Camassia quamash is a
perennial plant with a
herbaceous character that has a wide range of variation across its geographical range. It is a
monocot that has grasslike leaves, as typical of that group, that emerge from a persistent
bulb. The bulb is of moderate size, in diameter. The bulbs do not frequently cluster together and their surface is black while the interior is white with layers like that of an onion. The leaves very rarely number more than nine on a plant and range in length from . In comparison to their length they are quite narrow, 4 to 20 millimeters in width. The upper surface of the leaves may or may not have a pale, waxy coating depending on the variety. The flowering stems in wild or cultivated plants can be up to , but may be as short as . As the
inflorescence does not have branches it is a
raceme. The pale blue to deep blue
flowers appear in late spring to early summer (May to June in their native habitat). Each of the radially symmetrical, star-shaped flowers has six
tepals, about across, and six stamens. The leaves and bulbs of the plant are similar to the toxic white-flowered
meadow death-camas, a plant that is not in
Camassia, but part of the death-camas genus (
Toxicoscordion) and grows in the same areas. ==Taxonomy==