Project Update April 2014

Biofuel feedstocks as co-products on dairy farms: income and sustainability benefits

Project Update. Period: January to April 2014

Chris Littlejohn, Bio-Protection Research Centre, P O Box 85084, Lincoln University. p: +64 3 325 3838 extension: 8639 Mob. +64 2108204285
Funders: Westland Milk Products Ltd. and DairyNZ, + support from AgResearch and Lincoln University

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Season Two

Miscanthus (Mxg) growth

Second-season Mxg shelterbelts

Under renewed irrigation, following repair in November of the centre pivot damaged in the September gales, growth rate of established Mxg shelter has remained impressive with paddocks 21 (Fig.1) and 6 reaching an average height of 2.0 m and 1.8 m, respectively, by mid-February. Maximum height for both shelterbelts was 2.3 m. Expected maximum height at the end of season 2 is 3 m so despite early setbacks from no irrigation during the spring drought these Mxg plants demonstrated impressive growth rates.


Fig.1: Miscanthus x giganteus (Mxg) shelterbelt; Paddock 21, Aylesbury Farm, Feb 17, 2014.

Mxg shelter in paddock 22 has also continued to show good recovery from the severe early season setbacks of drought and vehicle damage during pivot repair. Despite no visible growth until mid-November average height is now 1 m without any loss of plants. It will be interesting to see how this year’s reduced growth affects next season’s performance.

New planted Mxg shelterbelts

The average height after 3 months growth for the new plantings this season is 35 cm for paddock 12 and 24 cm for paddocks K2 and K3. Average height for all paddocks at this stage last season was 50 cm. K2 and K3 are both irrigated with a rota-rainer and have had reduced irrigation compared to the centre pivot used elsewhere on the farm. This shows the necessity of adequate irrigation for attaining high yields in Canterbury. The rota-rainer delivers 36 mm each pass but was irrigating paddocks only every 8 days. On dry windy days evapotranspiration rates would be higher than the average daily amount of water applied and the soils would be in a state of negative water balance. This was reflected in soil moisture readings which were as low as 12% by volume 0v on some occasions. This also illustrates the benefit of sheltering pasture from the effects of drying winds. The centre pivot at Aylesbury farm delivers a higher application rate of water and soil moisture levels of paddocks irrigated with the centre pivot never drop below 25% by volume.

The new plantings in paddock 12, although not yet under the centre pivot due to delay in replacing the end boom, have had adequate irrigation due to K-lines being installed and were one third taller than those in K2 and K3. Mxg plantings last season also performed better than these plants and this may be a reflection of higher sunshine and temperatures. Good establishment is important as research indicates that poor first season growth can delay attainment of maximum yield potential; however by season 5 planting density and initial growth are no longer limiting factors (Danalatos et al 2007).

Shelter effects on pasture growth


Fig.2: Differences in grass growth between (a) unirrigated and (b) irrigated areas, Aylesbury Farm, Dec 30, 2013.

After repair of the centre pivot pastures recovered quickly from drought (Fig.2) and shelter benefits on pasture growth started to become apparent. C-Dax readings taken at the end of February showed an increase in yield of 12% in the area of paddock 21 sheltered by the Mxg plants and in paddock 6 the yield increase was 10%. One possible driver for this is that leaves of pasture plants sheltered from the wind keep their stomata open longer, shown by a higher rate of stomatal conductance, due to reduced effects of water stress. As a result, they photosynthesise longer, resulting in more growth.

Stomatal conductance measurements were taken using a porometer (Fig.3) during late spring and summer and the results show that during drying northerly winds there is a higher level of conductance in sheltered clover plants. Clover leaves were chosen as they fit the measuring chamber better than ryegrass leaves. Fig. 4 shows average readings taken between 11.30 h and 15.30 h in paddock 21 on 23 January 2014. A strong north-westerly wind was blowing and the average temperature was 19 0C.


Fig.3: Decagon porometer used for measuring stomatal conductance.


Fig.4: Differences in stomatal conductance between sheltered and open-paddock area. Paddock 21, Aylesbury Farm on 23rd January 2014.

Improved pasture yield

Using data collected from C-Dax pasture readings AgResearch produce maps illustrating the heights of pasture across the paddock. Fig.5 was produced from C-Dax readings taken from paddock 21 on 14 February 2014. Dots on the map indicate where readings from the C-Dax have been taken. The shelter area and control area are 40 m by 40 m in size and this is where concentrated C-Dax readings are taken. These areas have also been used to collect soil samples, pasture quality samples and record dung pat numbers post grazing. Comparing these two areas gives a direct comparison of pasture production with and without shelter. The remainder of the paddock is measured by passes of the C-Dax approximately 10 m apart and this provides a record of pasture growth over the whole paddock. Fig.5 shows that pasture height is highest near to the Mxg shelterbelt and also a possible shelter effect can be seen in the form of higher grass growth extending out from the shelter area.


Reduced evapotranspiration rates

Mobile data logging equipment has been built by Lincoln University technician Stephen Stillwell and this is being tested in the University nursery (Fig. 6) before being placed on farm. By using the meteorological data this collects and interpreting these data using the Penman equation for calculating evapotranspiration rates comparisons between sheltered areas and open paddock can be performed.


Fig. 6: Mobile data logging equipment for measuring evapotranspiration rates.

Cattle and shelter

One of the unanswered questions surrounding the provision of shelter for cattle is do they actually use it? Events at the beginning of March, when there was wet weather and a severe southerly winds blowing for three days, go some way to resolve this. When placed in paddock 21 for the night, most of the cows congregated at the northern end of the paddock as they turned their backs to the wind and walked until they found shelter or could not go any further.


The consequences, as illustrated in Fig.7, were severe pugging of the paddock and as the cows broke into the Mxg shelter, they stripped the leaves from the plants. The advantage of having Mxg as a shelterbelt in this case is that it will regrow and these plants have already started to produce leaves. Also, despite the 300 to 400 cows trampling through it, most of the stems remained upright. More importantly is the loss of production from the pugged pasture which could be as much as 30% over a season.

The fact that the cows behaved in exactly the same way the next day in a paddock with no shelterbelt shows they do walk away from the prevailing wind. However if the Mxg had been planted all around the paddock, and was at its full height of 4 m, the cows may have been sheltered enough from the southerly wind to not walk to the northern end of the paddock. When the springers (cows due to calve) were put into paddock 21 the next day, they did turn their backs to the wind but also made use of the limited shelter (due to early-season damage) afforded by the Mxg shelter in paddock 22 (Fig.8).


