Calls for a complete ban on herbicide-tolerant swedes follow confirmation that hundreds of cows died last year after eating toxic varieties of the southern staple.
Not only does the Green Party want a ban on herbicide-tolerant plants, it also wants compensation for stressed-out farmers.
DairyNZ analysed 150 swede samples across three varieties and found varieties that can tolerate herbicides had toxic concentrations of a naturally occurring bitter chemical, especially when in flower.
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