The US Fire Administration last posted reports for FEMA were 2009. They list a total of 78,792 fires in the US with a total of 5,921,786 acres burned. 2006 was an even bigger year with 96,385 fires totaling 9,873,745 acres burned. We're not talking house fires, car fires, etc. These are wildfires, brush fires, forest fires etc.

Compared to NYS average of burned acres to total numbers of fires, the national average for 2009 is 75.15 acres burned. The average in 2006 was 102.44 burned acres per fire.. A 50 acre wild fire may seem small, till the acres turn out to be yours or a place you value. Though NYS may indeed average only 50 acres per event, the Overlook Fire burned 2800 acres of the Shawangunk ridge.

The US Fire Admin periodically releases Topical Papers on various fire related topics. The one pertaining to wildfires was for years leading up to 1998. A bit dated, but the figures could prove relevant to this discussion. Natural fires made up less than 5% of all fires, compared to "incendiary or suspicious" fires which made up just shy of 40% of the reported fires for the period.

www.usfa.fema.gov/statistics/estimates/wildfire.shtm

www.usfa.fema.gov/downloads/pdf/statistics/v2i19-508.pdf

http://www.dec.ny.gov/lands/42378.html