Fig.8: Cows sheltering from a southerly wind in paddock 21, Aylesbury Farm, 2 March, 2014.

Presentations and media promotion

On January 27 a group from DairyNZ, hosted by Ina Pinxterhuis, PhD, Senior Scientist, South Island, visited Aylesbury Farm to find out how Mxg can benefit dairy farms and become an integrated component of the farming system. This was organised as part of DairyNZ’s funding agreement which involves passing on information about this research to the wider dairy industry.

In February I gave a talk on our research at the 2nd National Conference on Biological Farming Systems at Rotorua, 20 – 21 February 2014.This was well received and generated considerable interest, the furthest of which was from a delegate based in Malaysia. Since then we have Mxg enquiries from Iran.

On 13 March TV3 News filmed Prof. Steve Wratten and I (Fig.9) at Aylesbury Farm for a news item on our Mxg research. This was screened on March 17.


Fig.9: Chris Littlejohn and Steve Wratten being filmed for TV3 News, 13 March 2014.

As a follow-up to this news coverage and as a ‘teaser’ for the Open Day which will be held at Aylesbury Farm on 14 May, Steve Attwood,(Convergence) representative for Westland Milk Products Ltd., is organising a press release to further promote this research. The Open Day will be primarily aimed at invited representatives from the dairy industry and associated interested organisations including banks. Another more farmer oriented Open Day will be held next season.

Journal submissions

A journal article on the ecosystem services (ES) and ecosytem dis-services (EDS) provided by Mxg as a shelterbelt on dairy farms is being prepared with a view to submission late winter. This will analyse a number of ES (e.g., improved pasture production, reduced irrigation need, improved pollination rates) and EDS, (e.g., flammability, pugging), and an attempt will be made to provide a monetary value for these. Helping with this will be Katie Bicknell, Senior Lecturer in Economics at Lincoln University, and it is great that Katie has offered her expertise for this.


I wish to acknowledge those who have given their support to this project, in particular the funding from Westland Milk Products Ltd and DairyNZ, and the welcome assistance and equipment from AgResearch. From all the media attention the work is receiving it is clear that this work is novel and of high potential.


Danalatos NG, Archontoulis SV, Mitsios I (2007) Potential growth and biomass productivity of Miscanthus×giganteus as affected by plant density and N-fertilization in central Greece. Biomass and Bioenergy 31, 145-152.

Project Update January 2014

Biofuel feedstocks as co-products on dairy farms: income and sustainability benefits

Project Update. Period: to January 2014

Chris Littlejohn, Bio-Protection Research Centre, P O Box 85084, Lincoln University. p: +64 3 325 3838 extension: 8639 Mob. +64 2108204285
Funders; Westland Milk Products Ltd. and DairyNZ, + support from Agresearch and Lincoln University

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Season Two



Fig.1: Miscanthus plants December 30, 2013; Paddock 21, Aylesbury Farm. Planted December 2012.


Centre Pivot damage: effects on Miscanthus growth

As anticipated in Newsletter 10, damage to the Centre Pivot at Aylesbury Farm caused problems with some early-season Miscanthus (Mxg) growth but fortunately severe damage has occurred only with the shelterbelt in paddock 22. Pivot repair was finally completed on December 8 but due to part of the pivot falling onto the Mxg shelter in paddock 22 many of the plants were driven over during repair (Fig. 2). Plants were severely affected as illustrated by the difference in growth between those in paddock 22 (Fig. 2) compared to those in paddock 21 (Fig.3).


Fig.2: Damage to Miscanthus plants; Paddock 22, Aylesbury arm, Dec 8, 2013.


Fig.3: Growth with irrigation; Paddock 21, Aylesbury Farm, Dec 8, 2013.


The lack of irrigation on Aylesbury Farm was compounded by the fact that spring was very dry with only 20 mm of rain falling in November and only 7 mm in the last half of October. Soil moisture levels had fallen below that necessary to maintain grass growth by the end of October, ranging from 6 to 15 % by volume (0v) at this time. Fig. 4 illustrates the soil moisture profile for paddock 22 and expected values for wilting point and field capacity.


Fig. 4: Calculated soil moisture release curve for Paddock 22 Aylesbury Farm, generated using soil pressure plates.

Soil water content held at low tension, present in macro and micropores, is readily available to the plants. Once the soil has reached field capacity any remaining water is held within micropores. As these pores are emptied, roots will draw from progressively smaller pores in which matric water potential is lower and the forces attracting water to soil surfaces, water tension, are greater. Therefore it will become more and more difficult for plants to remove water from the soil at a rate sufficient to meet their needs. At wilting point any soil moisture is held at too high a tension for the plants to extract and is unavailable to them. The soil moisture profile for paddock 22 shows that once soil moisture level falls below 22 % 0v any remaining moisture is unavailable to the plants. The soil becomes fully saturated at 36 % 0v and so the soil only holds 14 % 0v of available water. This, plus the fact that soil depth over most of the farm is between 24 and 35 cm and the farm often experiences dry windy conditions means the soil has low water storage ability and soon dries to wilting point in the absence of rain or irrigation. One of the potential benefits of the presence of Mxg shelterbelts will be to protect pasture plants from this drying wind and increase pasture production.

The fall in soil moisture levels meant some form of irrigation was needed and this was provided in part by establishing a network of K-lines across the farm. This allowed partial irrigation of parts of the farm which caused as well as solved problems for this research project. Paddock 21 miscanthus plants received 200 mm from K-line irrigation in November 2013 and consequently growth from this shelterbelt has been vigorous and uniform as illustrated by Figs.1 and 3. Most of the plants in this stand are now between 1.6 and 2 m tall. In contrast, paddock 6 picked up some moisture from irrigation on a neighbouring paddock on its northern boundary. The outer, northern row of plants grew relatively unhindered but other plants in the stand hardly grew at all (Fig. 5).


Fig.5: Uneven growth; Paddock 6, Aylesbury Farm, Dec 17, 2013.

Mark Williams, Aylesbury Farm owner, kindly agreed to transfer some of his K-lines to irrigate the whole of the paddock 6 Mxg area for two days. This, as well as the subsequent pivot repair and high December rainfall has led to improved growth of previously water-stressed plants. Most are now between 1.1 and 1.5 m tall and plants across the shelter area now appear more even (Fig.6).



