustainable source of biofuels.

“We also acknowledge the industry will take a number of years to fully develop and we understand some farmers’ impatience for tangible success with a mallee industry. However, the CrC and its partners are pursuing a range of industry start-up opportunities to accelerate development. We are confi dent the momentum, underpinned by strong research and our airline partners’ ongoing commitment, is making the reality of mallee harvesting and processing not a matter of if, but when.”

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Mallees prove double-edged swordD on and Kim alexander and

their sons russell and morgan are mallee pioneers. they

planted their fi rst trees during the early days of the mallee industry during the mid 1990s. today there are more than 80,000 mallees on the alexanders’ 4000-hectare wheat-sheep property near narrogin, Western australia. Janet paterson caught up with the Alexanders to fi nd out what the mallees have done for their farm.

“We were initially attracted to mallees because of their capacity to soak up water as we had a big problem with waterlogging on our slopes and salt scalds in our valleys,” Don said.

“We have a lot of york gum country with granite outcrops on the ridges and variable soil depths down the slopes into the valley. left unattended the waterlogging can cause serious erosion issues and salt problems in the lower country of the valley fl oor.

the mallees have helped overcome these waterlogging and salt scald problems as well as contributing aesthetically and attracting a variety of wildlife.

the trees worked really well in terms of drying out the paddocks prone to waterlogging. they also arrested some of

the salt problems we were experiencing — today there are belts of green where once there were salt scalds and we are really pleased with the aesthetic contribution the mallees have made to the property.

the cost of our initial plantings was supported by landcare money and we established about 10,000 trees per year between 1995 and 2003. We explored many different planting layouts, including narrow belts of mallees 60–100 metres apart across the slope, with the intention of intercepting the excess water causing waterlogging and

stopping it from draining into groundwater systems or running down to the valley to contribute to salinisation.

Managing the competitionUnfortunately the mallees have matured and in the absence of any commercial harvest opportunity, the trees have become far too effi cient at extracting and intercepting water. the result is that we are now experiencing competition problems between our crops and pastures, and the mallees in the alleys between the tree belts.

Don Alexander (pictured) is impressed with the ability of mature mallee trees to address waterlogging and rising water tables, but recognises the challenge of investing in a fl edgling biomass industry. (Photos: Peter Garside)

Case study: the alexander family (Don, Kim, russell and morgan)

Location: narrogin, Western australia

Property size: 4000 ha

Mean annual rainfall: 490 mm

Soils: mainly duplex soils and gravel in parts

Enterprises: Wheat, oats, barley, merino ewes and cross-bred lambs

farm info.

• Mallees offer a signifi cant opportunity to manage waterlogging and rising salinity in affected areas.

• As mallees mature, if left unharvested they can compete with adjacent crops and pastures, reducing yield potential.

• A key challenge for the mallee industry is to generate suffi cient commercial demand and supply of biomass to retain farmer and investor interest and commitment.

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We have been involved with a research trial to investigate how various harvest regimes and root pruning the mallees can help reduce this competition, but the results of this work are still being assessed.

basically the research is trying to determine when and how often to harvest the trees to generate the best returns in terms of biomass yield, potential for carbon payments and management of competition.

it is critical this information is gathered to guide future commercial development. there are many farmers with mature mallees eagerly awaiting the capacity to harvest their trees.

While we have been happy with the environmental impacts the mallees have made on our farm we are frustrated with the lack of commercial demand for our biomass. What the industry needs is a commercial scale mallee biomass plant — be this electricity or biofuel or whatever — so farmers can be assured there is money to be made in mallees.

We were happy to see verve’s prototype processing plant being tested in narrogin during 2004, but the absence of any follow-up with an operational plant was disappointing.

basically the mallee industry is in a Catch-22 position — without a market for mallee biomass, farmers are not going to plant

mallees, but until there is enough mallee biomass potential investors in the industry are not likely to commit.

i’m buoyed by the interest the aviation industry is showing in mallee biomass and was heartened to hear that they believe biomass is really the only viable way to generate commercial aviation biofuels.”

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By John Bartle, Department of Environment and Conservation

• The Future Farm Industries CRC research being carried out on the Alexanders’ property is part of a larger project being conducted over 18 widely dispersed locations across the Western Australian Wheatbelt. The project aims to show how different harvest regimes will infl uence yield.

any mallee biomass processing industry needs a reliable year-round supply. Planning a continuous fl ow of biomass will require an understanding of management choices, such as the season and frequency of harvest, and how these infl uence mallee health, yield and profi tability.

Given harvest infl uences the competition imposed by a mallee belt on the adjacent crop or pasture, this is also being measured across the harvest cycle.

We have recently completed analysis of the fi rst fi ve years of data from these trials. this provides the best available information on mallee yield, competition impact and economics.

the results revealed that mallee yield is high enough to give confi dence in being able to achieve commercial yields. However, the competition cost was higher than expected and the relaxation of competition after mallee harvest was smaller and of shorter duration than expected.

