Knoxville (WVLT) -- If you were wondering about the smoke over downtown Knoxville for part of the, we can tell you a mulch fire is to blame.
The fire broke out on Ailor Avenue, near Sutherland Avenue at just before 3:00 P.M.
For several hours, smoke and flames poured from Shamrock Organic's mulch storage facility.
Firefighters say internal moisture causes mulch fires, which is why mulch suppliers frequently turn their piles to try and dry them out.
"They do constantly turn the products," said Captain Darrell Whitaker from the Knoxville Fire Department, "but still moisture from the green material they put in there builds up, and it can certainly ignite, especially on a hot day like today."
By 7:00 P.M. most of the fire was out.
Trucks still remained at the sight to keep wind from spreading smoldering mulch outside the set up containment area.