An area more than half the size of Co Louth has been destroyed by wildfires since the start of the year.
The country's fire chiefs have revealed that burning vegetation and gorse and forest fires ruined 42,000 hectares or 420 square kilometres of land up until the end of April.
The Chief Fire Officers' Association (CFOA), which is staging a two-day annual conference in Cork, warned that fire services, particularly in western counties, have been stretched to the limit trying to contain blazes.
Seamus Murphy, chief fire officer in Mayo and CFOA chair, warned that starting fires is illegal for six months of the year.
"The starting of fires maliciously and deliberately by landowners to clear vegetation outside of the late February deadline is illegal and reckless as it not only puts life and property at risk and causes immense damage to wildlife and the environment, but it also diverts critical fire services resources away from responding to other emergency incidents," he said.
"While the weather at present is not conducive to large forest, bog and gorse fires, we would like to remind landowners that it is an offence under the Wildlife Act to burn growing vegetation between March 1 and August 31 in any year, on any land not then cultivated. The sad fact is that if this simple rule was adhered to, many costly and dangerous wildfires would be avoided."
In one incident alone during the Easter bank holiday weekend 2,800 hectares of land were destroyed by fire at Ballcroy in Co Mayo.
Elsewhere, figures show that fire service units in Munster were called out to deal with 491 separate forest and gorse fires during the first four months of the year.
Agriculture Minister Simon Coveney and county councils in Kerry, Mayo and Donegal have repeatedly warned about the dangers of starting fires outside of the legal burn period.
Other issues for discussion at the conference include learning from New York's emergency response to superstorm Sandy and the evolving role of social media in major emergency management.