Impact of competitionCompetition was measured each year across the mallee harvest cycle as the reduction in crop yield out to 20 metres from the belt. the yield reduction in the unharvested plots was 40 per cent, while in the fi rst year after harvest the yield loss was reduced to 20 per cent. by year

four after harvest competition loss had returned to the unharvested level of 40 per cent.

all yields were corrected to provide estimates for a standard two-row belt (6 m wide with 2 m between rows and a 2 m buffer each side). this was done by making the conservative assumption that, for the half of the trial sites with multiple-row belts, the yield of the outer two rows is the best estimate of a two- row belt yield.

mallee growers have observed strong suppression of inner-row yield in multiple-row belts and trials confi rmed this, where yield of inner rows was as low as 50 per cent of outer rows. such yield contrast within the belt would lead to higher management and harvest costs and provides good reason to prefer two-row belts.

the large competition impact, both on adjacent crops and on inner rows, demonstrates the strong growth potential of mallees. it is plausible that, in multiple-row belts, if the inner rows had not been planted but the wider belt width had been retained, the yield would be the same.

a widely spaced two-row belt confi guration would be cheaper to plant, have all the growth accrued on only two rows, but with less harvest distance to travel and trees would be large enough to harvest more frequently and thereby impose an average lower competition cost on adjacent crops.

Economic analysisthe economic analysis shows that for narrow two-row belts, with the yields and competition losses observed in

these trials, mallee biomass production only breaks even with conventional agriculture in the wetter western areas of the Wheatbelt.

the CrC is planning to establish a series of trials during 2012 to test the assumption that wider two-row belts can produce the same yield as multiple-row belts of the same width. this will allow the evaluation of the economics of two-row mallee belts in drier environments.

Acknowledgements:rural industries research and Development Corporation, avon Catchment Council and australian government funding through the second generation biofuels research and Development grant program provided funds for this project.

The project fi nal report will soon be available on the rirDC website: www.rirdc.gov.au

peck a, sudmeyer r, Huxtable D, bartle J and mendham D (2011) Productivity of mallee agroforestry systems under various harvest and competition management regimes. rirDC project no prJ-000729.

• John Bartle is a researcher with the WA Department of Environment and Conservation with a long involvement with the mallee industry.

• John Bartle, Wa DeC T: 0408 907 762 E: [email protected]

contact

• Don or Kim alexander M: (08) 9882 4030 E: [email protected]

contact

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Page 6: Future Farm Magazine April 2012

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T here is little doubt that increasing the perenniality of land use within a catchment

will lead to improved natural resource management (nrm) outcomes and a likely increase in profi tability. But there has always been a question about what effect increasing perenniality has on catchment water yield, in the form of streamfl ow and the fl ow into farm dams and wetlands.

to answer this question, the future farm industries CrC has instigated and funded the Catplus project.

the project further develops and applies the existing Catchment analysis tools (Cat) model to better predict the effects of perennial vegetation systems on water quality and quantity in a catchment. it models and evaluates the impact of land uses, such as plantation forestry and increasing the perenniality of pasture, on catchment water resources.

Study locationthe Catplus project focuses on two catchment areas — the Wannon River catchment in south-west victoria and the tarcutta Creek catchment in southern new south Wales.

Project leader, Aleksandra Rančić from the Offi ce of Environment and Heritage, NSW, said the project team engaged local expert groups in these two locations to defi ne and test the impacts of various scenarios.

“the local groups are made up of individuals and organisations that provided a wealth of information and data, including current and historical land use, for the two study areas,” aleks said.

“engaging these local experts has increased the understanding and support of model-based approaches to catchment management, and ensures the model outputs back up the activities and outputs of EverGraze.”

Landholder supportaleks is quick to point out that landholders from both the landcare groups in the tarcutta Creek catchment have shown high interest and support for the project.

“they provided all the information requested, including piezometer measurements, rainfall records and the history of land use on their properties, and some contributed to bore monitoring during the project,” she said.

“in the tarcutta Creek catchment, landholders voluntarily provided 90 per cent of the literature and reports produced for this area.

“most landholders are actively involved in landcare and so are aware of problems, such as shallow and rising water tables, waterlogging, salinity and soil erosion. they are often already using practices such as drought feedlots to maintain groundcover, and in the lower parts of the tarcutta Creek catchment, there has been 4–5 per cent increase in native tree cover since 1978.”

The model usedoriginally, Cat was designed to predict the impacts of various land-use scenarios on dryland salinity. it has since been extended to use a range of farming system and forest growth models to link land use, soils, topography and climate data to groundwater systems and streamfl ows on various time and spatial scales.

“the main focus of the modelling at the tarcutta site has been to test the hydrological effects of two potential changes in land use,” aleks said.

“the two land uses modelled are agroforestry tree plantations and perennial pasture establishment, with suitable species determined from trials at nearby EverGraze proof sites.

“the model for this site has been calibrated to refl ect the clearing history and introduction of pine plantations within the catchment. it uses data to create a simulation period of 110 years (1900–2009) and a calibration period of 60 years (1959–2009), as land use in the catchment has been recorded in detail since 1959. this encompasses as much climate variability as possible and provides a wide base for modelling and testing scenarios. this year the calibration period will be extended to

By Pamela Lawson

Location of perennials determines landscape water fl ows

6F o c u s o n R e s e a r c h

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Although planting perennial pastures and trees can reduce water fl ows into dams and streams, the NRM benefi ts will far outweigh the negligible reductions if the plantings are correctly sited. (Photo: Pamela Lawson)

• The CATPlus modelling project uses historical data and current measurements to predict the impact of various land use changes on catchment water yield.

• To have the least impact on water yield, the land use changes must be in the most suitable part of the catchment.

• Tree plantations reduce water yield signifi cantly more than perennial pastures, so are needed to achieve recharge reduction in some catchment areas.

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cover 1949–2011, thanks to more funding being available to access records.

“for the tarcutta Creek catchment, this should allow us to determine the effect on streamfl ow of tree plantations and EverGraze perennial pasture systems being adopted by landholders at various rates. We can also use the model to change land use over time to simulate the effect clearing and pine plantations have had on streamfl ow.”

