Mr Goff pointed to Labour's plans to ensure the survival of rail in the region as an example of the party's commitment to Northland, but said the Auckland rail link, rather than the highway, was the priority.
Questions were also raised about a proposed "resource rental charge" for large-scale water users.
Under Labour's policy, regional councils would be responsible for allocating water rights under a user-pays system, which the party said would help fund new irrigation schemes and the cleaning up of polluted waterways.
One farmer told Mr Goff he would have to pay $234,000 per year in water charges - more than the net surplus of his business - if the plan went ahead.
Several others questions focused on Labour's plans to bring agriculture into the Emissions Trading Scheme in 2013, which Federated Farmers has previously railed against.
Mr Goff stood by the policies, saying taxpayers should not be saddled with costs while farmers profited.
"It is a user-pays approach, I make no apology for that," Mr Goff said.
"Whether it's an industrial plant or an agricultural plant, if there's a resource that's being used for your benefit and for your commercial viability and profit, then the first place we should look to pay for it is the person that's using it."
While the farmers were clearly frustrated, the questioning was not nasty, and one farmer made light of the situation, thanking Mr Goff for stepping into the "lions' den".
Speaking to media later, Mr Goff said the reaction was not unexpected.
"Federated Farmers is not known as a hot bed of left-wing radicalism," Mr Goff said.
