Cleavers kill March-May
Cleavers kill March-May
By Andrew Swallow
GROWERS can now use a single product to target cleavers in winter wheat and barley from March to May, including in T1 tank-mixes, without any compromise of control, says Dow AgroSciences.
Its new product Starane XL is a blend of 2.5g/litre of florasulam (as in Boxer) and 100g/litre fluroxypyr (as in Starane). That combination gives a wide window of 95%-plus control, says regional manager Stuart Jackson.
"From the first of March to GS39 it offers cleavers control irrespective of temperature and how slow or fast the cleavers are growing."
That 95% control level is needed to prevent yield loss and minimise seed return. Work at IACR-Rothamsted shows one cleavers plant/sq m causes an average 3% yield loss in winter wheat. If you can find the weed a spray will pay, he says.
The florasulam component is key with early treatments. For cleavers affected by autumn treatments or hardened by frost, 1.8 litres/ha of Starane XL is recommended, delivering the equivalent of 150ml/ha of Boxer.
But for cleavers showing clear signs of growing 1.25 litres/ha is adequate, provided the weed is less than 20cm across. However, early timings can miss spring germinating cleavers, notes Mr Jackson.
At later timings the fluroxypyr component takes cleavers down quickly regardless of size, provided soil temperatures are 5C and rising. Speed of action becomes critical beyond GS32, because that is when competition effects start to rob yield.
Wide tank-mix compatibility, including up to four-way tank-mixes with fungicides, pgrs, trace elements and other herbicides, should reduce the need for specific spray passes through the crop to control cleavers.
"The T1 fungicide timing often falls between the optimum control timing for Boxer and Starane 2," says Mr Jackson.
Unlike straight Starane, the XL formulation can be mixed with Opus (epoxiconazole).
As florasulam is an ALS-inhibitor it is subject to restrictions on tank-mixing or sequencing with other ALS-inhibitor products such as Lexus (flupyrsulfuron-methyl) or metsulfuron-methyl (Ally). It cannot be used on the same crop as certain ALS-inhibitors, such as Eagle (amidosulfuron) or Monitor (sulfosulfuron).
Starane XL also controls mayweeds up to rosette stage and all brassica weeds up to four true leaves at the 1.25 litres/ha rate, and up to flower buds visible for both weeds at the 1.8 litres/ha rate.
Pack-size will be 5 litres and price about £15.40/litre on farm, says Dows James Knight. With Boxer costing about £17/ha at 100ml/ha and Starane 2 about £23/ha at 1 litre/ha that is cheaper than tank-mixing, he notes. *
Special mixes
The XL formulation will be widely available, plus Starane Gold and Starane Vantage, containing only 1g/litre of florasulam, through specific distributors only. "These cannot be used for the early control slot unless you add more Boxer. The 1g/litre of florasulam gives these products robustness when used mid-season – it is doing much the same job as adding HBN to straight Starane at this timing," says Mr Knight.
• Boxer plus Starane formulation.
• Wider control window.
• More tank-mix opportunity.
• No timing/control compromise