Streamfl ow changesaccording to aleks, the modelling using Catplus has shown the importance of using the right tool or land use in the right area of a catchment, as the impact of land use varies according to rainfall.

“in low-rainfall parts of the catchment, the land use impacts are local. but in high-rainfall parts they have a general impact on the whole catchment, and even on fl ows that leave the catchment,” aleks said.

“While perennial pastures and trees will indeed reduce water yield, these land uses can be used in areas of the catchment where the reductions in water yield are negligible. the reduced water yield will then be far outweighed by the benefi ts such as recharge reduction, the prevention of waterlogging and salinity, improved soil health and productivity gains.

“the Catplus model has allowed us to run various scenarios and alter the rate of land use change, so we can then provide advice on where in the catchment and to what extent nrm solutions should be applied.”

Recharge results for the tarcutta Creek catchment, the most dramatic results shown by the Catplus

modelling are that 69 hectares of tree plantations situated in zone 2 (see figure 1) would almost halve recharge from 33 megalitres per year to 18 ML/yr.

this modelled plantation area of 69 hectares represents only a small portion of the actual agroforestry plantings in the area, which are estimated to be at least 10 times larger.

the impact of these tree plantations in reducing recharge appears to be very localised, with groundwater trends in Coreinbob being stable, as opposed to the nearby Keajura area where levels are still rising (see figure 2).

the modelling also showed the average fl ow reduction was 0.8 ML/yr which compares to the total average fl ow from the Tarcutta Creek of 160,000 ML/yr. The impact of these plantations on overall streamfl ow was due to the relatively small area of plantation compared with the entire catchment. low rainfall in the lowlands and evaporation from shallow

aquifers also resulted in only a small local yield contribution to the total discharge.

according to the modelling, if the actual area of new tree plantings is 10 (or even 100) times larger, the reduction in streamfl ow would still be negligible at 8 ML or 80 ML respectively.

Importance of positionaccording to aleks, the modelling has also highlighted the importance of looking at the various parts of a catchment when considering where the adoption of nrm solutions (such as tree plantations and perennial pasture establishment) has the most impact on streamfl ow and water yield. the boundaries of the lower, middle and upper parts of the tarcutta Creek catchment as used in the Catplus modelling, are shown in figure 1.

“adopting nrm solutions in the predominantly fl at lower parts of the Tarcutta Creek catchment (zones 1 and 2) would have a very small impact on the streamfl ow. However, increasing perenniality in this area of the catchment would create benefi ts in the form of recharge reduction, prevention of waterlogging and salinity, soil health improvements and productivity gains,” aleks said.

“in the mid parts of the tarcutta Creek catchment (zone 3), nrm solutions can have a considerable impact on water yield and streamfl ow.

“about 10% of this section has problems with erosion, waterlogging and salinity, especially during wetter periods.”

the Catplus modelling recommends EverGraze perennial pasture systems are adopted at a high rate within the boundary of the problem areas. but a high adoption rate outside these areas, especially in the higher rainfall bands, would have a signifi cant,

negative impact on water yield and so is not recommended.

similarly, the adoption of nrm solutions in the upper parts of the tarcutta Creek catchment (zones 4 and 5) would have an extremely high impact on fl ow reduction and so is not recommended.

“if there is an indication of soil degradation due to waterlogging or soil erosion in a specifi c location, increasing perenniality just in this area may be benefi cial, but otherwise the steep country is needed to generate good, clean (low salinity) water yield for the rest of the catchment,” aleks said.

the full Catplus final Technical Report is available on request from Aleksandra Rančić.

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Coreinbob (water table in equilibrium)

Tarcutta Creek near Tarcutta (water table in equilibrium)

Keajura (rising water table)

Zone 4 — Expanding pine plantations (falling water table)

Ground surface

Figure 2 Hydrographs across various groundwater systems in the Tarcutta Creek catchment.

Source: Aleksandra Rančić

Figure 1 The subdivision of the Tarcutta Creek catchment used in the CATPlus modelling.

410047DS

410047BH

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Stream gauges

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10 200 N

Source: CATPlus fi nal report

• Aleksandra Rančić, office of environment and Heritage, nsW

T: 0417 764 115 E: [email protected]

contact

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Increasing perennials improves production and profi tS ince 2004, David strong and

his family have been involved in some signifi cant projects to

create environmental improvements on their sheep and cropping property. but these improvements have also resulted in more profi table and persistent pastures and more productive land, as David recently told pamela lawson.

“located in the lower region of the tarcutta Creek Catchment, we have had problems during the past, with issues such as erosion, waterlogging and salinity,” David said.

“We have mainly used perennial pastures and native tree plantations to try and mitigate these problems in the long-term, and have used both formal and more anecdotal monitoring to document the changes.

First things fi rstbefore embarking on any major endeavours, we made a conscious decision to develop a thoughtful, practical whole-farm plan using the best available information.

While this was tricky to do at the time, it was defi nitely worth putting time into this before we started anything else.

following our farm plan, we gradually carried out a number of improvements including fencing areas of the property according to land class for erosion control, increasing the area sown to perennial pastures for production and groundcover, fencing and planting active gully-lines to trees, and establishing environmental plantings of trees and shrubs on recharge and discharge areas for salt management.

Positive resultsit appears our water table levels have receded signifi cantly where we have sown lucerne-based pastures.

there also seems to be some anecdotal evidence that eucalyptus tree plantings on recharge areas may have resulted in fewer salt scalds in the lower landscape.

the species we planted in these areas of the property include Corymbia citriodora, Corymbia maculata, Eucalyptus polybractea and Eucalyptus sideroxylon.

these observations can be backed up by Catplus modelling, which suggested an agroforestry planting of about 70 hectares in this area of the catchment would halve recharge levels into groundwater without signifi cantly impacting overall streamfl ow.

in reality, the actual area already planted to trees in this part of the catchment is likely

to be at least 10 times that, including over 56 hectares on our property alone.

