President Donald Trump lashed out at Democrat-governed California on Wednesday, warning its leaders to clean up forests that he said are full of dead trees posing a wildfire risk.

“California’s a mess,” Trump remarked at a Cabinet meeting after Agriculture Secretary Sonny Perdue said his department is “making forests work again.”

“It’a a disgraceful thing,” the president continued. “Old trees are sitting there rotting and dry and instead of cleaning them up, they don’t touch them, they leave them, and we end up with these massive fires.”

California has experienced 5,322 fires that burned about 621,000 acres so far this year, costing it $773 million for firefighting, according to the state. Fire is a perennial threat in the state, though it has experienced more than twice as much burned acreage so far this year than average.

Scientists believe climate change and rising temperatures are making California’s fires worse, but Trump blamed state leaders.

“I say to the governor or whoever is going to be the governor: you better get your act together,” he said. “They don’t want to clean up their forests because they have environmental problems cleaning it up — it should be the opposite, you’re going to lose your forest, you’re going to lose it.”

He threatened to cut off federal aid for firefighting in California, which he said costs “hundreds of billions of dollars” — an exaggeration. Total federal firefighting costs in 2017 were less than $3 billion, according to the National Interagency Fire Center.