In the past, I posted a picture of the Oregon Dunes (as seen from a distance. Those dunes started when perhaps well meaning people started planting grasses along the beaches to prevent the eroded beach sand from going too far inland. Sadly, the erosion covered the grasses, which grew back up through the sand and caught more sand and grew up even more. We saw places where one could see a good part of a pine tree with sand up the trunk. Last we heard, they are now trying to encourage people (think groups like scouts, church groups, etc.) to go out and dig out the grasses.
Here is a closer look at some of the dunes.
Here is a closer look at some of the dunes.