Fast-tracking adaptation of grain production systems to climate change – Benchmarking Horsham East and Sheep Hills farmer groups. J G Nuttall, D R Price & A J Wallace Department of Primary Industries – Horsham September 2009 Acknowledgements This benchmarking review was funded by the Department of Primary Industries, through the project ‘Fast-tracking the adaptation of the grains industry to a changing climate’ (CMI 102686). The cooperation of 51 farming families within the study regions of Horsham East and Sheep Hills, who had active participation in the benchmark survey, is also greatly appreciated. Thanks also to Geoff Stratford (DPI) for valuable editorial comment. Agency personnel associated with the broader Department of Primary Industries project, ‘Fast-tracking the adaptation of the grains industry to a changing climate’ and the design and implementation of the benchmark survey were: Roger Armstrong (FFSR Horsham) James Nuttall (FFSR Horsham) De-Anne Price (FSV Horsham) Chris Sounness (FSV Horsham) Ashley Wallace (FSV Horsham) September 2009 Use of data and disclaimer No part of this publication may be reproduced without the prior consent of the author. While the information contained within this report is believed to be true and correct the Victorian Department of Primary Industries and its employees associated with this report give no warranty on quality of data and accept no responsibility for any errors contained herein and any damages or loss caused, suffered by any individual or corporation. 2 Executive Summary Across south-eastern Australia persistently dry seasonal conditions over the past decade has caused crop yield to be suppressed and have limited the diversity of crops grown where cereal production has been favoured over pulse and oilseed options. Two farmer groups, at Horsham East (central Wimmera) and Sheep Hills (northern Wimmera) are engaged in a participatory action research (PAR) program with the Victorian Department of Primary Industries with the aim of fast-tracking the adaptation of their farm enterprise to an uncertain climate, through identifying robust farming practices. In benchmarking the farming enterprises of these groups, both ABS statistics and a grower survey with 51 participants, were used. Vertosol soils dominated 80% and 50% of average farm area in Horsham East and Sheep Hills respectively. This soil type has high clay content and water holding characteristics; however under low rainfall conditions, little moisture is available to crops due to high matric attraction of water to clays. Average wheat yields in 1995 and 2008 were 3.3 and 1.7 t/ha respectively for the Horsham East district and 3.0 and 1.3 t/ha across these time periods for the Sheep Hills region. In 1995, the rainfall use efficiency (RUE) of 9.4 kg/ha.mm was similar to that of 9.0 kg/ha.mm recorded in 2008 for Horsham East. Average RUE for Sheep Hills was 8.7 and 8.5 kg/ha.mm in 1995 and 2008, respectively. Barley crops at Horsham East, on average, yielded 3.3 t/ha in 1995 and 1.8 t/ha in 2008 whereas in Sheep Hills average yields were 2.9 and 1.5 t/ha in 1995 and 2008 respectively. The average RUE at both locations was higher in 2008 (drier) compared with 1995 where at Horsham East this ratio increased from 9.4 to 9.6 kg/ha.mm and for Sheep Hills from 8.9 to 10.4 kg/ha.mm. Canola yield averages at Horsham East decreased from 1.9 to 0.7 t/ha and in Sheep Hills 1.5 to 0.3 t/ha between 1995 and 2008. The canola RUE for Horsham East averaged 5.0 kg/ha.mm in 1995, but decreased to 3.6 kg/ha.mm in 2008. For Sheep Hills, RUE was 4.1 and 2.3 kg/ha.mm for 1995 and 2008 respectively. Highest RUE was 7.9 kg/ha.mm, this occurring during both 1995 and 2008 seasons. 3 Lentil yields in 1995, on average, were 1.8 and 1.1 t/ha for Horsham East and Sheep Hills respectively, however in 2008 average yields dropped to 0.6 and 0.3 t/ha for Horsham East and Sheep Hills, respectively. Lentil RUE dropped from 5.1 and 3.8 kg/ha.mm for Horsham East and Sheep Hills respectively in 1995 to 3.3 and 1.7 kg/ha.mm in 2008. Highest lentil RUE was 10.0 kg/ha.mm, this occurring in both regions. Chickpea, on average, yielded 1.2 and 1.6 t/ha for Horsham East and Sheep Hills respectively in 1995 but this declined to 0.5 and 0.3 t/ha respectively in 2008. The RUE of chickpea in 1995 was 3.8 and 4.8 kg/ha.mm for Horsham East and Sheep Hills respectively but dropped to 2.5 and 2.0 kg/ha.mm, in 2008. The highest chickpea RUE was 7.6 kg/ha.mm, this occurring at Sheep Hills in both 1995 and 2008. Maintaining standing stubble has increased over the period 1995 to 2008, although a high proportion of farmers grazed stubbles at Sheep Hills, whereas for Horsham East farmers increasingly avoided grazing stubbles. Incorporation of stubbles was not a common practice in the Horsham East