Shade and shelterin addition to the environmental tree planting, we also undertook fence-line plantings for shade and shelter.

these have proved their worth, especially during weather extremes. then during 2006–07, we established several forestry plantations on otherwise unproductive land, which has potential timber use.

i have been amazed by the growth rates of some of these plantations on gravelly hillsides. However, surprisingly some of the trees on creek fl ats where the soil was deeper and moisture was less limited have not shown the same growth rates. this may possibly be because of water quality and salt issues.

Case study: David strong

Location: ladysmith, new south Wales

Property size: 950 ha

Mean annual rainfall: 600 mm

Soils: red-brown earth, yellow podzolic

Enterprises: Cereal crops (wheat, canola, oats, triticale and lupins), wool and prime lambs

farm info.

• Lucerne-based perennial pastures can help lower water table levels on grazing properties.

• Native tree plantations not only provide shade and shelter but reduce recharge levels and the incidence of salt scald.

• Careful grazing of perennial pastures helps maintain groundcover and keeps the pastures productive and persistent.

key points

As these before (top right) and after (bottom right) photos show, the Strongs (David Strong pictured left) have planted a signifi cant area of their property to trees, which has reduced recharge and resulted in fewer salt scalds in the lower landscape. (Photos: Pamela Lawson and David Strong)

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unclear to what extent this is a result of our environmental work.

Into the futureWhile we have no plans for any additional project work at this stage, we will continue to look for ways to improve our property’s environment.

fencing according to land class has been a great success. it changes the whole way the farm runs so i would certainly do that again.

We are always identifying new areas of the farm we would like to plant trees and shrubs on in the future. We have also got some more diffi cult landscapes we would like to try to establish some perennial pastures on.”

Persistent pasturesWhile lucerne has always been an important component of our pasture, we were delighted to fi nd during the drought years that our own mix of perennial grasses including phalaris, cocksfoot and fescue with sub-clover also persisted well.

productive pastures are an important element of our production as we run predominantly fi ne wool Merino ewes. Depending on their micron and fl eece weight data, they are either joined to terminal sires or to merino sires, so we also need pastures to fatten lambs on.

Fenced offas an additional environmental improvement, we have preserved grassy woodland areas of predominantly native pastures and fenced out regeneration areas we considered had environmental signifi cance for biodiversity.

a team monitoring fauna reported sighting various threatened species at some of our fenced regeneration areas but it is

Maintaining groundcoverWe have also found that the various approaches to maintaining groundcover we have adopted, such as perennial pastures and careful grazing strategies, have had a signifi cant impact on reducing soil loss.

the drought forced us to consider the longer-term environmental impact of some management decisions. We started using drought-lots to feed sheep when groundcover was getting low, to minimise soil loss.

While the drought-lots were a success and served their purpose, i made the mistake in 2006 of making one on a block of land situated on a hillside that was almost non-arable. i discovered that drought-lots are far better situated on arable areas with only a gentle slope for drainage. this makes supplying feed and water to the stock much easier than on more sloping country, and makes it very easy to re-establish cover on this land (usually crop) when the drought breaks. in contrast, we have found it hard to re-establish groundcover on the hillside.

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By Aleksandra Rančić, Office of Environment and Heritage, NSW

• David Strong’s observations are backed up by measurements we have been recording and plotting of standing water level (depth to water in the bore from the ground surface) at 60 bores and piezometers in the Tarcutta Creek catchment, including those on and around David’s property (see Figure 1).

The old bores (GW000841 and GW000863) show that the water table was very deep at the start of the century.

Clearing was mainly fi nished by then and the colonial drought had ended.

increased recharge brought out by the wetter spell of the second half of the century, as well as the land being cleared of its native vegetation, dramatically increased the water table level.

this was documented during 1991 in a report and local bore survey, prompted by waterlogging and salinity problems, which recommended reducing recharge in the area.

since then, the effect of David increasing perenniality on the property is clearly evident. groundwater in the fractured rock aquifer on his property (measured by GW000841) is now eight metres below ground level in spite of heavy rain caused by la nina since march 2010.

When compared with the railway 5 piezometer, located just outside his property, water in all David’s piezometers and bores is signifi cantly lower. It also

takes longer to rise after heavy rain and recedes faster. this is all because perennials evaporate more water than annuals.

• Aleksandra Rančić is a senior natural resource offi cer at Offi ce of Environment and Heritage in Wagga Wagga NSW.

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Figure 1 Graphed readings of bores and piezometers on or local to the Strong’s property

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• David strong M: 0427 284 277 E: [email protected]

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• Aleksandra Rančić, office of environment and Heritage, nsW

T: 0417 764 115 E: [email protected]

contact

Page 10: Future Farm Magazine April 2012

By Catriona Nicholls

10ISSUE 10 april 2012 F o c u s o n R e s e a r c h

future farm

While current seasonal conditions across much of southern australia have

seen many producers face endless weeks of water-logged pastures and pugging by stock, it is the long-term patterns that drive suitable species selection on-farm.

for producers in medium to low-rainfall environments, choice has been sparse when it comes to productive and persistent temperate perennial grass species.

according to Department of primary industries victoria researcher Dr Zhongnan nie, there are precious few cultivars of perennial temperate grasses available in areas with less than 600 mm of average annual rainfall in victoria (winter dominant) and 700 mm in central-northern new south Wales (summer dominant).

