By far the two most-widely spoken West Frisian dialects are Clay Frisian () and Wood Frisian (). Both these names are derived from the Frisian landscape. In the western and north-western parts of the province, the region where Clay Frisian is spoken, the soil is made up of thick marine clay, hence the name. While in the Clay Frisian-speaking area ditches are used to separate the pastures, in the eastern part of the province, where the soil is sandy, and water sinks away much faster, rows of trees are used to that purpose. The natural landscape in which Wâldfrysk exists mirrors The Weald and North Weald areas of south-eastern England – the Germanic words "wald" and "weald" are cognate, as is the more generic "wood".