As a habitat type, the vernal pool is something particularly special. A vernal pool is formed when a low area develops a hard, impermeable sub-surface layer that allows water to accumulate during the wet season, which in most of California is the winter. What makes vernal pools so special is that they are transient communities, bursting into life during the brief period of water availability, before dying back when the water dries up. This boom and bust cycle leads to short but spectacular displays of flowers when the pools are filled.
Many of the plants found in vernal pools are found nowhere else, making them exceptionally valuable as havens of biodiversity. However, many of the vernal pools are imperiled, due to human activity. Grazing in vernal pool habitat and development both have a serious, negative effect on the pools, from disruption to outright destruction. As such, it is of the utmost importance that the remaining pools are protected as well as studied to ensure that what is left doesn't vanish without a trace.
Found in vernal pools, Isoëtes howellii is a member of the larger of two clades of Isoëtes found in North America. Larger than any of the other diploid species of found in California, this species is subjected to annual dedication when the pools they grow in dry up. 
A class 1B.2 species, Arctostaphylos hookeri var. hookeri is found along the coast of California in Monterrey County growing in chaparral type habitats. Like most Arctostaphylos, this species can be hard to identify without a significant amount of experience in keying the group.
A perennial, woody member of the Phlox family, Linanthus californicus is found predominantly along the south-western edge of California. These plants are found growing mostly in scrub and forest habitats, but can also occur in chaparral. They are most obvious when in flower, which are open during the day, and are rosy pink to magenta.
