The site forms a gentle south facing slope, falling from 80 m to about 60 m above sea level. As a result, drainage is from north to south. The moor falls into the catchment of the Silver Burn, which flows to the south of the site. Seepage of groundwater from the north and west, combined with flow from several springs, feeds the bog formed in a shallow basin at the south end of the reserve. The major soil type is a peaty podzol, freely drained beneath an iron pan. In the southern part of the site, the soils are freely drained iron podzols formed from fluvio-glacial sands and gravel.