“While the past few seasons have been favourable, a substantially below-average rainfall year is a signifi cant threat for pasture plants to persist and produce in these areas,” Zhongnan said.

Above: A group of farmers visiting one of the genotype by environment (GxE) experiments at Eversley, Victoria.

Below right: Improved cocksfoot varieties will offer producers in low-rainfall regions a productive and resilient perennial grass pasture option. (Photos: Zhongnan Nie)

Perennial grass options set to expand

“the inland slopes of the great Dividing range between western victoria and northern nsW are mostly in this marginal zone for perennial grasses. for instance, in the southern nsW livestock-cropping zone, lucerne is currently the predominant commercial perennial but has a number of drawbacks including low groundcover and intolerance to acidic or waterlogged soils.”

replacement of annual-dominated pasture with perennials over large areas has the potential to improve seasonal feed supply, increase ground cover and resilience to climate variability, and reduce risk of dryland salinity.

“We expect the new grasses developed from this project will signifi cantly improve pasture yield, persistence and nutritive value, and expand the area of improved perennial pastures sown in the target environments where current commercial cultivars do not adapt,” Zhongnan said.

Verge of changeafter more than eight years of research and development across two project phases, funded by meat and livestock australia (mla) and then future farm industries CrC, the Improved perennial grasses project is on the verge of commercialising two new perennial grass options — improved cocksfoot and tall fescue varieties — with project collaborator Heritage seeds.

“When you think of the big four temperate pasture grasses used across southern australia you have perennial ryegrass, phalaris, cocksfoot and tall fescue,” explained Zhongnan.

“but while these options work well in the high to medium-rainfall zones (900–600 mm), there are few cultivars of perennial grasses

that are well adapted to the medium to low rainfall area (<600 mm) environments.

“and while cocksfoot, tall fescue and phalaris have potential for these areas, commercially available varieties just haven’t been persisting during dry seasons.”

Decisions on commercialisation of phalaris varieties will be made when more data has been collected from this project.

Facing the challengeto start the search for varieties with the ability to adapt to drier conditions, researchers identifi ed potential accessions from a large pool of germplasm sourced worldwide from areas with similar environmental parameters such as the mediterranean basin and north africa.

“We then established a breeding program (during 2004) using about 80 lines of cocksfoot and 120 of tall fescue at a range of sites across victoria and northern nsW,” Zhongnan explained.

“For the fi rst two years rainfall was reasonable across the sites, but 2006 was very dry across much of southern australia.

“in one of the sites in central victoria we had about 275 mm annual rainfall and really tested the plants. many died, but some lines survived quite well, so we dug up the best plants, brought them back to the breeding chamber and crossed them.

“from there we developed four cocksfoot lines and three tall fescue lines.”

• New temperate perennial grass pasture options for medium to low rainfall environments are about to increase.

• Commercialisation is underway for three new lines of cocksfoot and tall fescue.

• The new pasture varieties could see positive impacts across more than seven million hectares of grazing land in southern Australia.

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Page 11: Future Farm Magazine April 2012

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these lines, together with new phalaris lines bred by Csiro, were then evaluated in a genotype x environment (gxe) experiment in phase 1 of the CrC project. phase 2 of the project has seen researchers continue the established gxe experiments to identify the persistence and productivity of these lines compared with commercial cultivars.

“We sowed our elite lines (three new tall fescue, four cocksfoot and fi ve new phalaris lines) into fi ve sites in Victoria and southern and northern nsW and compared their performance against relevant controls,” Zhongnan said.

“the objective is to identify whether the new lines are doing better than the controls.”

Data has been collected for more than two years (see sample data for cocksfoot in table 1), but evaluation of potential new perennial grass cultivars for commercialisation requires the experiments to continue for at least two more years to determine the lines’ persistence.

persistence will be monitored annually, and pasture yield and composition monitored at least once per season.

seed production of the cocksfoot and tall fescue experimental varieties from the isolation blocks will continue at Hamilton and glen innes. seed increase of the phalaris cultivar selected for commercialisation will be undertaken by Csiro starting in 2013 and continuing until the end of the project.

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11ISSUE 10 april 2012

• Dr Zhongnan Nie, Dpi victoria T: (03) 5573 0791 M: 0429 868 011 E: [email protected]

contact

Table 1 Dry matter production (tonnes per hectare) across experimental and control lines of cocksfoot (2009–2011)

Cultivar/line Bealiba, Victoria

Eversley, Victoria

Beckom, southern NSW

Trungley Hall, southern NSW

Inverell, northern NSW

Currie replacement 10.1 15.3 12.0 5.9 11.3

AVH48 12.2 18.3 9.8 1.6 8.7

Cocksfoot fi ne 7.0 11.7 13.3 6.9 6.1

Cocksfoot very fi ne 5.8 9.7 12.9 6.1 5.5

Currie 7.7 12.9 6.7 3.2 10.6

Kasbah 4.0 7.6 3.5 2.3 2.3

sendace 5.5 9.7 3.9 0.8 3.5Note: The table shows the total sown grass herbage production (DM t/ha; 2009–2011) for cocksfoot cultivars/lines from the genotype x environment experiments across fi ve sites in Victoria and NSW (trials were sown during autumn–winter 2009 except the Inverell trial, which was sown during winter 2010). The fi rst four lines are the new lines (Currie replacement, AVH48, cocksfoot fi ne and cocksfoot very fi ne) developed by the CRC.

To be successful in the marketplace requires more than

just clever genetics and breeding — there needs to be commercial savvy to pave the way to on-farm adoption. This is where commercial seed company, Heritage Seeds comes into the Improved perennial grasses project.

