A large mulch pile ignited at Fruhling Sand and Topsoil at 1010 228th Street Southwest Sunday evening, where fire officials say it will continues to burn until it exhausts itself later this week.

The blaze was started after the pile was soaked, causing it to ignite. Similar to hay bails, when mulch becomes wet bacteria inside it begin multiplying and producing heat, which can become so great it catches fire.

According to Bothell fire officials, two Bothell firefighters and and engine will continue to monitor the blaze until it burns out, which could take days.

“Natural vegetation always does have that potential for combustion. Especially after it rains,” said Bothell Fire Department Spokeswoman Kirsten Clemons.

“We’re doing our best to decrease the smoke, and work towards ways to put the fire out,” she said.

The blaze started around 6:30 p.m. Sunday, and closed down a portion of 228th Street Southwest from 4th Avenue to 14th Avenue until 10 a.m. the next morning.

No injuries have been reported.

Fire officials said residents should store compost away from structures since combustion is always a possibility.