Femeiche, Natural monument oak tree in Raesfeld, Germany.

Femeiche is an ancient oak in Raesfeld standing about eleven meters tall with a crown spread of eight meters. The trunk measures about twelve meters in circumference and is supported by wooden posts since part of it is hollow.

The oak is estimated at 600 to 850 years old, though some estimates reach 1,500 years. Courts of the Feme were documented beneath it until the 16th century, making it Central Europe's oldest known court tree. It was first protected around 1900 and named a National Heritage Tree in 2021.

The name Femeiche derives from the Feme, the medieval secret courts of Westphalia; the tree was earlier called Rabenseiche or Erler Eiche. Documented Feme court sessions were held beneath it until the 16th century, and it is regarded as the oldest and best-known court tree in Central Europe.

The oak stands southwest of Erle's centre, next to the old rectory, the village's oldest house, on the B224 three kilometres southeast of Raesfeld. The hollow trunk is held together by wooden poles resting partly on stone slabs, and a low slatted fence rings the base; the tree is viewed from outside the fence. The site lies at about 60 metres above sea level in the Hohe Mark-Westmünsterland nature park.

The trunk is now only a shell of sapwood with cambium, bast and bark; the heartwood is gone. In 1989 its girth at one metre was twelve metres, and intact it would have measured about fourteen, making it the thickest oak in Germany. The crown is held up by wooden poles resting partly on stone slabs.