Heritage seeds has been involved with the project right from the start and for Heritage seeds product Development manager, Dr John evans, the approach makes perfect sense.

“our collaboration on this project is a great example of the sum of the parts being greater than the whole,” John said.

“in terms of developing genetics and breeding programs from scratch, commercial companies, like Heritage seeds, often can struggle to justify such an investment — particularly with species such as cocksfoot and tall fescue that have limited marketability on a global scale.”

“However, in a lot of respects the commercial companies are specialists in taking new products, such as these temperate perennial grasses, to market once the breeding and evaluation has been done.

“it’s a case of using the strengths of the different organisations — we understand the commercial realities and have a strong perspective of market need and the CrC

Partnering for success

• Dr John Evans, Heritage seeds M: 0413 442 810 E: [email protected]

contact

and its team have the ability to do the all-important groundwork.”

As such, John believes the CRC benefi ts from Heritage seeds’ strategic input in the early stages in terms of market knowledge — knowing what the market is likely to want and accept.

“We also have the ability to undertake seed production when the genetics have been fi nalised and the expertise in taking a product to market,” he said.

Bulking upHeritage seeds is now in the process of ongoing fi eld evaluations and bulking up the amount of seed for the two lines of cocksfoot and one of tall fescue, with the aim of having a marketable supply available by 2014, when the CrC winds up.

“We will put the grasses into seed production for the next two years, which will give us a limited supply of commercial seed to work with,” John said.

While this seed production process is underway, the CrC team will develop practical agronomy packages to promote the varieties to advisors.

Weed risk note: future farm industries CrC assesses the

risk pasture species may pose to native ecosystems.

CrC researchers have completed weed risk assessments for tall fescue, cocksfoot, and phalaris. tall fescue has a medium weed risk in Wa, sa and nsW and a low weed risk in victoria. Cocksfoot has a high weed risk in Wa and a medium weed risk in sa, victoria and nsW. phalaris has a high weed risk in Wa, sa and nsW and a medium weed risk in victoria.

management guides for phalaris and cocksfoot are available on www.futurefarmonline.com.au

Page 12: Future Farm Magazine April 2012

Integrated system provides climate bufferThe highly variable seasons of

recent years have prompted Woomargama Station

manager, Chris mirams to scrutinise his feedbase. the result has been an appreciation of the true value of his native pastures and the development of an integrated pasture system that matches species to landscape under a well managed grazing strategy.

“Historically our long-term average rainfall is a fairly reliable 750 mm, but during the eight years of drought the average rainfall was 600 mm. the past three years have been extraordinarily variable — in 2009 we had 520 mm and in 2010 we had 1120 mm,” Chris said.

“the challenge has been to develop a farming system that copes with this variation and makes the most of any rainfall, regardless of when it falls.

the answer lies in an integrated, productive and permanent pasture system and sound, evidence-based decision making.

Situation snapshotWe are faced with highly variable soils across our landscape. about one third of the property is arable and we maintain well-fertilised, improved pasture species.

more than half the property is steep, with relatively infertile shallow soils, which maintain various amounts of native pasture and natural timber.

about 10 per cent of the property has been planted to interconnecting tree plantations, particularly along creek lines, gullies and in fragile areas.

Managing for potentialDuring the late 1980s a whole farm plan was prepared, which has been the blue print for much of the property development. most of the property has now been subdivided into land classifi cations and we manage each paddock to its potential.

During the early 1990s our grazing system (both improved and native pastures) centred predominately around spring growth and set stocking. the improved country made up 35 per cent of the country and carried 80 per cent of the stock.

our native areas carried mainly dry stock, at 2–4 Dse. the pastures were managed poorly, the stock did not do particularly well and the area contributed little.

With low stocking rates and poor pasture utilisation we usually had plenty of residual spring feed to get us through the summer and autumn, supplemented with hay until the

following spring — we would curse summer rain, as it destroyed the dry standing feed.

During the mid 1990s we increased stocking rates signifi cantly and changed from autumn to spring lambing and calving providing more mouths to consume feed as it grew.

Matching pasture with livestockmatching pasture availability to lactation is highly desirable, however our summer and autumn periods became much tougher, particularly for the weaners.

We were reluctant to supplementary feed — we needed a pasture system that grew grass all year round.

our immediate initiative was to sow hundreds of hectares to a wide range of species with varying growth habit, including phalaris, cocksfoot, lucerne, chicory, plantain, winter and summer fescues, perennial ryegrass, white clover — the list goes on.

Chris Mirams (pictured) has developed a fl exible and resilient pasture system that integrates native (pictured) and improved species to match pasture growth and livestock requirements year round. (Photos: Gill Fry)

Case study: Chris mirams

Location: Holbrook, nsW

Property size: 2700 ha

Mean annual rainfall: 750 mm (with great variation)

Soils: alluvial and heavy clay flats running up to steep shale

Enterprises: fine wool merinos (10,000 hd) and beef cattle (1000 hd)

farm info.

750 mm (with great variation)

12ISSUE 10 april 2012

future farm

S t o r i e s f r o m A u s t r a l i a n F a r m e r s

• Integrating improved and native pastures offers fl exibility and resilience in livestock systems.

• Matching pastures species to the landscape yields long-term increases in production and persistence.

• Timely fertiliser management supports both introduced and native species and promotes desirable species throughout the year.

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Page 13: Future Farm Magazine April 2012

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phalaris heavily, while the native pastures enjoy a rest.

During summer, when the phalaris is dormant, the summer-active natives earn their keep. Our rotations are flexible and we focus on what is happening in the paddocks rather than adhere to strict rules.

