After two dry seasons a wet winter has brought Tasmanian growers back to the old challenges of waterlogging and finding crops able to cope
AG (Askin) (left) and Will Morrison inspecting a waterlogged, but coping, wheat crop in July.
PHOTO: Brad Collis
Will Morrison spent more time than usual this winter looking out onto his paddocks rather than working in them. A 200-millimetre downpour at the start of June led to widespread flooding, idle machinery and the loss of an ambitious faba bean crop.
Growers: Will, AG (Askin) and Ian Morrison
Property: Pisa Estate
Location: Cressy, Tasmania
Farmed area: 2600 hectares
Average annual rainfall: historically 520mm but about 450mm in 2014 and 2015
Soil types: mostly duplex – shallow topsoil (10cm) over a gravelly clay
Soil pH: 4.3 to 5.5 (CaCl2)
Cropping program (2016): 600ha wheat (Manning, Trojan), 200ha malt barley (Westminster), 80ha canola (Clearfield® 971A), 300ha poppies, 100ha oaten hay, 50ha rye grass seed, 100ha clover seed, 200ha peas, 0ha faba beans
But it has done little to curb enthusiasm for his expanding cropping enterprise, which like most in Tasmania is more diverse than the typical mainland farm and which is also working through some fundamental changes – climate and market shifts providing plenty of scope for research and innovation.
Will, his brother AG (Askin) and father Ian run four farms as a single enterprise that includes wheat, barley, canola, poppies, peas, crossbred ewes, prime lambs and trade lambs, lucerne, beef cows and, potentially, faba beans.
Until the mid-1990s it was primarily a Merino medium wool business, but Will says cropping now generates 80 per cent of income. The Merinos have long gone.
It has been a steep learning curve to reach a position of now managing successfully a diverse grains program that comprises 600 hectares of wheat, 200ha of malt barley, 80ha of canola, 300ha of poppies and 200ha of peas.
Will attributes much of their accumulated knowledge and experience to the on-farm research undertaken by the GRDC-supported Southern Farming Systems (SFS) group.
He has been an enthusiastic host of SFS trials, which at the moment include faba beans and wide row canola – two developments showing particular promise.
Trials to date suggest faba beans could become a valuable break crop for the high-rainfall stubble-retained cereals system, which needs a reliable, resilient grains legume to break disease cycles and provide another weed-control strategy.
The first irrigated trials last year delivered up to 7.85 tonnes per hectare, which immediately flagged them as potential replacements for shrinking pea and poppy markets. Last year (2015) was a particularly dry season and growing conditions this year are at the opposite end of the weather spectrum, with large areas of Tasmania’s cropping landscape waterlogged.
For researchers it provides an ideal opportunity to test the crop under vastly different circumstances. SFS research and extension officer Georgina Moloney says the trial paddocks were looking a bit grim in July with the ground still very wet: “But people say faba beans are a crop that reward you if you treat them nicely. So we’re keeping a close eye on them and we’ll see how they recover.”
A little too late
Will Morrison is also keenly observing the trials because his own crop was lost: “We sowed too late. Two weeks earlier and they would have been out of the ground and able to cope,” he says.
“But we’ll try again next year because the yields look promising and we need something to replace falling demand for peas and poppy.”
Growers are also uncertain about long-term control of a systemic mildew that has afflicted poppies in recent years.
Will Morrison says the wet winter in 2016 came as a bit of a shock after two extremely dry seasons that stretched the state’s water reserves to the limit. However, he says they just managed to maintain their irrigation program and the two dry years were actually their most profitable to date.
“In a dry season, with irrigation, we are calling the shots … we are, in effect, controlling the weather. So we make more money in the dry years, but need wet years to refill the lakes so we have that irrigation control when it is needed.”
The Morrisons have 36 pivot irrigators installed over 1600ha, but have not yet invested in converting them to the variable-rate (VR) application systems now available. “We can operate a few of them from our smart phones,” Will says. “But we don’t yet have the variable-rate technology.
“We know VR irrigation and nutrient application would also allow us to better manage waterlogging spots and even out crop performance, but it’s a big investment.”
High cereal yields
Will says the biggest change for the business in recent years has been the increase in area sown to cereals. “We now have the knowledge to produce high yields, around 10t/ha, and this has led to a significant increase in cereals. The wheats are high-rainfall dual-purpose varieties, though we don’t graze them unless we have to. All of the harvest goes to the local feed market,” he says.
Will says the ideal start to sowing (wheat) is 25 April but the Tasmanian season is longer, with harvest usually not starting until mid-January. Nitrogen management has been simplified to a set rate of 100 kilograms per hectare in four applications between GS31 and GS39: “We don’t apply any urea upfront.”
Will says that in terms of profitability, wheat has now caught up to poppies, which traditionally were the mainstay of the cropping program, but are slipping under the pressure of a world oversupply: “The area we are contracted to grow has been halved and the prices are down too. So grains have caught up, and they are also less risky to grow.”
With grower confidence in wheat and barley high, the current R&D priority has been the faba beans and wide row canola.
“The trials moving canola rows from 30 centimetre (12 inch) to 76cm (30 inch) lifted yields from 4t/ha to 5t/ha, which is a big improvement. It seems the wider rows allow the plant to put out more tillers.”
As for growers elsewhere in the Australian grainbelt, deep-ripping is also making an appearance. Will says the soils in the region are mostly duplex – shallow topsoil over a gravelly clay that acts as a hardpan barrier.
“Last year we deep-ripped a canola paddock in an area that usually dries out because of the shallow topsoil. It yielded 3t/ha, making the deep-ripping very worthwhile despite the diesel burned. We only deep-rip down to about 30cm but it’s enough to break up the clay.”
The other practice change adopted from SFS research is controlled-traffic farming (CTF): “We have established a 24-metre system with an 8m air seeder and 24m spray rig, all on tramlines,” Will says.
“Unfortunately, CTF goes out the window when we grow peas because the pea harvesters go wherever they want, but we’re hoping the peas will eventually be replaced by faba beans.”
Resilience a bonus
Aside from their value as a profitable break crop, the faba beans also reflect the fact that, recent dry seasons aside, the usual cropping constraint is waterlogging. If faba beans prove to be as resilient as experience elsewhere suggests, the push will be on in earnest to find markets.
As an example of how climate variability changes people’s thinking, Will says they used to crop on raised beds as a matter of course, but 2014 and 2015 were so dry that maintaining the beds seemed unnecessary.
“But our dad now keeps telling us this year is a normal winter. So maybe losing the faba beans and not being able to get machinery into paddocks is back to reality.
“Maybe we need to write on the wall somewhere a reminder: ‘It can still get wet’.”
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