district in either 1995 or 2008, whereas over 50% of farmers at Sheep Hills either incorporated some or all of their stubbles in 1995, although there has been a trend away from this practice up to the present time. The burning of at least some stubble was common practice in 1995 where 85% and 62% of growers burnt stubble in Horsham East and Sheep Hills districts, respectively. Between 1995 and the present (2008) there has been a shift away from burning stubble, with only 30% and 4% of farmers now burning stubbles in the Horsham East and Sheep Hills districts respectively. Fluid fertilisers were used by 29% and 27% of farmers at Horsham East and Sheep Hills respectively in 2008. Alternative fertilisers such as guano, duck manure, formic acid mixes and unspecified biological products were also used by 24% and 17% of farmers in the Horsham East and Sheep Hills region respectively in 2008. For phosphorous application a ‘standard rate’ was the most common method used in 1995 where 75% and 85% of farmers adopted this approach in Horsham East and Sheep Hills respectively. More recently (2008) there has been a shift away from this method, particularly in Sheep Hills, where now only 25% of farmers apply a ‘standard rate’. In this region, P application has been increasingly based on nutrient budgets and on seasonal conditions where 40% and 30% of farmers respectively now using these methods. For Horsham East, the rate of P application has also been increasingly based on seasonal conditions, where 25% of farmers used this approach in 1995 compared with 35% in 2008. Growers at Sheep Hills have increasingly used soil tests for decision making purposes on P nutrition. 4 For nitrogen (N) applications, 60% (Horsham East) and 78% (Sheep Hills) of growers applied a standard rate in 1995; however in 2008 these proportions had dropped to 35% and 38% for Horsham East and Sheep Hills respectively. Growers at Horsham East favour the method of basing N application on the seasonal conditions where in 2008, 80% of farmers used this method; compared to 35 % for their counterparts at Sheep Hills. Using soil tests to determine N requirement are used in part or full by 35% of farmers at Horsham East and 50% of farmers at Sheep Hills. No nitrogen is ever applied to 6% of farms at Horsham East, this pattern being constant over time (1995 & 2008). At Sheep Hills the proportion of farms where no N is applied has increased from 5% in 1995 to 25% in 2008. Adoption of technology such as steering guidance systems, inter-row sowing and variable rate technology varies considerably. At Horsham East, no growers used GPS guidance systems on an entire farm basis in 1995; however by 2008, 30% of farmers had taken up this technology. At Sheep Hills, 12% of growers used GPS guidance in 1995 and this has increased to 70% of growers in 2008. The high rate of adoption of guidance systems at Sheep Hills may be linked with the desire to inter-row sow, where 68% of farms sowed either some or all paddocks to this method in 2008. This is compared to 30% of farms at Horsham East being inter-row sown. For variable rate technology, only 1 grower at Sheep Hills utilizes this technology across the entire farm and 3 growers across both districts apply variable rate to a portion of their farms Over the last decade seasons have been dominated by below average rainfall. This raises the question, is growing successful crops during this period due to good luck or good management? Horsham East growers believed it was a combination of both factors, whereas at Sheep Hills, farmers were of the strong opinion that a good crop was delivered through good management. For the decade of dry seasonal conditions, growers across both regions were united in their opinion, that natural climatic variability was occurring and that the previous dry seasonal conditions were not related to human induced climate change. 5 Table of contents Background ………………………………………………………. 7 General …………………………………………………………… 11 Land use …………………………………………………………... 11 Rainfall ……………………………………………………………. 14 Soil type …………………………………………………………… 14 Crop type ………………………………………………………….. 16 Crop species ………………………………………………………. 16 Crop production and water use ……………………………………. 21 Stubble management ………………………………………………. 23 Fertiliser management ……………………………………………... 26 Adoption of technology …………………………………………… 28 Grower perception on cropping success and climate ………………. 31 References …………………………………………………………. 33 Appendix 1. ………………………………………………………... 34 6 Background In the last decade, persistently dry seasonal conditions across south-eastern Australia has increased the incidence of crop failure, suppressed yield and limited the diversity of crop choice within the farming system where grower sentiment has favoured cereal production over pulse and oilseed crop options.