NASA likes to start their trends in 1979, during the second coolest January-July on record in the US. They have determined that CO2 emissions are making the fire sason longer.
Study: Fire seasons getting longer, more frequent – Climate Change: Vital Signs of the Planet
Like in early May, 1884. When there were massive forest fires burning in the Midwest and eastern US.
03 May 1884, 1 – The Boston Globe at Newspapers.com
Or in April, 1889 when there were forest fires burning all over Wisconsin.
25 Apr 1889, Page 6 – The Lawrence Gazette at Newspapers.com
Or in April 1880 in New Jersey.
15 Apr 1880, 5 – The Rutland Weekly Herald and Globe at Newspapers.com
Or in 1881 in New Jersey.