Reporter Rachel Dubrovin explains why it's so easy for these fires to get started, and how they can be prevented.
"I heard this crackling noise and I look over to my right and the entire tree was just up in flames," said WSU Student Allison Montgomery. "It was just orange."
Montgomery said she was on her way to class when she noticed a fire outside a house on Valley Road at about 11:00 Thursday morning.
"First thing I do, you know, call 911," said Montgomery. "Make sure they're aware of it."
"We were actually headed to Starbucks to go get coffee, saw the smoke" said WSU Student Victoria Aydelotte.
KLEW News was one of the first on the scene. We watched as Victoria Aydelotte showed up, grabbed a shovel, and sprung into action.
"I looked around, didn't see water available so I grabbed something metal and I'm trying to put out the fires to keep them from spreading to the other property since it was a couple feet away," said Aydelotte.
"I was 100 percent panicked," said Pullman Resident Mark Eastman. "I was running here and there, spraying water, trying to keep the hose from kinking."
As it turns out, it all started thanks to this white, fluffy cottonwood pollen. Mark Eastman said he accidentally started the fire when ashes from his cigar ignited a pile of it in his backyard.
"Thought I had it contained, but I wasn't quick enough, and it started spreading out in all directions," said Eastman.
Luckily, firefighters were able to extinguish the flames within a matter of minutes, with minimal damage to the house. But they said it's a problem they see every year, and residents need to be extra careful while this while stuff is still floating in the air.
"That stuff is extremely flammable," said Pullman Fire Prevention Officer Rich Dragoo. "What we have a lot of the time, you just toss a little cigarette butt in there and that'll ignite that stuff and away it goes."
Dragoo said you can prevent fires like this by cleaning up your yard.
"The easiest thing to do with that is to get your hose out and wet it all down," said Dragoo. "Once it gets wetted down and matted down, then you can go in with a rake and rake it all up."
Witnesses we spoke with said these trees are clearly hazardous, and they hope the rest of the community takes caution.
"Be very careful with the open flames you have," said Aydelotte.
"It's so dry, it's like tinder," said Montgomery. "It's igniting fluid. Anything that could spark it will just make it go."
Luckily Cottonwood pollen fires haven't caused any injuries or a significant amount of property damage in Pullman so far this year, but Fire Prevention Officer Rich Dragoo said if you don't take care of the hazard, a small Cottonwood fire could quickly become a large house fire.