suitable for the formation of large underground passages, which are generally restricted to porous rock like limestone. Although lava tubes can form in certain igneous rock, they cannot appear in rhyolite, and the underlying basalt is both too deep and not formed in the proper volcanic conditions for tubes. The area is not known to contain any faults, and even if it did, it would not be permeable enough to drain half the river. Experiments conducted in late fall 2016 and announced by the Minnesota Department of Natural Resources (DNR) in February 2017, however, strongly indicated that the disappearing water simply flows back into the Brule River shortly below the falls. At the suggestion of state hydrologist Jeff Green, two DNR experts measured the water flow above the falls and several hundred feet (meters) below them. The two readings were virtually identical, suggesting no water was being lost to some other outlet. They accounted for the failure of visitors' floating objects to reemerge by explaining that the powerful currents in the kettle's plunge pool would be enough to hold down most material until it was pulverized. Green and a colleague planned to conduct a dye tracing experiment in the fall of 2017 when water flows dropped again, with the hope of determining where the underground channel rejoins the main river. They were discouraged from doing so, however, by park management, and they decided (under duress) that the dye experiment was not scientifically necessary to confirm that the water simply rejoins the river below the falls. Flora and fauna With an elevation change of , Judge C. R. Magney State Park supports a wide variety of flora and fauna. Overall, the park contains Laurentian Mixed Forest comprising both conifers and broadleafs. Before European settlement the Brule River Valley would have been forested mostly with white pine. Extensive logging and forest fires have altered the park's vegetation significantly, except around the rocky and inaccessible ridgetops. Today's secondary forest is dominated by aspen and birch, with stands of white spruce, sugar maple, and basswood. A few remnant stands of white pine have survived on hilltops and ravines, especially along Gauthier Creek. Large northern white cedars are abundant along the river. Inland are many dense stands of white spruce, the result of planting and vigorous natural reseeding after the timber harvests. Around the waterfalls, the constant mist creates a microclimate conducive to several plant