In the southern part of Lammi the soil is mainly clayey. Relatively dry spruce- and pine forests with small raised bogs are typical ofthis area. The peatlands Few bogs are in their natural condition. The majority of them were dried 30-40 years ago. The distribution of the fields resembles that of the vegetational aeras.
Fields are most typical on the clay-dominated soils.
The Nort-East Lammi has poor soil and practically no fields.