Farmers across the country are being warned not to buy potentially useless bales of rape straw treated with an active ingredient banned for use near livestock.

Due to the shortage of cereal straw this year, some growers are baling rape straw instead of chopping it.

However, the National Farmers’ Union is warning stockkeepers to make sure they know what they are buying as many of the bales will be unable to be used.

If ASTROKerb was used on the crop as a herbicide on rape in the autumn or winter, the straw cannot be used as animal bedding.

ASTROKerb contains highly effective active ingredients propyzamide and aminopyralid. However, it is the addition of aminopyralid which is the issue as it has been shown to be very persistent.

Growers may also be aware of the product Forefront T, which is a herbicide used on grassland.

This also contains aminopyralid, and there have been failures in the following crops when muck from livestock feeding on grassland treated with Forefront T has been spread in the next season.

Warnings from the ASTROKerb label

The product label warns that ASTROKerb must not be used on land where vegetation will be cut for animal feed, fodder or bedding nor for composting or mulching within one calendar year of treatment.

Following crops (winter and spring wheat) should not be planted within 30 weeks of application of ASTROKerb.

Therefore following good agricultural practice ensure that all remains of the oilseed rape crop have completely decayed before planting susceptible crops.

The full AstroKerb label can be found here.

This would also apply to Ralos – a less widely used herbicide which contains metazachlor, aminopyralid and picloram.

Alternatives for next season

The good news is that alternatives are already past the development stage. Belkar is a new post-emergence autumn-applied herbicide for use on winter oilseed rape and is expected to soon be on the market in the UK.

Belkar can control a wide range of broad-leaved weeds, including Cranesbill, Cleavers, Poppy, Shepherd’s Purse and Fumitory and with a wide window of application, it also allows the crop to establish.

It contains Arylex and picloram as active ingredients so there will be no straw restrictions if this is used.

A full launch of Belkar is planned in 2019; however, in the meantime, a small quantity will be available to farmers this year through Corteva Agriscience distribution channels.