KAHULUI » The state’s last remaining sugar company has been researching alternatives to burning leaves off its sugar cane crop before harvest.

But Hawaiian Commercial & Sugar Co. said it hasn’t found an alternative yet, The Maui News reported. For now the company needs to continue burning cane to stay in business, it said.

"We do care about what happens in the community, and we’re working very hard to mitigate and minimize the impacts we have on the community, whether from smoke or whatever else," HC&S General Manager Rick Volner said at an open-house meeting this week.

More than 100 residents and company employees attended the three-hour meeting Tuesday at Maui Waena Inter­me­diate School.

Burning cane can cause plumes of smoke to drift downwind, blanketing cars and sidewalks with black ash.

Some residents believe the smoke contributes to a flare-up of asthma and other acute respiratory diseases, especially in young children.

One resident asked why HC&S does not practice an alternative method known as mechanical green harvesting, which would not require cane burning.

Volner said the company has tried the method. It purchased two "top-of-the-line" John Deere harvesters several years ago to collect sugar cane without burning, but the sloped terrain and rocks characteristic of HC&S fields have resulted in "significantly reduced yield" of sugar cane crop, making it not "economically viable," he said.

The company, which owns 36,000 acres on Maui, burns an average of 400 acres per week during its nine-month burn season. The season began March 13.

Experts have tried for years to determine whether cane burning on Maui has led to an increase in respiratory illnesses, though the prevalence of volcanic smog, or "vog," rainy weather and other factors have made it nearly impossible.