Usually mold or wood rot is easily recognizable by the telltale dark soggy patches that form around the door frame.
Garage door frame rotted.
Some garage doors are.
These dark spots are caused by the growth of fungi as they feed on moist wood.
Wood garage doors tend to absorb all the water and start expanding.
Insert the tip of a flat crowbar under the trim.
To repair rotted door frame first remove rotted wood with a 5 in 1 or other sharp tool.
But there are several less obvious symptoms you should be on the lookout for such as.
Mix polyester wood filler or bondo wood filler and press it into the recess with a putty knife.
In case you have had a plumbing accident water in your garage will move to your garage door.
With time the wood frames and bottom starts rotting and breaking down.
The main cause of rotted garage doors is water damage.
Then coat the rotted door frame area with wood hardener as shown.
Pry on the crowbar to lift the trim and loosen it.