This spot is a Vernal Pool. Vernal pools, also known as ephemeral pools, or vernal ponds. During almost every year, vernal pools experience flooding/ filling and receding of water. The flooding or filling happens in the winter and spring, when winter showers and snowmelt fill up the pools. It stays wet until late summer, when most start to dry up and are dry for all of fall and some of summer, and some are dry for all of summer. Most are dry for some of the year, but some pools stay partially wet over the course of one year, even more, but no matter what, all vernal pools dry up periodically. An important part of the dry season in vernal pools is the flowering of the native plants, which attracts pollinators such as bees, butterflies, and flies. Some wetlands teeming with this life can not be identified as a vernal pool. This is because some states identify vernal pools as NOT having a water source such as a spring or river. Some wetlands have a source of water, and hence are not identified as vernal pools. Also, when completely devoid of water, the ground in a vernal pool will become grey after rain, telling it apart from normal ground, and there may be a depression where the vernal pool is.
Vernal pools are called so because they are often, but not always, the deepest in the spring ( vernal meaning spring). Vernal pools like this one, in the forest, are rarer, and are more associated with rocky basins and grasslands. Prarie pools are normally much bigger, but still have unique life and dry and wet spells. One this big are rarer, and we are lucky that it is here.
1) Here in the North east, at the end of the last ice age the glaciers started retreating. As the glaciers retreated, they left large chunks of ice buried in the ground. As these large chunks of ice melted, they left a depression in the ground called a kettle hole. When most of the ice melted, the sand, gravel, or dirt on top of the depression caved in, and the water, being less dense than the material, made its way upward, and formed a vernal pool. 2)Another way vernal pools can form is when the glaciers were either coming down, or retreating up to the north, the ice scoured the ground beneath it. When the ice retreated, the depressions left by the ice would fill up with rainwater. Another way that vernal pools can form is in river floodplains. As the river floods, the flowing water leaves depressions that would not otherwise form. As the river slowly returned to normal, water from the river would get caught in the depression. 3)Also, another way they could form, again with rivers, is that flowing sediment could pile up, forming a large, thick sandbar that the water from the river can not get through. As the sandbar widens and thickens, a pool of water can get trapped behind the sandbar, and as the sandbar continues to grow, gets cut off from the river’s current, making the pool be able to support the life listed below. 4)One other way that vernal pools can form, but is not a obvious, is that human activities can create habitats for vernal pools to form. Activities such as quarries, man made ponds, and detention basins can all support vernal pool species.
Even though that they are dry a lot, vernal pools teem with life when they are filled. More obvious inhabitants of the vernal pool during the wet phase are the breeding frogs and toads. Some species of salamanders, such as the Yellow Spotted Salamander, the Four-Toed Salamander, and the Red-Backed Salamander inhabit the vernal pools for breeding, however adults may only visit the pools briefly. Some indicators of a vernal pool in New England are Fairy shrimp, Wood Frogs, Spadefoot Toads, and some species of Mole Salamanders.
Vernal pools can form anywhere that there is a depression ( dent) in the ground. It doesn't matter about the bedrock, or soil types for a vernal pool to form. Some vernal pools develop hydric soil in flood areas, including organic matter, but it does not happen in drier areas. In some cases, the retention of water is caused by a hard layer at the bottom of the vernal pool.
Take a look around the area. What do you see? By the way, the soil is a bit sandy in this area. It is a fabulous spot to just relax. It is so peaceful. If you see any trash around the pool, please stop it from going into the pool. It could seriously mess up the vernal pool.
The requirements to log this cache are as follows:
1.) How can a hard bottom for a vernal pool be formed in a sandy environment?
2.) How do you think this vernal pool was formed? Why?
3.) How can a dry vernal pool be identified?
4.) Some wetlands can be identified as not a vernal pool. How is this possible?
5.) Include a picture of you and your GPS at the vernal pool with your log (optional)
That's it. While you are here, I recomend finding my night cache after finding this, so you can familiarize yourself with the area before you try to find the cache at night. Good luck!