Sulzeiche, Natural monument in Walddorfhäslach, Germany.

The Sulzeiche is a pedunculate oak (Quercus robur) about 450 years old, growing on the Schaichberg ridge at roughly 440 m. Its trunk has a circumference of 6.35 m, and its multi-branched crown spans more than 25 m at its widest. A large main branch broke off long ago, and moisture entering the wound has caused rot in the sapwood.

The tree originated several centuries ago and thus stands for a long natural history of the region. In the 18th century, people used this place for prayers, showing how significant this spot was already back then.

The oak is linked to theologian Friedrich Christoph Oetinger, pastor in Walddorf from 1746 to 1752, who is said to have prayed here and preached to the spirits. Otto Michel, founder of the Tübingen Institutum Judaicum, called the spot a place where heaven and earth touch.

The site sits on the eastern edge of a larger protected area established in 1981 and is easily accessible on foot. Visiting is free, and the spot works well year-round, though it is best during warmer months when nature is most active.

The nature reserve around the oak, established on 16 November 1981, protects a forest-edge biotope with open soil and poor grassland. Its speciality is the digger wasp Didineis lunicornis, rare in Central Europe, which few visitors ever notice.