An Etymological Dictionary of the German Language/Storren
Storren, m., ‘stump of a tree,’ from the equiv. MidHG. storre, OHG. storro, m., which is connected with OHG. storrên, MidHG. storren, ‘to stand out, project’ (Goth. andstaúrran, ‘to grumble, murmur’; root star, see starr. To this is allied störrig, adv., ‘stubbornly, obstinately,’ ModHG. only; lit. ‘clod-like, of the nature of a clod.’