Deersum official Frisian name is Dearsum; it is a village in Boarnsterhim, Fryslân, formerly in the former municipality of Rauwerderhem. The village is on the main road from Leeuwarden to Sneek, and along the old Middelzeedijk (the dike along the old Middelzee, aka Borndiep, from which the new municipality got its name). Dearsum is well known for its cattle-breeding, and the speed-skating champion: Ids Postma. Dearsum:
coat of arms: in red three silver cloverleaves, placed 2, 1; The coat of arms is on the weathervane of the church. The colors are derived from the former municipality of Rauwerderhem. Flag: two vertical stripes of red and white, proportioned 2:1; in the red stripe a white cloverleaf. (clover is the symbol of cattle-breeding). Source: Genealogysk Jierboekje 1986. Encyclopedie van Friesland, 1958. Jarig Bakker, 19 Aug 2003