Fig.6: Miscanthus growth; Paddock 6, Aylesbury Farm, Dec 30, 2013.


Paddock 22 has also now started to recover. During pivot repair it received no irrigation which resulted in the plants remaining dormant, which helped to minimise trampling damage from workmen and machines. All plants, even those that appeared dead, now have green shoots emerging and those that were not trampled have grown rapidly (Fig.7).


Fig.7: Miscanthus growth; Paddock 22, Aylesbury Farm, Dec 30, 2013.

Centre Pivot damage: effects on pasture growth

One of the consequences of installing K-lines only in certain areas of Aylesbury Farm is that resulting uneven grass growth will potentially mask any benefits of shelter effect on grass growth (Fig.8). Since drought effects were experienced only for one month, there should be no significant long-term effects in grass production. To check this, C-Dax pasture readings and dry matter cuts were taken at the end of the drought period and these will be used when analysing subsequent grass growth readings later in the season.



Fig.8: Differences in grass growth between irrigated and unirrigated areas, Aylesbury Farm, Dec 30, 2013.

Effects of Mxg plantings on biodiversity

As stated in Newsletter 10, to give information on the extent of weed management necessary to allow unhindered crop growth, winter weed control in Mxg plantings on Aylesbury Farm involved only removal of weeds immediately surrounding Mxg plants and at Springston Farm there was no weed control. Removal of all weeds would be normal practice to maximise crop growth however establishing ground cover between Mxg plants can help to develop habitat beneficial for insects. The vigorous nature of Mxg growth, particularly year three onwards, eliminates the need for weed control after season two. Results here indicate that removal of weeds immediately surrounding Mxg plants is sufficient to allow unhindered crop growth in season two as illustrated by Fig.9.

Since Mxg grows vertically rather than laterally, an open canopy exists at ground level, particularly in young stands. In a narrow strip this allows light penetration and ground cover plants to grow. In two of the three new paddocks that were planted on the 16 December 2013, Acaena inermis ‘purpurea’ (Rosaceae) plants will be planted amongst the Mxg plants to provide nectar and pollen for beneficial insects and to determine if these plants will survive in this environment.


Fig.9: Minimal weed removal has allowed Mxg plants to grow unhindered while allowing a ground canopy to develop. Paddock 21, Aylesbury Farm, Dec 30, 2013.


Bumble bee motel occupancy and skink refuge use

Bumble bee motels were restocked over the winter. In half of the compartments Pink Batts were used, the remaining half being stocked with a woollen blanket material. Previous research by Barron et al 2000 shows occupancy improves in season two and three after placement. Last season, no motels were used as nesting sites and this season only two out of 48 motels were occupied. Both compartments used contained Pink Batts, and both motels were in sheltered locations in paddock 6, one being in the Mxg shelterbelt and one in a thick gorse hedge. Hopefully next season an improvement in occupancy rate will be seen.

Skink refuge areas are starting to be used but only those placed within the Mxg. An intensive survey of occupancy rate will take place in March 2014.

Update on data logging equipment

Equipment to detect stomatal conductance in pasture plants and to monitor water-stress levels has arrived and is being calibrated for use in February 2014. The equipment will be set up on mobile trolley system and will be placed in the control and sheltered areas of paddock 21. The canopy temperature will then be used to directly indicate plant water stress levels in real-time and at the same time, soil moisture levels will be monitored. This work will provide information on whether water stress is reduced by shelter and also provide information on optimising irrigation efficiency.

Open Day

The open day which was provisionally organised for February 20, 2014 at Aylesbury Farm has been delayed due to the irrigation problems. This will now take place in late March or April and when the date is confirmed notifications will be sent out. In the meantime, a team from DairyNZ will be visiting trial plots on January 27th and a new date will be set soon after this.


Thanks to those that have given their support to this project, in particular the funding from Westland Milk Products Ltd and DairyNZ, it is much appreciated. With the new plantings in December 2013 there are now six irrigated paddocks with shelterbelts in. This should enable sufficient data to be collected on the ecosystem benefits of using miscanthus as a shelterbelt crop on dairy farms. My 15 month report was completed and assessed favourably in November 2013 and a literature review is underway which will be submitted to relevant journals.

Happy New Year
Lincoln University


Barron MC, Wratten SD, Donovan BJ. 2000. A four year investigation into the efficacy of domiciles for enhancement of bumble bee populations.

Agricultural and Forest Entomology 2: 141-146

Project Update September 2013

Biofuel feedstocks as co-products on dairy farms: income and sustainability benefits.

Project Update. Period: to Sept 29, 2013

Chris Littlejohn, Bio-Protection Research Centre, P O Box 85084, Lincoln University. p: +64 3 325 3838 extension: 8639 Mob. +64 2108204285
Funders; Westland Milk Products and DairyNZ, + support from Agresearch

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Spring Update; Season Two


Fig.1: Miscanthus plants September 7, 2013; paddock 22 Aylesbury farm.

Crop News

The first signs of re-growth started to appear at the beginning of September. Stems that senesced over the winter remained soft and did not stiffen to produce harder stems, as had been expected (Fig.2).


Fig.2: Last summer’s stems after moving their nutrient content to the rhizome; paddock 22, Aylesbury Farm, Oct 7, 2013.[/mks_one_half]


Fig.3: Leaf growth from the top of previously-senesced stems; paddock 22, Aylesbury Farm, Oct 7, 2013.


This may be a feature of first season’s growth or may have been a consequence of the relatively mild winter resulting in a slower rate of nutrient transfer. M. x gianteus (Mxg) is not harvested in its first season but when considering future harvest date research (Lewandowski and Heinz 2003) shows energy yield is reduced the later the harvest date, due to nutrient content decreasing as nutrients are translocated to the rhizome. Interestingly some of these stems greened up again in September and initially produced leaves (Figs. 3 and 4) but these died back during a period of frosty mornings.


Fig. 4: Greening of Miscanthus stems; paddock 6, September 7, 2013 Aylesbury Farm


Fig.5: Miscanthus shoots first appeared at the beginning of September; paddock 21 Aylesbury Farm.


Early September also saw the first appearance of new shoots (Fig 5). Frequent frosts and a lowering in soil temperatures kept any further regrowth in check until the end of September when significant sprouting and growth from the base of plants was visible (Fig.6).


