(Reuters) - President Donald Trump early on Saturday said "gross mismanagement of forests" is to blame for two unchecked wildfires burning in California, where nine people have been killed and hundreds of thousands forced to evacuate.

"There is no reason for these massive, deadly and costly forest fires in California except that forest management is so poor," he wrote in a Twitter post.

"Billions of dollars are given each year, with so many lives lost, all because of gross mismanagement of the forests. Remedy now, or no more Fed payments!," he added.

(Reporting by Brendan O'Brien in Milwaukee; Editing by Kirsten Donovan)