Tackling a persistent rye grass problem has required some out of the box thinking for one Central Tablelands cropping couple.
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Brett and Jasmine Ryan run adjoining farms, Rockvale and Arrowglen, totalling 400ha, plus another 300ha either share farmed or leased, all in the Barry district.
Their agronomist, Benjamin Romeo, of Summit Ag Canowindra, said areas such as Barry were productive country with an increasing area being turned over to dual-purpose cropping.
In terms of yields, in the past two years, the Ryan's farms have averaged 5 tonnes a hectare of wheat and this season (2020-21) have just harvested 2.7t/ha of canola (Hyola 970).
This past season's crop of Bennett and Accroc wheat, which is still being harvested has been averaging 7t/ha - including one 9ha block having yielded almost 12t/ha.
Mr Ryan, an ex-shearer, was using dual purpose wheat and canola varieties to take advantage of their longer growing seasons. They could be sown earlier, and therefore establish before winter, and be harvested later, hence avoiding the tableland's spring frosts.
Mr Romeo said they hadn't been able to get spring canola to work because it would flower in the frost window, however, the winter varieties have allowed them to get around this, with the past two year's winter canola crops averaging 2.5t/ha.
Ultimately what they're aiming for is to mimic the European concept of a 12-month crop, which kicks off with a November-December sowing.
So far they've only been able to push the concept as far as a February/March sowing, but this early sowing allows a window for establishment before winter sets in, the seedlings needing to be up and going in March to get their tap roots down.
This helps with three key aspects of the crop's development.
Firstly, so the plant gets established before the frosts hit; secondly so the crop has a head start come spring having already done some growing in autumn; and thirdly, to create some ground cover in early spring to provide competition for the rye grass.
Mr Romeo said Sakura, Boxer Gold and glyphosate were among the few available options that remained for ryegrass control, with the new options, Luximax and Overwatch, to be tried this year, too.
This was why they had opted for spring-sown chickpeas, the winter fallow allowing multiple knockdown sprays, plus Treflan, and Balance with Simazine, pre-emergents also used.
The preparation for chickpeas also includes a shallow rip and then a lime application at 2.5t/ha with a belt spreader, the lime being incorporated with discs (the soil pH is 4.6-5.3).
In seasons where it doesn't suit to plant chickpeas, buckwheat is also an option, Mr Romeo said.
The Ryans 2020-21 chickpea crop (which is expected to yield at least 2-2.5t/ha) was sown into a full soil profile at 90kg/ha with 100kg/ha of monoammonium phosphate on November 16 last year, after some storms.
This year they switched to Sima after using Hatrick for the previous two years.
They selected for good aschocyta tolerance, too, as Mr Romeo said the disease had made its way into the tablelands, the crop having had multiple sprays this summer.
"And that probably won't be the last," he said, while explaining the crop received 243 millimetres of rain from sowing to February 5.
On Boxing Day when the first fungicide was applied, the crop had not yet reached canopy closure, but they were aiming to layer the fungicide to protect later, new growth as it emerged.
The first treatment was with Select Xtra, Verdict and Mancozeb, while the second (in late January) was chlorothalonil and insecticide Trojan, added for heliothis.
Another chlorothalonil treatment was applied last week with more rain forecast.
The Trojan application was the first insecticide treatment and this would be followed with a softer residual to target the next wave of heliothis - a big challenge with a spring sowing due to its extended pod develoment window.
So far though, they had kept the heliothis at bay.
"If all goes well, we're looking to have these off by the end of March/early April and then we will turn around and sow a wheat crop directly behind it," Mr Romeo said.