The fibers surrounding the bulb were widely used, bound together, to make small brushes.
Extracts of the bulbs could also be used as a sealant or glue.

Cleansing
The juices of the bulb contain saponins that form a lather when mixed with water, and both Native American people (e.g. Miwok tribe) and early European settlers used the bulbs as a kind of soap; this is the origin of the plant's name.
 It was particularly used for washing hair, since it was held to be effective against dandruff.

Cuisine
The young leaves can be used as food, but the saponins in the bulbs make these poisonous.
However saponins are very poorly absorbed by the body and usually pass straight through, and in any case they can be destroyed by thorough cooking.
 The Miwok people roasted and ate the bulbs as a winter food.
In February 1847 Patrick Breen of the ill-fated Donner Party recorded that a Native American gave the starving settler some "roots resembling Onions in shape [that] taste some like a sweet potatoe [sic], all full of little tough fibres."
Breen's son later called the roots "California soap-root"—almost certainly C. pomeridianum.

Saponins are much more toxic to some other animals than they are to humans.
 Fish are particularly susceptible, and the bulb juices were used to kill or stun them so they could be caught easily.

Medicinal
The bulbs also had various medicinal uses, both external (e.g., for making a poultice to be used as an antiseptic, or as a rub in cases of rheumatism) and internal (decoctions were used for a range of purposes, including as a diuretic, as a laxative and against stomachache).
The fibers surrounding the bulb were widely used, bound together, to make small brushes. Extracts of the bulbs could also be used as a sealant or glue.
Cleansing
The juices of the bulb contain saponins that form a lather when mixed with water, and both Native American people (e.g. Miwok tribe) and early European settlers used the bulbs as a kind of soap; this is the origin of the plant's name.  It was particularly used for washing hair, since it was held to be effective against dandruff.
Cuisine
The young leaves can be used as food, but the saponins in the bulbs make these poisonous. However saponins are very poorly absorbed by the body and usually pass straight through, and in any case they can be destroyed by thorough cooking.  The Miwok people roasted and ate the bulbs as a winter food. In February 1847 Patrick Breen of the ill-fated Donner Party recorded that a Native American gave the starving settler some "roots resembling Onions in shape [that] taste some like a sweet potatoe [sic], all full of little tough fibres." Breen's son later called the roots "California soap-root"—almost certainly C. pomeridianum.
Saponins are much more toxic to some other animals than they are to humans.  Fish are particularly susceptible, and the bulb juices were used to kill or stun them so they could be caught easily.
Medicinal
The bulbs also had various medicinal uses, both external (e.g., for making a poultice to be used as an antiseptic, or as a rub in cases of rheumatism) and internal (decoctions were used for a range of purposes, including as a diuretic, as a laxative and against stomachache).
Chlorogalum pomeridianum