The lake is fed by two small streams and by run-off water. Lakes such as this, with a small volume and a slow flushing action, are extremely sensitive to environmental pollutants. This black spruce bog is different in origin from the one seen earlier, beside the stream. This bog is completely enclosed by rock ridges. Water accumulates in this depression in the bedrock because it cannot drain away.
Evaporation is minimal because the water is held within the spongy sphagnum moss covering the bog.
A very moist habitat is thus created on what would otherwise be dry rock. You are now on top of a granite ridge which the trail follows to the parking lot. Here the environment is dry because water drains away quickly. Ridges such as this are usually dominated by jack pine, one of the few tree species that can grow under these austere conditions. This small drainage basin is very similar to others in the park.