Hunt Hill is located in Northwest WI, in an area that was affected by the glaciers during the last ice age. This is a reason that the bog could form here, and it took a very long time.
Why are bogs common in the Northwoods?
Bogs generally form in kettle lakes, or depressions left by glaciers in the last ice age, which was about 10,000 years ago. The depressions are formed when the glacier leaves a huge ice block behind as it retreats. The ice is then covered up sand, gravel and other debris. After the ice melts, a depression, also called a kettle, is left in the hole. These kettles often remain filled with water, never having an inlet or outlet for the water to flow. This bog does have an inlet and outlet, making it an atypical bog.
How does a kettle form into a bog?
Bogs develop gradually, exhibiting several levels/layers of growth along the shore. The first layer to develop in the bog is a layer of sedges. This is the thinnest layer and forms when the individual sedges form an interlocking mat with their roots. This layer grows very slowly (about 1 inch a year). New growth, such as sphagnum moss begins growing on top of the mat. (The mat is made up of millions of tiny plantlets!) When enough growth has occurred on top of the mat, the mat begins to move towards the middle of the lake and also begins to sink, eventually ending up on the bottom of the lake. As more plants grow, the old ones die and turn into peat because they cannot break down and decay in the bog. Peat is the compressed remains of dead plant materials. The plants don’t break down due to lack of oxygen, lack of bacteria, high acidity and low temperatures. Because of these unique conditions that create a ‘biological desert,’ there are plants that have specialized to live here, in particular, insectivorous plants, including the pitcher plant and the sundew. They supplement the nutrients the bog lacks with those from insects that they lure into their traps.
Once the mat has sunk to the bottom, trees can begin to grow in the bog because it is more stable and able to support them. The mat will continue to grow until the middle is completely filled in. (The layers of moss peat can be very thick – up to 40 ft – and is a vital element of the bog system.) This means when you walk on a bog, you are not walking on the ground, but instead on a layer of living and dead plant materials that are floating/in the lake. The trail looks ‘dirty’ but when you pick some of the ‘dirt’ up, you will see that it’s not dirt at all, but instead dead plants.
A few interesting facts about bogs:
- A bog is an early stage in the formation of coal deposits.
- After drying, peat can be used as fuel.
- Native American tribes used sphagnum moss as diapers.
- In WWII, sphagnum moss was used in place of surgical cotton; moss absorbs 3 times as fast as cotton and is naturally sterile due to acidity and absence of bacteria in a bog.
- Bog is a British and Irish slang word for toilet. Toilet paper is called a bog roll.
- Tannins (bitter taste in plants), given off from plant matter give tan color to bog water.
- Because the mass of peat is higher than the ground water table, moisture is provided almost entirely by precipitation and this is called ombrotrophic (cloud-fed). That’s why water is acidic and has low nutrients.
LOGGING THIS CACHE
In order to log this cache, you must do/answer the following questions in an email to the cache owner:
- What is the pH of this bog? Is it what you expected? Why or why not? What might have affected the acidity?
- What is the temperature of the water? How would a bog affect this? ** You will need your own equipment to determine the pH and temperature.
- What makes a bog different from a swamp?
- Please take a picture of you with your GPS at this location (optional).
