Herbage glabrous or minutely hispidulous, stipitate-glandular. Leaf blades oblong-obovate, 10–25 mm, margins serrate to lobed (teeth or lobes in 3–5 even pairs, spinulose-aristate). Involucres 5–7 × 4–5 mm. Phyllary apices greenish, spinulose-aristate, densely and promently gland-dotted, glands often coalesced as small resin pockets. Florets 10–13; corollas 4–5 mm. Cypsela ribs not forming apical horns.
Phenology: Flowering Aug–Oct.
Habitat: Low hills, alkaline and subsaline plains, alkali marshes, stream benches, grasslands, fencelines
Elevation: 0–20(–50) m
Of conservation concern.
Isocoma arguta is known only from Contra Costa and Solano counties.