We now manage a suite of drought-tolerant, productive and perennial grass pastures, which respond to rainfall all year round.

Right species — right purposephalaris and sub clover pastures are the backbone of our system, providing the bulk of our high-quality feed, but our native pastures now play a key role.

the limited area of lucerne makes it challenging to manage a large number of lambs through summer and autumn and our flock structure reflects this.

Our wethers provide the flexibility to destock quickly in tight times, even though they don’t match the pasture growth curve well — they reduce the cost of production for our wool enterprise.

perennial ryegrass helps fatten steers, provides high-quality feed for lambs and fills the silage pits. However, these pastures are short lived (and expensive) under our conditions and are limited to small areas of our best country.

superphosphate to stimulate clover growth, which provides nitrogen that feeds both the native and annual grasses improving pasture yield and quality.

We initially stocked the area with 4000 wethers, but found prolonged periods of low protein and low digestibility impacted on wool quality and livestock condition regardless of the amount of food on offer.

We tried all sorts of supplementary remedies for this, including licks, blocks and lupins — they proved expensive and unsatisfactory.

eventually we came up with the simple solution of integrating improved and native country in the same rotation, with the aim of lifting the average quality of the feed intake.

We now have three grazing blocks, one for the ewes, one for wethers and one for cattle — each block includes 15 to 20 existing paddocks, some improved pasture and some native pasture.

the native pastures are an ideal low-cost environment for running adult cattle and the hill country helps prevent calving problems.

the improved pastures come into play to get the cows to the right weight for joining. Calves are weaned onto the best pastures with maximum growth rates for steers until they are sold during December at about 440 kg. We run heifers on improved pasture until the start of their third trimester (may) when we put them up into the hills to maintain bodyweight and control further foetal growth.

for much of the year it is a continuous rotation, however, during spring we graze the

We undertook a major liming program, initially applying lime to the surface and direct drilling an acid-tolerant species, with the aim of sowing phalaris after the lime moved down through the soil profile.

this worked well and more than 200 hectares was renovated each year, typically doubling the carrying capacity.

We fertilised the improved pastures annually, aiming to build the phosphorus levels to >30 pp (Colwell). We then apply an annual maintenance rate of 0.8 kg of phosphorus per Dse. Carrying capacity currently ranges from 14 to 20 Dse across the improved pastures, with typical superphosphate rates of 130 to 180 kg/ha per year.

Despite a move to rotational grazing and the practice of destocking into sacrifice paddocks in tough times, during the course of the drought hundreds of hectares of cocksfoot, fescues, chicory, plantain and perennial rye withered and died.

We have discovered there are really only three permanent (perennial) pasture combinations for our system — phalaris and sub clover, native grasses and a bit of lucerne. We also realise how important perennial pasture is and how costly non-permanent pasture can be.

Native potential realisedWhile we focused on sowing the latest cultivar, we were distracted from using what we now know to be one of our great resources — our native grasses.

The main beneficial grasses are wallaby grass (Austrodanthonia spp.), weeping grass (Microlaena stipoides) and red grass (Bothriochloa macra). We applied 80 kg of

future farm

• Chris mirams E: [email protected]

contact

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By Kate Sargeant, DPI Victoria

• The key feature of Chris’ system is his use of different pasture types and landscapes across the farm for his different livestock systems.

Woomargama Station has three main pasture types distributed across the most appropriate landscapes — native pastures and sub clover on steep hill country, phalaris and sub-clover on undulating country, and high-performance pasture (lucerne, short-term ryegrass and brassicas) on the alluvial flats. interconnected tree lots meet aesthetic and environmental objectives.

each livestock enterprise is allocated blocks or cells of a combination of native and improved pastures, which are rotationally grazed and rested at strategic times to meet both livestock nutritional demands (especially to maximise reproductive performance) and pasture production and persistence targets. the high-performance pastures

are reserved for growing stock, allowing Chris to run self-replacing and finishing enterprises.

Holbrook Proof Siteat the Holbrook proof site, production targets were met by strategically grazing phalaris and sub clover and fertilised native and sub clover pastures in an ‘integrated’ management system. this system was significantly more profitable (in most price scenarios) than running separate flocks of ewes and lambs on phalaris and sub clover and wethers on fertilised native and sub clover pastures.

modest phosphorus applications are important to maintain a sub-clover population and feed quality in the native pastures, meeting nutritional targets of the ewe/lamb enterprise. Running a single flock of ewes and lambs was also important to increase grazing pressure when needed during spring growth on the native pastures and keep the annual

component (stimulated by the fertiliser) under control.

reducing stocking rates at the end of spring, by selling store lambs in the proof site system, meant grazing could be restricted to the phalaris, allowing the native pastures to set seed. the subsequent increase in feed during summer allowed for grazing of the native pastures during autumn or early winter. this approach allows a feed wedge to be developed on the phalaris. in Chris’ system, this same objective is met using the high-performance pastures for finishing growing stock.

• Kate is the National EverGraze Project Leader, based at DPI Victoria in Benalla.

• Kate Sargeant, Dpi victoria T: (03) 5761 1598 E: [email protected]

contact

Page 14: Future Farm Magazine April 2012

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By Janet Paterson

Mallee harvester: from concept to reality

14F o c u s o n R e s e a r c hISSUE 10 april 2012

The mallee harvester works! the prototype harvester, developed by richard sulman, biosystems engineering, with ongoing support and

advice from future farm industries CrC project leader rick giles, has now met all its milestones and work on developing a commercial model has begun. this is a huge boon for the embryonic mallee industry as a harvester is an essential component of an integrated supply chain for woody crops. in this article, we review the challenging road that has taken the harvester from concept to reality.

