Here is some background on prescribed burning. Prior to European settlement, the southwest Michigan landscape burned possibly as frequently as every three to five years due to fires started by lightning strikes and anthropological sources. Native Americans started landscape fires for a variety of reasons.
Generally-speaking, many of our native plants have evolved to handle fire and fire is actually beneficial for their growth cycle. Many non-native plants are not adapted to fire. So, prescribed burning promotes our natives and sets back non-natives.
There are different types of natural fires. The huge all consuming fires with 100 feet tall flames are called crown fires or catastrophic fires. The prescribed burns that are performed in Michigan are more typically crawling or surface fires, where the vegetation and/or leaf litter burns at the ground level. Careful understanding of the amount of fuel present and the behavior of fire given the temperature, wind, and relative humidity conditions helps burn bosses (technical term for person with lots of burning experience) keep the fire under control.
That said, sometimes unexpected things do occasionally catch fire, when you are burning acres upon acres. Yesterday, a half decayed, half still living White Birch tree caught on fire. I noticed the tree from about 250 feet away and, after walking over, took this video.
Birch Bark is oily (and, incidentally, an effective material to start a campfire), so having burned around numerous Birch trees, I am surprised that this does not happen more often.
The burn crew typically is in constant communication with radios. At the tail end of the video, some one radios instructions for Scott, a co-worker.
Other things I saw out in the woods were gigantic ant hills, easily measuring 10 feet plus diameter at the base and numerous crayfish burrows along the river and swampy areas. Word is that Eastern Massasauga Rattlesnakes overwinter in the crayfish burrows. The burn yesterday was patchy but good.