Blanket bogs are accumulations of partially decomposed vegetation that form extensive wetlands, usually in upland areas. Rainfall, rather than groundwater, is the major source of moisture. Compared with lowland raised bogs, the academic literature on upland blanket peats is thin and the first site studied with peats formed from the early Holocene (10,000 years ago) is Slieve Gallion. The deposits here have yielded a radiocarbon dated pollen record that demonstrates the sequence of plants from 10,000 years ago to recent times. It also allows direct comparisons to be made with contemporaneous lowland vegetation over the same period. Of particular interest was the discovery from the pollen record on Slieve Gallion of a dramatic general increase in alder woodland around 7,000 years ago.
Since the original research was conducted in the late 1960s and early 1970s, the area has changed considerably. Increased sheep stocking levels have led to intensive grazing and increased erosional damage but uncontrolled use of the area by mountain bikers is a recent alarming development.
Blanket bogs are fragile environments and this unique area is worthy of protection. It should be possible to develop a management plan limiting the grazing pressures and mountain bike access, particularly in the saddle area between the two summits which was the only area to yield the oldest peats.