Because of the showy blossoms characteristic of the family, many species are cultivated as ornamentals. This is the chief economic value of the Liliaceae; over 160 genera are represented in American trade. Types of hyacinth, lily, meadow saffron, squill, and tulip constitute the bulk of the "Dutch bulb" trade. Yucca and aloe species are popular succulents; the latter is also a drug source. Asparagus and plants of the onion genus are the only liliaceous food plants of commercial importance. A small tropical tree was the original source of dragon's blood.