Fig.6: Vigorous growth from Mxg plants; paddock 6, Aylesbury Farm, Oct 1, 2013.

Whether this spring growth is again is checked by late frosts will be interesting to see. Zub and Brancourt-Hulmel’s (2009) research on crop production in Europe suggests frost tolerance is a breed trait that needs to be improved if Mxg is to be produced in colder regions. Their research indicates susceptibility to winter frost at temperatures below −8 °C for rhizomes and −3.5 °C for young shoots of Mxg can lead to significant plant losses and lower yields. Research by Lewandowski et al (2000) also indicates that in the first winter following planting, the rather shallow and under-developed rhizomes can often be damaged or destroyed by cold and or wet conditions. There are no reports of over-wintering problems in the second and subsequent winters. This year’s relatively mild Canterbury winter should prove to be a bonus to this season’s plant growth and well developed shelterbelts should be the outcome from those Mxg plantings in irrigated paddocks. This is providing that the damage caused to the centre pivot at Aylesbury Farm by the recent storm that hit the region on the September 10 (Fig.7) is repaired before water stress levels become too severe. The immediate area surrounding Aylesbury Farm suffered extensive tree damage, something that would not occur with Miscanthus shelterbelts at this time of year as above ground material would have been harvested or senesced. With harvested plots no stock shelter would be available but with senesced plants some shelter protection is still present.

If high Mxg yields of 30 Tonnes-1 ha or more are to be achieved in the Canterbury region then lasts years growth studies, where irrigated plants were on average a metre taller than unirrigated ones, indicates that irrigation is essential. The observations of frost effect on young growth also suggest that in particularly cold winters mulching may be necessary to mitigate any crop damage in the first winter.


Fig.7: Damage to the Centre Pivot at Aylesbury Farm, September 12, 2013

Effects of Mxg plantings on biodiversity

Research in Europe (Semere and Slater 2006) showed that since perennial rhizomatous grasses require a single initial planting and tillage only at time of planting, and also no major chemical inputs, and where the crops are harvested in the spring and the land is not disturbed by cultivation every year, the fields were used as over-wintering sites for invertebrates, suggesting immediate benefits to biodiversity. Similar studies have also shown variable benefits for woodland bird species depending on canopy density, weediness and stage of growth. Winter weed control has been minimal in Mxg plantings on Aylesbury Farm and only the removal of any weeds at the base of each plant was performed once sprouting had been observed (Fig. 5). In the only one remaining Mxg planting on Springston Farm, which is partially irrigated, there has been no weed control to see if Mxg plants will push through the existing weed cover. This will give information on levels of weed control necessary to allow unhindered crop growth. All the remaining plots which were unirrigated and had poor growth last season have had blanket spraying of a broad leaved herbicide to remove weed so as to help initial growth of these weaker plants.

Research work over the winter months

Winter months have been spent analysing base-line data which will be used to benchmark any shelter effects in the coming seasons and preparing progress reports. Further soil analysis has been undertaken and soil moisture profiles prepared. This will form an important part of analysis of varying pasture water stress levels due to shelter effect. Bumble motels have been serviced and restocked with bedding material and baseline earthworm counts have been taken. A fifteen month progress report has been submitted to Lincoln University and this will be supported by a presentation on 20 Oct 2013.

DairyNZ provide funding support

One successful outcome of winter activities has been a successful funding application to DairyNZ for data-logging equipment. The allocation of $25,000 will be used to purchase real time monitoring equipment which will be used to assess pasture water stress using canopy temperature as an index. Plants suffering water stress will close their stomata which results in an increase in leaf temperature due to reduced evapotranspiration. This can be detected using infra-red thermometers and used to calculate stomatal conductance. Equipment will be set up to try and achieve this and a hand held porometer, which directly measures stomatal conductance, will be used to calibrate readings. The canopy temperature will then be used to directly indicate plant water stress levels in real-time and at the same time soil moisture levels will be monitored. This work will provide information on whether water stress levels are reduced by shelter and also provide information on optimising irrigation efficiency.

DairyNZ will also help promote methods of best practice for growing Mxg on dairy farms which will also be generated by this research. This contribution is very much appreciated and complements the support provided by Westland Milk Products.

Open Day

An open day has been organised for 20 February 2014 at Aylesbury Farm to provide information on the agronomy of Mxg, research results gained so far and to illustrate the shelter effect of Mxg as by then it should be 3 m high. The aim is to illustrate, using existing plantings, how miscanthus can fit into the dairy production system. Westland Milk Products and DairyNZ will be helping to organise the day. Specialists from DairyNZ, Westland Milk Products, Agresearch and Lincoln University will be present. DairyNZ will be assisting in producing publication material and a BBQ will be provided. A reminder will be posted nearer the time but please put the date in your diaries.

The future of Miscanthus in New Zealand

Negotiations and planning are well under way between Lincoln University and a Californian company to develop in New Zealand a small-scale, portable unit which makes 150 litres-1 hour of renewable diesel. The ‘drop-in’ renewable diesel can be made, through a catalytic process, from any cellulosic material, including miscanthus, cardboard, paper, straw etc. This product can be used as boiler fuel or for transport and has been approved by the state of California as a road fuel with no further treatment – unlike biodiesel from plant oils where transesterification is needed. Prof. Steve Wratten of the Bio-Protection Centre at Lincoln University and Peter Brown from Miscanthus New Zealand Ltd will have a meeting with the California Company later in October.

Chris Littlejohn


Lewandowski I, Heinz A (2003). Delayed harvest of miscanthus—influences on biomass quantity and quality and environmental impacts of energy production. European Journal of Agronomy 19, 45-63.

Lewandowski, I. , Clifton-Brownb,I., Scurlockc,J. and Huismand,W., (2000). European experience with a novel energy crop. Biomass and Bioenergy Volume 19, Issue 4, October 2000, Pages 209–227

Semere, T et Slater F.M (2007). Invertebrate populations in miscanthus and reed canary-grass. Biomass and Bioenergy 31 : 30 – 39.

