Helichrysum trilineatum leaves

The simple, stem-clasping leaves of Helichrysum trilineatum are oblong or linear, the bases sometimes wider; anything but in picture. The margins are entire, and the tips pointed, notched or ending abruptly in a short, sharp protrusion or mucro. The leaf tips usually curve down and the lateral margins curve in slightly.

There are usually three longitudinal vein lines (sometimes grooves), visible on the lower surfaces of the leaves, more so when the indumentum is meagre or absent. The lower surfaces are sometimes white-woolly, grey from dense hairs to woolly, or green and hairless. The upper leaf surfaces may be finely covered in glands and also hairless or, in stark and surprising contrast, cobwebby or greyish-white woolly. 

The leaf dimensions are from 3 mm to 25 mm long and from 1 mm to 5 mm wide (iNaturalist; JSTOR; https://keys.lucidcentral.org).