Ash's lark is typically 14 centimetres (5.5 in) in length. It has greyish-brown upperparts with paler edging to its mantle feathers, a buff-coloured underbelly and underparts with brownish streaks, a paler belly and vent, a light crest, and buff eyebrow stripes.
Such a description is insufficient, however, since as with some other lark species it is difficult to definitively describe the bird without comparison to its close relatives. In the case of Ash's lark, it is smaller than the rufous-naped lark or the red-winged lark, and more greyish and marked on its mantle than either the singing lark (which has a thicker bill) or the pink-breasted lark (which has a pinkish breast).
Its songs have yet to be identified.
The only place known to be home to Ash's lark is a small area just north of Uarsciek in south-eastern Somalia, about 80 kilometres (50 mi) north of Mogadishu. Even here where it is locally common, however, Ash's lark is easily overlooked because it shares the area with nine other species of lark, including both the red-winged lark and Somali long-billed lark. It is possible that Ash's lark is also present along the coast somewhat to the north of its known range since much of this land is little explored by ornithologists.
At present, little is known of Ash's lark's ecological relationships.