Zub, H. and Brancourt-Hulmel, M (2009 ) Agronomic and physiological performances of different species of Miscanthus, a major energy crop. A review Agronomy for Sustainable Development, Volume 30, Number 2, April 2009 , pp. 201-214(14)

Project Update July 2013

Biofuel feedstocks as co-products on dairy farms: income and sustainability benefits

Project Update. Period: To July 3, 2013

Chris Littlejohn, Bio-Protection Research Centre, P O Box 85084, Lincoln University. p: +64 3 325 3838 extension: 8639

Mid-winter Update

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Fig.1: Senescence of Miscanthus giganteus (miscanthus) plants, 1.5 m high, at the end of June 2013; paddock 22 Aylesbury farm.

Crop News

Miscanthus plants are now starting to senesce and pass nutrients to their rhizome (Fig. 1). First year-yields are not worth harvesting and so the remaining woody stems will stay in place until new growth commences next spring.

Miscanthus planted in the irrigated paddocks of Aylesbury Farm achieved a maximum height of 1.5 m which is impressive considering the late planting and initial lack of irrigation. This growth was achieved from initially water-stressed plants in just four months. Expected height from growth over seven months was 1 m. Normally above-ground growth in the first year is not very extensive as most development is occurring underground in the rhizome. Strong rhizome development in the first year is very important in determining subsequent yield. The impressive above-ground growth achieved indicates the plants have equally impressive rhizome development and that next year’s growth should easily reach the anticipated 3 m in height which is needed for testing the multi-functional nature’s services generated by its role as a shelterbelt and biofuel source.

Initially miscanthus was chosen for its ability to create shelter rapidly and of a significant height and also because of its ability to let the centre pivot to pass through it. The fact that it shows signs of providing exceptional yields is a bonus. The high yield and low input demand are the main factors why recent analyses conclude that miscanthus, in the (warm) temperate zone, is the bioenergy crop that seems able to deliver the highest net GHG mitigation. The highest net energy output was also found when peak, pre-senescence, yields were harvested. Sustainability of many first-generation biofuels – which are produced primarily from food crops such as grains, sugar cane and vegetable oils – has been increasingly questioned over concerns such as reported displacement of food-crops, effects on the environment and climate change. This increasing criticism has raised attention to the potential of so-called second-generation biofuels of which miscanthus, specifically M. giganteus, is an example. While second-generation biofuel crops and production technologies are more efficient, their production could become unsustainable if they compete with food crops for available land. The advantage of integrating miscanthus within the farming system is that the crop complements the existing farm production and is synergistic with it.


In mid-May I was invited to give a presentation on my research to date at the Bioenergy Association of New Zealand (BANZ) Conference on ‘Unlocking additional revenue from traditional rural land use’ in Rotorua. This was well received and showed how well our research fits into the present direction that ‘future farming’ in New Zealand should be taking. Farmers can be conservative in terms of change, and adopting new farming systems will mainly be achieved only if farmers can be confident in the financial benefits and outcomes of doing so. With the (perhaps token) commitment of governments to reduce carbon emissions, the need to develop bio-energy crops to replace fossil fuels is a necessity. The advantage of using miscanthus is that until carbon credits etc. become a viable market, the crop has existing multiple uses, as feed or bedding material, shelter, wildlife and pollinator habitat and as a useful agro-ecologically based marketing tool.

Pasture Yield Analysis

Sheltered areas of the paddock potentially have higher pasture production and quality. Part of this research is to investigate if this is the case. Pasture samples collected from miscanthus-sheltered and unsheltered areas of paddocks throughout last season are being analysed for digestibility, nutrient and energy content. Results will be used to determine base data for comparing any changes next season resulting from shelter. Thanks to Samuel Dennis’s team at Agresearch, yield maps based on pasture height readings collected last season using a C-Dax pasture meter have been produced. An example of one of these is illustrated in Fig.2.


Fig.2: Grass yield expressed as plant height from paddock 22 on Aylesbury farm 22 Jan 2013.

Every black dot represents a pasture height record from the C-Dax pasture meter. Concentrated readings are taken from the area immediately enclosed by the miscanthus shelter and from an equivalent-sized control area from the open paddock. The rest of the paddock is measured by towing the C-dax up and down the paddock at 10 metre intervals. The height readings are used to generate a map of pasture height over the whole paddock as illustrated by Fig.2. These will be repeated immediately before and after each grazing event over the next two years. Results from six paddocks planted with miscanthus will be used, each with a control area at least 150 m away from any shelter and of equivalent size to the area immediately enclosed by miscanthus shelter. The control areas have been chosen to reflect as close as possible the physical features; soil depth, position relative to the centre pivot, proximity to paddock boundary and topography of the sheltered area. To interpret whether the presence of shelter has influenced pasture production changes relative to base values Before After Control Impact (BACI) analysis will be used. There will be six replicates with full irrigation. Three further paddocks with no or partial irrigation will also be measured.

Open Day

In July we are hoping to organise an open day at Aylesbury Farm. The aim is to illustrate, using existing plantings, how miscanthus can fit into the dairy production system. When the date has been finalised I will send an email to notify all recipients of this newsletter.

Thanks again to all the funders and helpers who have and continue to assist in this research.

Chris Littlejohn
Lincoln University

Project Update April 2013

Evaluation and Enhancement of Ecosystem Services on Dairy Farms

Project Update. Period: To April 9, 2013

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Arrival of Autumn


Fig.1: MxG plantings at Aylesbury Farm

Growth of irrigated plants has continued to be impressive at Aylesbury farm with some now over 1.5 m tall. Karetu farm received its first significant rainfall since February 6 on March 19 with 26 – 30 mm of rain over two days. This resulted in what were apparently dead MxG plants sprouting new shoots, indicating the robustness of this plant. Recent rainfall in early April brought about further new vigorous growth as illustrated by fig.3. In comparison the Poplar trees next to the MxG plantings, Fig.2, shed their leaves long ago and may not have survived.

The amount of new growth of the MxG plants at Karetu varies greatly as illustrated by figs. 4 and 5. Plants planted on November 27, 2013 have a higher number of plants exhibiting rapid re-growth compared to those planted on December 6, 2013. This indicates that planting earlier in the year would result in the majority of plants being able to survive summer drought conditions. What is surprising is that, even with planting so late, many plants have survived the drought especially considering the poor soil conditions found here. Fig. 6 shows the soil profile at the location of the MxG shelterbelt.This is typical of the Lismore soils found in this area which are characterised by very shallow deposits of silty loess covering a very stony substrate.


Fig. 2: Poplar trees next to the MxG plantings at Karetu farm.



