The money and legal cases had achieved little so far but Mr Spencer's hunger strike had prompted calls for a national review of land clearing laws and renewed lobbying for a Royal Commission into climate change science.

The Australian Farmers Fighting Fund, a pool of money established by the National Farmers Federation in the 1980s and controlled by a board of trustees, helped drive parts of Mr Spencer's long-running legal battles against the Commonwealth in his fight to get compensation for government land-clearing restrictions.

The NSW Farmers Association president, Charles Armstrong, this week said the legal efforts had "not achieved as much as we would have liked" but conceded more AFFF funds might be used for Mr Spencer's future legal battles.

"I can't pre-empt the trustees, though," Mr Armstrong said.

Despite Mr Armstrong and another source using the $100,000 figure, two other sources close to Mr Spencer said the amount was more like $20,000, suggesting the higher amount was spent on the Lower Murray groundwater case - Arnold and others versus the Commonwealth (the Spencer case was linked to this from a constitutional perspective).

Mr Spencer, "Saarahnlee", Shannons Flat, has been waiting on a decision by the High Court to see if he would receive "just terms" compensation for being unable to clear his land.

The High Court case was delayed until the outcome of the Arnold case was known. The AFFF would not confirm the exact amount it released for Mr Spencer's cases.

Mr Spencer's barrister, Peter King, worked pro bono and nobody could provide details of how much the court cases have cost Mr Spencer.

The disconnect between Mr Spencer's cause and the farmers associations could undermine the credibility efforts of both parties.

NSW Farmers has used his protest to campaign for a Royal Commission into the science behind climate change - a push perhaps more likely to succeed since climate change sceptic, Tony Abbott, became federal Opposition leader.

"Farmers should not be carrying the burden of Australia's carbon reduction ambitions," Mr Armstrong said.