The development of a harvester for the Australian mallee industry started 15 years ago with several years of work by Harley Pederick of Dumbleyung Engineering and the CRC’s Rick Giles, leading to a concept harvester (above). The next challenge, which would take most of the next decade, was to develop a harvester that could cut and chip mallees at a commercially viable rate (left).

The mallee’s form and size requires a unique harvester design. Mallees are not a conventional single-stem forest plantation tree, nor are they a forage crop. Therefore, developing a mallee harvester needed to draw on both agricultural and forestry harvesting principles.

To be commercially viable, the harvester needs to be able to harvest and chip the mallee stems continuously at a rate of at least 50 green tonnes per hour. This requires the harvester to operate on the move and trees have to be harvested and fed into the chipper while standing up. In conventional forestry systems, individual stems are felled then stockpiled for later processing.

The mallee’s form and size requires a unique harvester

To be commercially viable, the harvester needs to be 2

3

The development of a harvester for the Australian mallee industry started 15 years ago with several years of work by Harley Pederick of Dumbleyung Engineering and the CRC’s Rick Giles, leading to a concept harvester (above). The next challenge, which would take most of the next decade, was to develop a harvester that could cut and chip mallees at a commercially viable rate (left).

The development of a harvester for the Australian The development of a harvester for the Australian

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Designing a system to cut, queue and carry vertical stems along a conveyor to the chipper was a huge engineering challenge, especially given that mallees are multi-stemmed, irregular and have very dense wood.

Initially augers (left) were used to grab and transport the stems but these were replaced by chain elevators (right), as they proved more aggressive and effective. Richard Sulman, Biosystems Engineering, (right) designed the successful mallee harvester.

After extensive investigations, a chipper was developed that uses 45 per cent less energy than its predecessors.The early-commercial harvester currently being developed will have about 600 kW of power with most of this going through the chipper. The current harvester (pictured above) is based on a 280 kW tractor.

Chipping the mallee stems requires considerable energy and minimising the power used by the chipper has been a major consideration during the harvester’s development.

Designing a system to cut, queue and carry vertical

Initially augers (left) were used to grab and transport

After extensive investigations, a chipper was developed that

Chipping the mallee stems requires considerable energy and minimising the power used by the chipper has been a major consideration during the harvester’s development.

Initially augers (left) were used to grab and transport the stems but these were replaced by chain elevators Initially augers (left) were used to grab and transport

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Optimising the strength and weight of the saw disc ensured it cut the mallee stems with the greatest possible effi ciency. The momentum of the spinning disc is set so it cuts each stem without wasting energy in needless spinning. Improving the operational effi ciency of each of the harvester’s components was critical because there is limited power to drive each harvesting process.

Optimising the strength and weight of the saw disc

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The greatest diffi culty was engineering the transfer of the vertical tree stems from the elevator to the rollers that feed the trees into the chipper. This required the moving trees to change direction from moving up the incline to dropping vertically down into the chipper. It is imperative the tree stems are not left uncontrolled for even a split second during this process or they may fall from the machine.

The greatest diffi culty was engineering the transfer of the vertical tree stems from the elevator to the rollers that feed the trees into the chipper. This required the moving trees to change direction from moving up the incline to dropping vertically down into the chipper. It is imperative the tree stems are not left uncontrolled for even a split second during this process or they may fall from the machine.

5

During 2012, the prototype mallee harvester successfully met its fi nal milestone — to harvest at least 20 tonnes per hour for at least an hour. in fact, it achieved a harvest rate of 38 tonnes per hour for 74 minutes. The harvester trials also provided valuable information on the bulk density of the chipped material, which will underpin the design of future transport systems for the mallee industry.

the next step is to develop an early commercial harvester to produce the fi rst commercial volumes of biomass and promote the technology to commercial manufacturers.

• Paul Turnbull, Dpi victoria M: 0409 402 179 E: [email protected]

contact

Page 16: Future Farm Magazine April 2012

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Please return this form to:Future Farm Industries CRCThe University of Western Australia M08135 Stirling Highway, Crawley WA 6009Tel (08) 6488 2505 Fax (08) 6488 2856Or email: [email protected]

w w w . f u t u r e f a r m o n l i n e . c o m . a u

Supported by

tall wheatgrass (Thinopyrum ponticum) has been offi cially

gazetted a ‘threatening process’ in victoria. the victorian government gazette listed invasion of vegetation by tall wheatgrass as a threatening process in february this year.

Weed risk researcher Christine munday (Wa Department of environment and Conservation), said it was not surprising this had happened.

“tall wheatgrass is a productive plant in some agricultural systems but is also an invasive weed in some natural environments in south-eastern australia,” Chris said.

“it can be highly competitive, forming monocultures and reducing biodiversity.”

the CrC’s formal weed risk assessment showed tall wheatgrass has a high weed risk to native environments in parts of Western australia, new south Wales and south australia and a very high weed risk to some native environments in victoria.

“Where tall wheatgrass is used in agriculture, the most effective way to manage it is to control its spread and seed production. When it is used as a pasture plant, frequent grazing or mowing will help limit seed set and maintain nutritive value and palatability,” Chris said.

“tall wheatgrass should not be planted in victoria. in other areas, where the weed risk is still high, alternative, less invasive, and preferably native, species should be considered to fi ll the agricultural niche.”

the CrC’s weed risk assessment and management guide for tall wheatgrass are available at www.futurefarmonline.com.au/about/weedrisk.htm

The fi nal word