Fig. 3: New growth from MxG plantings at Karetu farm.


Fig.4: MXG plants at Karetu showing early signs of new growth.


Fig. 6: Soil profile below MxG planting area at Karetu farm.



Fig.5: MxG plants at Karetu showing recent rapid growth.


Weed control in MxG Shelterbelts

At Aylesbury farm, where MxG plantings have been constantly irrigated since 23 December, weed and MxG growth have continued to be vigorous. To investigate whether, in these conditions, weed competition limits MxG growth a small trial was set up. Eight similar sized areas in each of three of the MxG plantings were marked out. Four of these areas were sprayed, (Fig 7), with Turfix, a broadleaf herbicide not toxic to MxG plants, and four were left unsprayed, (Fig 6). After four weeks, over which time the MxG grew 1 cm a day, the height of twelve plants in each treatment plot were measured. This resulted in half of all the plants in each of the MxG shelterbelts being measured. The mean height differences between sprayed and unsprayed plots is illustrated in Fig. 8. The mean height of plants in the unsprayed plots was 104.9 cm and that of the sprayed plots was 105.3 cm. This indicates that well established MxG plants on irrigated dairy farms are vigorously competitive. It does not mean that weed control is unnecessary; in fact all plantings needed spraying in the early stages, especially to prevent smothering by fathen (Chenopodium album). However it does indicate that once a certain height is reached, and in the absence of other stresses such as drought, the deeper rooting MxG plant is less prone to the effects of weed competition.


Fig.6 : Unsprayed area of MxG shelterbelt in paddock 21 at Aylesbury farm.



Fig.7: Sprayed area of MxG shelterbelt in paddock 21 at Aylesbury farm.



Fig. 8; Bar chart showing mean MxG plant height in sprayed and unsprayed plots 30 days after spraying.

Future implications of spray trial

In dense stands of MxG the rapid plant growth soon shades out any plants growing between the stands. In the case of shelterbelts which are narow linear plantings, there may be enough light penetration to allow the growth of desirable ground-covering plants.

One of these is Acaena inermis purpurea, (Fig 9), an endemic New Zealand plant species. It has been used successfully in vineyards where it spreads well, does not compete with the crop and delivers a wide range of ecosystem services including weed suppression as well as pollen and nectar for bees, pest predators and butterflies While the benefit for pest control on dairy farms is unclear its other attributes make trial plantings of A. inermis in future MxG stands a worthwhile addition to this research on the ecosystem services benefits of planting MxG shelterbelts on dairy farms.


Fig.9: Acaena inermis purpurea


Media opportunities

The lincoln-based team consider that a media release covering the key points of the work to date may be appropiate and we are contacting Steve Attwood at Westland Milk Products to explore this idea. Of course we will not pursue any media links without the invlovement and full approval from the company.

Project Update March 2013

Project Update – To March 10, 2013

MxG Plant Survival

With no rain at all recorded at Karetu farm last month, this season has proved to be difficult for establishing MxG plants in areas without irrigation.

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Figs. 1 and 2 below from Edwards Road paddock at Springston, where MxG plantings receive some irrigation, illustrate this. Fig. 1 is of the southern fence line, looking east, which only just picks up moisture from the centre pivot. The MxG plants in the row next to the fence receive no water and although they are still alive they are only 20 cm tall. Plant height increases further into the paddock as they start to pick up moisture from the irrigator.


Fig. 1; MxG plantings in Edwards Road paddock along the fence line not reached by the irrigator.


Fig. 2.; MxG plantings in the Edwards Road Paddock looking north down the irrigated fence line.

The plants in the adjacent corner which receive a regular water supply from the centre pivot, as shown in fig. 2, are thriving and many of these are now a metre tall. It will be interesting to see how all MxG plants in this paddock develop and whether the drought-affected plants ever achieve a worthwhile dry matter yield over the next two seasons.

MxG Production and Habitat Creation

At Aylesbury farm, fig. 3, where MxG plants suffered initially when irrigation was not available, the plants are now thriving and are over a metre tall. Irrigation from the Centre pivot started on December 21, 2012 and the plants have achieved this height in just two months. Figs. 2 and 3 also illustrate the new habitat that these plantings have created on what was previously a prairie type landscape. MxG has a vigorous growth habit and thus there is possibly a reduced need for blanket weed control where it is planted. This will be tested by comparing the growth of MxG plants in sprayed and unsprayed areas to establish whether blanket weed removal improves MxG plant growth. As the MxG plant matures light, to the under-story canopy will be reduced in the centre of the plantings, possibly reducing plant diversity. However, MxG above-ground growth is largely absent in the spring and this may allow a diverse plant community to establish within the plantings earlier in the year. One benefit of this will be greater food availability for pollinators. Other ecosytem service benefits related to habitat creation of the plantings being monitored are improved nesting sites for bumble bees and resting areas for skinks. Although these environmental improvements may not impact directly on farm profits, they do send a signal to national and international markets that New Zealand dairy farms aspire to higher levels of functional diversity. The shelter effect on pasture growth is also, of course, important.


Fig. 3; MxG plantings under the centre pivot in paddock 22 at Aylesbury farm. Bumble bee motels have been positioned here to assess if these plantings improve the occupancy rates of these motels on dairy farms. This will aid pollination success in nearby seed and other crops.


Fig. 4; Edge of MxG planting adjacent to paddock 22, Aylesbury Farm, where shelter effect will be measured.

Collection of data

Collection of early baseline data to be used in assessing improvements in pasture production where MxG shelter is established has been taking place. This has involved recording soil nutrient levels, water application rates, soil moisture levels, pasture and MxG production, nutrient and water stress levels. Recording of pasture production from the paddocks where MxG is planted, using the C-dax pasture meter supplied by Agresearch, enables yield maps to be created, as illustrated by the attached file, paddock 21, which is of the pasture heights from paddock 21 at Aylesbury Farm on February 8, 2012. Using this technique will enable a spatial record of pasture growth over time to be created and this will be invaluable in assessing changes due to shelter effect.

This week soil analysis will begin to provide base values to find if there is a shelter effect over the next three years on soil nutrient levels. The following technique will be used:

Study Area

Paddocks have been planted in their north western corner with MxG creating three sampling areas. 1) Where the MxG plants are growing. 2) The area of the paddock immediately influenced by the shelter effect from the MxG. 3) A control area where there is no shelter effect and which is of the same size as 2).

