Fire Ecology and Management of Grassy and Heath Balds

Balds are treeless shrub or grass-dominated ridges and peaks that occur at middle to high elevations in exposed locations. There are two principal types: heath balds and grassy balds. While heath balds are dominated by a heavy cover of ericaceous shrubs, grassy balds are dominated by grasses and sedges, though scattered shrubs may be present.

The origin and maintenance of bald communities, particularly grassy balds, are not fully understood. Hypotheses regarding grassy bald formation include human origin in the historic period, geologic origins, climatic events in relation to topographic position, disturbances including wind and ice storms, insect outbreaks, chronic grazing (by now extinct native grazers), and fire.  The origins of balds may be unclear, but grazing by domesticated animals most likely maintained balds in the form that we know them, while in the recent past fires were not important in their maintenance.  The origin of heath balds is also unclear, but is thought to be related to site conditions: heath balds can form and persist in exposed, infertile landscapes that are not hospitable for trees.  

While very little research has been done on fire effects in balds, prescribed fire is sometimes used in grassy bald and grassy bald-like communities to maintain vegetation structure and to maintain habitat for animals that utilize such areas.  For example, prescribed fires are used to maintain open habitats where spruce-fir forests once stood in an effort to provide habitat for Golden Eagles. While there is some debate about whether use of fire as a force to maintain true grassy balds is appropriate, in the absence of grazing, prescribed fire has become a useful management tool for public land managers to discourage encroachment of woody plants into these bald communities.