The Living Dune: Mt. Baldy

 

 Sand dunes are the most unstable landforms on earth; they undergo constant change from forces such as wind, water, and gravity. Not every dune changes so quickly, once covered in grasses, shrubs or trees, they become more stable, but the ones called "living dunes" change constantly, and relatively quickly. 

 Mt. Baldy is an example of a living dune right here in the Indiana Dunes National Park. Formed of sands from the Lake Michigan shore, by wind, this dune is "walking" inland at quite a fast pace of and estimated four feet per year. Here, against the bright blue sky and the snow, the sands stand out. Warmed by the sun, the snow melts relatively quickly at the top of the dune, and some of the snow is also covered by sand blown from the windward side of the dune. There's a distinct snow line across the top, where the wind has prevented the snow from sticking, and the sun has warmed things up.

   

 At such a rate of movement, the Indiana Dunes National Park is experiencing an unusual situation. The dune has already claimed part of the woods, and has now moved onto the parking lot road, blocking it.

In the not so distant past, there was a flat, grassy area to the right of the road, and just behind the camera, were several parking spaces. They are now all buried under the dune, not to be exposed for a few hundred years. This is also the dune where a young boy was walking in a roped off area and he fell into a sinkhole, burying him for hours. Luckily, he survived. It turns out that the void in the sand under the surface was caused by an ancient buried tree that eventually rotted, then the sand finally caved in as he walked over the exact spot. The dune was closed after this incident for about two years, then opened once again but only for ranger guided tours a few times a year.

   

 It's unfortunate the public is not allowed to explore the top of this dune as we once were prior to the cave-in, it had one of the most panoramic views of Lake Michigan and the surrounding countryside. Perhaps the park service will eventually find a way to mark the safe areas and once again allow people to walk in designated area. It seems people can't explore the namesake of the park at all. 

 To get an idea of how much this dune has moved, here is a composite of images I've taken over the years, showing the exact same spot of the dune. You can see the two individual trees get into deeper and deeper sand until you can no longer see them. The broken, dead branches behind the evergreen in the photo above, are the remnants of the trees pictured below.