Fires can do this?
That's exactly what I thought, too. To honest, when I first arrived in Florida, the types of fuels (plants) were different enough to the type of firefighting I was accustomed to doing, I thought the same thing about a lot of the green forested areas, too...until I saw them burn.
The one under the lake went into a pete bed and kept burning beneath the lake (just outside Gainseville), then came up on the other side and took off.
The trees there looked green, but were dry and brittle. We had to raise our drop height in large tankers from 200' to 300' and in some cases 400', because the weight of the retardant was topping the trees; it was breaking off the trees, sending them to the forest floor, and increasing the fire, in some cases.
Another problem we enountered there was palmetto, which is rich enough in pitch that it burns very hot, is hard to extinguish, and is very nearly explosive in an active fire.
Another problem which those on the ground had to face, but I didn't...was aligators. When I lived in Oz I became facinated with crocs and thus became a little familiar, but it's not something I've ever had to deal with during an active wildfire. I spent six years on the ground as a firefighter on top of a number of years in aerial fire now...but never saw an aligator. We had reports in areas were dropping about crews that were stuck because of aligators in the way. I thought that was interesting.
What was most striking about working down there, however, was just how different the nature of the job could be. One becomes accustomed to doing the job a certain way, and then moving to a very different climate with different weather patterns, winds, and fuels, and one has to adjust to an entirely different way of approching the fire. Including ones that burn under a lake.