Sulphur-yellow something. This is growing by the ruins of a 100-year-old cottage, and photographed mid-winter. Pruned constantly by cattle, hasn't been watered for decades (we have a mediterranean climate.) Fairly stiff branches. Arching growth to about 2.5m (8'). I think there is another about 20 miles away, growing on a low fence, and resisting attempts to strike it from cuttings. The colour varies a bit with the weather. I can't detect much scent, but it is winter. I assumed it was a Tea; but someone mentioned Solfaterre.