Soil Sampling

Soil sampling will be carried out in each paddock planted with MxG over the next two weeks to get a base value for each area and will be repeated at the same time of year over the next two years. Fifteen cores will be taken along the sampling diagonal coming out from the shelter and these will be homogenised. This will be repeated at an equivalent location in the control area. One sample from this mix will then be sent to Hill Laboratories for analysis.One sample will be kept for in house analysis. This will be repeated for the control area and also 15 cores will be taken from where the MxG is growing.

Soil samples sent to Hill will be fresh soil and will be analysed for the following; pH, CEC, calcium, magnesium, Olsen P, potassium, sulphate sulphur, volume weight.

Soil samples to be analysed in-house will be air-dried at 30 degrees centigrade and stored for analysis later. Drying will continue until the soil weight has stabilised. These will be analysed for total carbon and total nitrogen using a CNS analyser.


Thank you to everyone helping me to continue this research, in particular Chris Pullen, Westland Milk Products, for the continued funding and support, Samuel Dennis and his team at Agresearch for allowing me to use their equipment and for assisting in collation of data and creation of yield maps, Mark Williams and his staff at Aylesbury farm for their help and co-operation and Dave Irvine and Marv Pangborne for letting me use their farms.

Project Update February 2013

February Update

This month has seen a continuation of last month’s dry and hot weather causing very dry conditions. This is being reflected in the occurrence of two severe bush fires near two of the farms where Miscanthus giganteus (MxG) has been planted. Fortunately at Aylesbury farm where all MxG plantings are irrigated this hot weather has produced ideal growing conditions.

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MxG is a warm season perennial grass that is a useful cellulosic bio energy crop due to its high yield potential. It is a C4 grass, as is maize , which means it is a very efficient user of water and grows better in warmer conditions. This has enabled it to survive at Karetu farm in the absence of irrigation and where the soil is poor. Lack of water at Karetu has started to cause visible stress in some of the weaker plants but this will become less of an issue as the plants develop and send down their deep tap root.

Reseach indicates that Miscanthus has a very low nutrient removal rate compared to other potential bioenergy crops. The plant reportably has a remarkable ability to turn only modest amounts of nutrients into large amounts of biomass. Testing of this during this research will include monitoring soil nutrient levels and MxG dry matter yields over the next three years. Of interest is that some MxG plantings, those on Karetu farm, will receive no additional nutrients and additional water supply whereas plants on Aylesbury farm will, due to being planted within the milking platform, receive nutrients supplied to the pasture. This is not deliberate but will be due to some fertiliser spread on the pasture reaching the MxG plots.

One of the potential benefits of MxG on dairy farms is that it is multi-functional. As well as generating ecosystem services through its role of providing shelter, which are being measured as part of this research, it can be used to produce silage, if cut early, or material similar to straw when harvested when mature. Nutrient analysis of plant material is at present being undertaken by Miscanthus New Zealand. The plant is certainly palatable as inadvertently tested when cows broke through fencing on Aylesbury farm when power to the fence was lost! A back- up system is now available to reduce the risk of this. Research indicates that regrowth from grazing is rapid providing the growing point is not damaged through trampling. This was certainly the case in this instance as the following pictures illustrate.


Fig 1 Heavy grazing of MxG plants removed above ground vegetation

Progress to date


Fig 2 Plants had a well developed root system facilitating rapid regrowth

Monitoring of soil moisture levels, water input and pasture production is now well underway. This has been possible due to the excellent co-operation and assistance from Samuel Dennis and his team at Agresearch. C-dax pasture meter readings are being used to monitor pasture growth. At present the aim is to monitor the control areas and eventual sheltered areas to try and ensure these areas are as similar as possible before the shelter effect develops next season. Whole pasture records are also recorded to provide furher information for this research and for Agresearch’s work on yield analysis.

Pot trials are now mature enough to enable testing of equipment to monitor expected shelter effects on plant transpiration and photosynthesis rates. Steven Stillwell and I will be testing equipment over the coming weeks.

Monitoring of bumble bee motels placed in six MxG paddocks has revealed that out of 48 motels placed with 4 compartments in each motel only one compartment showed any sign of occupancy. This is in line with expectations due to motels being placed towards the end of the bee nesting season and also bumble bees tend to crawl through patches of long grass when searching for nesting places. These are in short supply on intensive dairy farms and is one reason why plantings of MxG may lead to a higher occupancy rate of these motels in the future.


Fig 3 MxG two weeks after grazing

Project Update January 2013

January Update

There are now three dairy farms planted with Miscanthus giganteus (MxG) with a total of 10 paddocks being used to firstly investigate the growth potential of the plant itself and also to monitor its effectiveness in providing ecosystem services to dairy farms. There may also be potential to plant further paddocks next season.

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Planting has now been completed on all farms with mixed success. MxG plants on Aylesbury Farm needed a lot of emergency watering to keep them alive. Ground conditions were dry at planting with soil moisture falling to 9% and no significant rain has fallen since the 28 mm downpour on Friday 7th December. Fortunately K-Lines were put in place and the MxG areas were irrigated with 24 to 40 mm of water. The Center Pivot came on line just before Christmas and we now have a very good set up for trials work.The plants are now responding well to the increased water availability.

Planting at Karetu has also been very successful. There was more moisture in the soil at planting time, 15%, and on Friday 7th, two days after planting, there was 35 mm of rain fall.

The area of planting is beyond the edge of the Centre Pivot and soil moisture level will now have fallen to 8% as illustrated by grass in front of the MxG dying off.

The MxG however is still green and average height at one month of age, 16 cm, is higher than the 12 cm for plants on Aylesbury Farm at a similar age.


MxG plant in paddock 13 Aylesbury Farm now growing well under irrigation.


Karetu Farm. Edge of pivot irrigation at the back of paddock 15. MxG planted along top left fence line.

The soil here is also very poor and Poplar trees that the MxG replaced struggled to grow. This shows the MxG’s robustness especially if it eventually yields well in such a harsh location.


Karetu Farm. MxG plant growing at the back of paddock 15.


MxG planted in very stony soil on Karetu farm.

