week 4
Continuing on from the previous week, the class went out to Hoffmaster State Park to do some surveying of dune #8. Each group was already defined in the last week when we learned about the surveying techniques, so we split into the groups and headed for the big blowout in the middle of dune #8
Dune 8
A blowout on a dune is a depression that forms by wind erosion or by a vegetation disturbance in the area. The dune can recover from a blowout by stabilizing the vegetation growth.
Dune 8 is a parabolic dune, this means that the shape of the dune is like a parabola. It forms by the sand moving inward but the vegetation keeps the arms of the dune in place to form the U shape.
Dune 8 is a parabolic dune, this means that the shape of the dune is like a parabola. It forms by the sand moving inward but the vegetation keeps the arms of the dune in place to form the U shape.
This dune was by far the largest dune we have surveyed so far. We had climbed up so far that I thought that I could reach up and touch the sky. It was like climbing a mountain, the dune was practically straight up the whole way and incredibly hard to climb.
Vegetation surveying
My group was in charge of surveying the dune for different types of vegetation. We would look for early colonizers such as American Beach Grass or Beach Pea. The other type of vegetation that we found were early succession plants like common juniper or wormwood.
I was in charge of creating the boundary that we would be observing the vegetation in. We used three different types of flags for this, the red flags were for the boundary, the orange flags set the center of the area, and the yellow flags located all of the Pitcher's Thistles that we found on the dune.
I was in charge of creating the boundary that we would be observing the vegetation in. We used three different types of flags for this, the red flags were for the boundary, the orange flags set the center of the area, and the yellow flags located all of the Pitcher's Thistles that we found on the dune.
The vegetation is important to surveying a dune. The roots help keep the sand in place to stabilize the dune. The different types of vegetation can also tell us whether the dune is very active or not. If there is more bare sand or early colonizers then the dune is fairly active but if there are more early succession or forest plants then the dune is rather stable.