Alongside presidential and congressional elections, voters in Sonoma County California will also have to decide if they are for or against Measure J, a controversial proposal which will outlaw large farms in the county.

Measure J is being proposed by animal rights activists in California who want to use the US Environmental Protection Agency rules on concentrated animal feeding operations (CAFO) to suppress large farms.

If passed, farmers in the county say that 24 farms will have to close, including six dairy farms, some of which are in organic production, but exceed the size threshold under the measure.

The state of California has already introduced Proposition 12, which controversially sets different rules on animal housing.

Farmers and politicians are worried that if the measure passes, it will be replicated elsewhere.