3rd October 2023

Longer residual control of broadleaf weeds from CALLISTO® herbicide provided Phil Wheaton, of Streaky Bay, in South Australia, with valuable time in the early part of the season. 

Mr Wheaton runs a cropping and livestock operation on the Eyre Peninsula with wheat, barley and oats grown in rotation with the pasture country. 

Shearing is timed for the weeks just after planting, which can often take a week or two out of the calendar and limit the time available for post-emergent spray applications. 

“CALLISTO® buys us that time,” Mr Wheaton said.  “Some years we don’t have to put a post-emergent on.  If we can get good weed control through to canopy closure, any weeds that germinate are usually stunted and aren’t normally setting viable seed, [often] we can go the whole season without that extra spray.” 

In cases where a post-emergent application is necessary, Ester 680 or MCPA LVE are used prior to stem elongation. 

CALLISTO® herbicide is used in one third, to a half of the program, every year to control broadleaf weeds, particularly wild turnip and wild radish among his Brassicaceae weeds. 

A pre-emergent mix of herbicides includes CALLISTO herbicide for broadleaf control, Avadex* and Treflan* primarily for grass weeds and glyphosate as a knockdown and to assist with tank mix compatibility. 

Mr Wheaton said CALLISTO® herbicide was particularly good on wild turnip among other Brassicaceae weeds. In the interests of resistance management and robust weed control, he’s assessing management options including WeedSeeker*. 

“We know we have sulfonylurea (SU) resistance in Lincoln weed (Diplotaxis tenuifolia) and challenges with other weeds,” he said. 

To maximise the weed control of CALLISTO® herbicide, he uses the top label rate of 200 mL/ha and a water rate of 90 L/ha to make sure there is good coverage. 

“With CALLISTO®, the full label rate buys us time by allowing the herbicide to work longer through the season.  We still get 80 hectares out of a tank, with coarse to very coarse nozzles used to reduce drift. 

Seed is planted into 225mm row spacings at a speed of nine kilometres per hour so there is minimal soil throw onto the sowing rows. 

The enterprise was traditionally barley focused but has moved across to wheat in more recent years. 

Pasture paddocks are rotated through to cropping with spray topping before wheat on wheat or barley and then wheat. 

West Coast Ag agronomist Clint McEvoy said they had been using CALLISTO® since 2021 with clients including Mr Wheaton. 

“In that first year we had a late start and there was a lot of weed pressure and more to come,” he said. 

“We initially went in at 100 mL/ha but since that time have increased the rate to 150 mL/ha to buy our farmers a bit more time,” he said. 

“The higher rate keeps them out of the paddock and with many being mixed cropping farmers it is very handy.” 

“We’ve found it performs well across many of the weeds we have here and mixes with BOXER GOLD®, and other herbicides.” 

He said there was also Group 2 (formerly B) resistance in the area, so another mode of action was handy. 

CALLISTO® herbicide controls a wide range of broadleaf weeds and the label has recently expanded from wheat and barley to now include oats and triticale. 

Herbicide resistance is a major problem for many broadacre growers with known resistance to herbicide Groups 2 (B), 3 (D), 4 (I), 5 (C) and 12 (F), in broadleaf weeds such as Indian hedge mustard, wild radish, wild turnip, capeweed, fleabane, prickly lettuce and sow thistle. 

As CALLISTO® herbicide is a Group 27 (formerly H) herbicide it has the ability to control resistant weed species and set the crop up for an excellent start to the season. 

Pre-emergent applications via IBS can be applied at between 100 and 200 mL/ha with the higher rate recommended in areas of increased weed pressure or when longer residual activity is required. 

A split application option has also been added to the label where growers can apply 130 mL/ha pre-plant, followed by 70 mL/ha post plant, pre-emergent to improve in furrow weed control over IBS applications alone. 

* Registered trademarks. 

®Registered trademark of a Syngenta Group Company. 

The information provided in this article is intended as a guide only. Information contained in this article has been provided by the manufacturer. You should not rely on the information in this article, and it should not be considered advice. You should seek professional advice regarding relevant factors specific to your situation. This article does not take into account variable conditions that may impact performance. Always read and follow label directions before using any product in this article. To the maximum extent permitted by law, Nutrien Ag Solutions Limited and its related associated entities will not be liable for any loss or damage suffered by any person arising out of any reliance on any information contained in this article.