Vegetation Community Monitoring at Hot Springs National Park
Hot Springs National Park has many forested hills and valleys. These woodlands provide important ecosystem services for the hot springs. They serve as a “recharge zone,” where surface water seeps into the water table. Healthy forests protect groundwater and springs from contaminated surface water. Logging and settlement preceded the National Park. Now, natural community management is a priority. Scientists measure the woodlands to learn about changes over time.
Scientists began measuring plants at Hot Springs National Park in 2007. Seven permanent locations are deployed to observe woodland plants over time. Scientists use these data to describe and detect changes in the forest.
The forests at Hot Springs National Park have a relatively closed canopy. Medium-sized trees dominate the overstory. Both tree density and basal area were greater in 2014 than 2007. Standing dead trees, called snags, are also important in woodlands. In 2007 snags made up approximately 8% of the basal area, compared to approximately 20% in 2014. Oaks, hickories, and pines are the most common trees. In 2014, scientists observed more slippery elm, hawthorn, Eastern redcedar, and red maple trees.
The understory was similar between 2007 and 2014. Woody plants dominate the understory. About 30% of herbaceous plants are common. Scientists obseved few invasive species in low numbers at the monitoring sites. Arkansas bedstraw, Siberian elm, honeysuckle, prickly lettuce, and Nandina are the only invasive plants found. These data help managers assess goals and develop future action plans for protecting the park’s woodlands.