Description from Flora of China
Alyssum incanum Linnaeus, Sp. Pl. 2: 650. 1753; Farsetia incana (Linnaeus) R. Brown.
Herbs annual or biennial, (20-)30-80(-110) cm tall, densely pubescent with appressed stellate trichomes mixed with some simple ones. Stems erect, simple or few basally, often branched above. Basal leaves petiolate, oblanceolate, (2.5-)3.5-8(-10) cm, withered by flowering time, base cuneate or attenuate, margin entire or repand, apex obtuse. Middle and upper cauline leaves sessile, margin entire, apex acute or obtuse. Fruiting pedicels slender, erect to erect-ascending, (4-)5-9(-12) mm. Sepals erect-ascending, 2-2.5 mm. Petals white, narrowly obcordate, (4-)5-6.5(-8) mm; lobes oblong, (1-)1.5-3 × 0.5-1.5 mm, apex obtuse. Filaments white; median pairs 2-3.3 mm, flattened base appendaged or unappendaged; lateral pair shorter, with an appendage 0.3-1 mm; anthers oblong, 0.5-1 mm. Fruit oblong or elliptic, slightly inflated, (4-)5-8.5(-10) × (2-)2.5-4 mm; valves stellate, obtuse at both ends; style slender, 1-4 mm, basally sparsely pubescent. Seeds lenticular or ovate-orbicular, 1-2.3 mm in diam., slightly flattened, narrowly margined. Fl. May-Aug, fr. Jun-Sep. 2n = 16.
Mountain slopes, foothills, fields, river banks, roadsides, disturbed sites, meadows, pastures; 700-1900 m. Gansu, Liaoning, Nei Mongol, Xinjiang [Kazakhstan, Kyrgyzstan, Russia, Tajikistan, Uzbekistan; Europe; naturalized in North America].