The flowers and leaves of the oleander tree. The blossoms also come in red and white. The leaves of the oleander can be brewed into a toxic tea, featured as poisons in many literary works.

Recently, in California, an insect scourge of vineyards by the glassy winged sharpshooter (Homalodisca coagulata) has spread to oleander populations causing widespread deaths of the plants. The results have been dramatic, especially in areas where the oleander is used as a hedge between opposing lanes on freeways. You can see the sharpshooter by picking up the object below.

For Didion's reference, see page 169.