Final plantings of four paddocks, three into already dry soil, have suffered due to no rain post planting and very high temperatures. There may have also been some residual chemical present as Gorse in this area was sprayed six days prior to planting. Some plants are still green but the majority have died back except for the one paddock that receives water from the Centre Pivot. Over time the plants may recover or alternatively the area will be re-planted early next year.

t appears that MXG is very robust providing intial soil moisture levels are high enough to allow it to establish itself in the very early stages. If it dries out initialy as on Aylesbury farm it is difficult to sustain. However once established it copes well with harsh conditions as on Karetu farm. On irrigated dairy farms in Canterbury planting well into January is suitable but for unirrigated areas successful planting beyond November becomes very weather dependent.

Future Work

Measurements in the immediate future will be concentrating on grass production in the area influenced by the MXG plantings and also a similar control area in the same paddock not influenced by the MxG.

It ls hoped that over the time of this research protection of grass and clover plants by the MxG shelter will be reflected in improved grass growth and water use effeciency. Water appliction rate and soil moisture levels will also be monitored in the same areas.The Bumble bee motels placed in six paddocks will be checked for occupancy later in the summer. As the MxG matures we may find occupancy rate of motels within the MxG shelter increases over the next two years.

Winter work will involve setting up weather recording equipment, analysing collected data, soil sampling including obtaining a base value for earthworm populations and reviewing existing research. We will look at whether we need to install lysimeters to fully understand how the MxG is affecting water use efficiency and will look at whether we can set up a system of using eddy covariance to monitor gas emisions from sheltered paddocks.

Next summer the detailed effects of MxG on the micro climate of the sheltered area of paddocks will be monitored in detail together with measurements of the shelter effect on photosynthesis and transpiration. To ensure equipment being used is able to record the data required plot trials are being set up this summer on the Lincoln University Nursery Unit to test these in controlled conditions.


Finally many thanks again to my three farmers Mark Williams, Marvin Pangborn and Dave Irvine for letting me continue to use their farms for this research and for the help I have received and to Agresearch for letting me use their C-dax pasture meter which I am now in a position to utilise.

Project Update December 2012

December Update

Planting of Miscanthus giganteus (MxG) in the first four paddocks took place on the 13th and 14th of November at Aylesbury Road farm. The existing grass was first sprayed with Roundup and then left for two weeks before being cultivated the day before planting.Thank you Mark for organising this and to those who carried out the work. Also thanks to all my farms for giving me the chance to test the potential of what hopefully will prove to be a very interesting plant.

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Plants have now been in the ground for three weeks and are beginning to strengthen and produce vibrant shoots. Those plants that have developed the most are already illustrating the impressive growth rate that, if they grow to their potential, will enable them to reach a height of 3 metres next year and four metres in subsequent years.



Planting has not however been without its problems. Firstly the machine planter we used did not plant the MxG plant plugs deep enough. Immediately after planting there was a good downpour of rain and subsequent inspection of the MxG plants showed many of the plugs had become too exposed. Most plants were subsequently planted deeper which was important as the surface soil dried very quickly but moisture remained at a depth of 10cm plus.



The weather has been very dry since planting with only one significant rainfall event two weeks after the initial rain following planting. Most days have also had persistent drying winds which incidentally the MxG shelterbelt will hopefully eventually protect the pasture plants from. Providing sufficient water has been a problem but to date survival rate is good, 80 – 90 % in most paddocks. The plants that are starting to get away do have a robust look about them. Once plants get their root network established the plants should be fairly resilient.

Planting has also started on Karetu farm and should be completed tomorrow.Thank you Marv for organising the contractors to get the areas cultivated. Conditions here are harsher than at Aylesbury Road. One paddock should receive some water from the irrigator but the other paddock is part of the dry block. All plants have been hand planted to ensure they are placed at sufficient depth. This is feasible due to the relatively small area being planted. Also all plants were well watered for several days prior to planting. Some plants can be drip irrigated but initially they will be left to see how they cope with the conditions unaided. However if the dry weather continues for some time some means of watering the plants may be needed.

The last four paddocks to be planted will be sprayed this week and cultivated and planted next week. This will be on one of Dave Irvine’s farms. I am very grateful to Dave for taking the time out of his very busy shedule to show me round the farm. Firstly because his operational manager was away at the time and so he did not have any free time and secondly because I needed a second visit to re-orientate myself as to where we had been the first time.

By the time of my next report I will know how well all plantings have established themselves and work can then begin on starting to monitor the ecosystem service benefits generated by Miscanthus plantings.

The plants that have already established themselves are growing well at present.

Project Update November 2012

November Update

My research proposal has been approved subject to two adjustments. One of these was to narrow the scope of the research, as it was felt that too broad an area was being considered and the other was that I needed more paddocks planted with Miscanthus to provide a robust trial that would give statistically valid data.

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To address the points raised we have decided initially to concentrate on the eco-system service benefits generated from creating Miscanthus shelterbelts. I am in discussion with Pete Morrison and David Irvine about planting Miscanthus on their farms and I should hopefully have ten paddocks from which I can collect data. Areas to be researched are production and water use effeciency from shelterbelts; the effects of shelter on earthworm abundance, mineralisation rates and selected bio-diversity indicators; and the growth characteristics of Miscanthus including its carbon sequestation rate, feed value and yield potential.

I will also be planting quadrats of clover in some of the Misacanthus paddocks next year to assess whether clover persistency and pollination rate is improved in the presence of shelter.

Progress to date

Ground preparation has started on Aylesbury Road farm and Karetu farm. Miscanthus plants have been ordered for delivery on November 14th and a machine planter has been sourced for planting. Karetu is to be planted at the end of November.

Paddocks on Rivergold Dairies Farm, owned by David Irvine, will be looked at this week for suitable planting locations for Miscanthus.

Forty eight bumble bee motels have been placed on Karetu and Aylesbury Road farms. In each Miscanthus paddock eight motels have been placed, four in the unsheltered control area and four in the location of the Miscanthus plantings. Occupancy rate is not expected to be very high this year but over the next three years occupancy rate should indicate whether there is a preference for motels placed in the Miscanthus shelterbelts.The motels are being used to assess the role of Miscanthus in improving biodiversity on dairy farms and also as part of the research into pollination of clover plants.

Monitoring equipment at present is being sourced so that I can measure the effects of shelter on the microclimate in the paddock. Daily readings over the summer months will give detailed information on changes occurring in one paddock on Aylesbury Road farm. This plus the remote sensing of the soil water profile already in place on the farm will be useful data in determining the effects of shelter on pasture growth and water use efficiency.