Growers have so far this year largely escaped the regulatory net cast by Hawke's Bay Regional Council, a net designed to lower urban air pollution levels in winter.
Winter is when air pollution levels soar on still nights in Napier and Hastings, due to domestic fires.
Last year Hawke's Bay Regional Council chairman Rex Graham called for stronger regulation around orchard burn-offs, but his own council says the timing of air-quality exceedances shows domestic fires are the problem.
This year, of the 28 fines for fires issued by the council were nearly all were in urban areas.
Council Regulation Group Manager Liz Lambert said the $300 fines were typically issued to "mums and dads" burning rubbish in their garden.
She said possibly all of the 28 fines issued this year for excessive smoke – officials were unsure about one – were issued in the council's air zone one, which comprises the suburbs of Napier and Hastings.
Urban residents have spent millions of dollars upgrading wood burners to comply with rules aimed at lowering smoke levels, but growers in air zone two, surrounding Napier and Hastings, can still burn fires over the winter months.
"Our focus is on the urban areas – air zone one – and that is where most of the population lives and where the worst effects of the smoke are felt," Lambert said.
"And it's also the area that is actually covered by the National Environment Standard."
"Those areas that are outside that are larger than 2 hectares and are actually not covered by any rules in the National Environment Standard, so we've created rules in recognition of the unique physical circumstances here on the Heretaunga Plains.
Growers can't burn prunings until September unless they are controlling disease or are undertaking development, when they can burn entire trees if they follow the council's smoke-management rules.
"We like to think they are common sense ones around the type of material that can be burned and also around being observant of weather conditions – making sure the wind is blowing in a certain direction etc and not too strong," Lambert said.
She said if people witnessed a fire spreading smoke towards an urban area they should ring the council's 24-hour pollution hotline on 0800 108838.
Hawke's Bay Fruitgrowers Association president Lesley Wilson said disease was an issue and machines were being developed to make chipping trees more practicable.