California Department of Fish and Wildlife
Atlas of the Biodiversity of California


Why did we choose the illustrations in the Atlas?

Solano grass (Tuctoria mucronata)

By Diana Hickson

Solano grass (Tuctoria mucronata), also called Crampton's Orcutt grass, was chosen to represent biodiversity in California in general (see Atlas page v). It is one of a group of closely-related grasses, all of which are endangered. The group also includes Colusa grass (Neostapfia colusana) and the five species in the genus Orcuttia, all known as Orcutt grasses: California (O. californica), San Joaquin Valley (O. inaequalis), hairy (O. pilosa), slender (O. tenuis), and Sacramento Orcutt grass (O. viscida). The seven grasses in this group evolved to exist in specific types of vernal pools and all but one are found only in California .

Solano grass is a sticky, aromatic annual grass from vernal pools that is hovering on the edge of extinction. Solano grass has only been found in three places in the Central Valley . It has not been seen at the Solano County location from which it was originally described (called the "type locality") in over 10 years. The second site is on private land in Solano County and has experienced steady declines over the past few decades, with only 38 plants seen in 2000 (the last year it was surveyed). The third site has also declined from over 10,000 plants in 1993 to a little under 2,000 plants in 2001. Competition from non-native weeds is thought to be affecting at least this last location.