STOP 15: THE BARRENS’ PLANT COMMUNITY
Probably since the arrival of the first settlers from Europe, the frequently burned sandy soil region of northwest Wisconsin has been referred to as the “barrens.” Compared to the old growth forests that covered much of northern Wisconsin this area was usually considered quite sterile and was of little value to the timber barons of the nineteenth century. In actuality, thousands of years of sporadic fires created an extremely diverse mixture of grasses, forbs, shrubs, and trees. These plants are all well adapted to surviving fires or regenerating immediately after a fire. These species thrive in relatively sterile sand, love direct sunlight, and have adaptations that allow them to persist through frequent periods of drought that would kill off many other species.
Many of these plants have roots extending several feet into the sand to find moisture when lack of rain causes the shallower soils to dry out. Several species have seeds that can lie dormant for 40, 60, some times 100 years to survive prolonged drought or forested intervals between fires. Most are capable of sprouting from their roots after a fire burns off the above ground plant. All the species of plants in front of you demonstrate these survival tactics, but a cursory look at the tree species demonstrates a few of these traits.
The small oaks you see here could actually be centuries old. They readily burn and top kill during a fire, but their deep roots quickly sprout new stems that replace the burnt off stems. Jack pines have cones that remain closed until a hot fire causes them to burst open and shower the blackened ground with seeds. Red pines have thick bark that often protects them from fires that race along the ground. Aspen send numerous shoots up from one root mass after a fire, and shade out understory grasses and forbs preventing many fires from carrying through a stand of trees.
You may or may not be an expert when it comes to identifying plants, but please take a short walk out into the barrens and notice how diverse the area actually is. Also, think of the tough conditions these plants have adapted to over thousands of years of fire, drought, and sand. Currently, 246 species of plants have been identified on the Namekagon Barrens Wildlife Area (NBWA).