Torreya californica is a species of conifer endemic to California, occurring in the Pacific Coast Ranges and the foothills of the Sierra Nevada.

[4] As with all species of Torreya, the male (pollen) cones are 5–7 mm long, grouped in lines along the underside of a shoot.

[4] On serpentine rock, California torreya becomes a stunted tree or shrub and occurs only on north-facing slopes in coastal chaparral.

[4] Mountainous terrain affords this narrowly dispersed ancient conifer opportunities to track suitable microclimates by shifting altitude and local topography, along with shifts between northerly (cool) and southerly (warm) slope aspects or deep ravines and canyons, while remaining on the same mountain.

This pattern of distribution is suggestive of a relict taxon that has had difficulties navigating episodes of climate change in which range shifts had to occur in topographically complex landscapes.

A sister species in eastern North America, Florida torreya, was reduced to only a single population owing to episodes of climate change during the Quaternary glaciation.

[6] Torreya species are all adapted to establish and grow slowly as subcanopy woody plants in forest habitats of moderate to dense shade.

In this way, their leaf structure and growth habit resemble species of yew, genus Taxus, which is a close relative.

Owing to their ability to resprout from the root crown after logging or mild fire, the species will experience growth opportunities in the early stages of regrowth forest habitats.

Because the Torreya genus has very long-lived roots, it can continue slow growth, while replenishing basal stems, for many decades without seed production becoming crucial for the persistence of a local population.

On this basis a past decline of more than 50% of mature trees in the population has been inferred over the past 150 years (three generations), leading to an assessment of Vulnerable under the A1 criterion.... Logging in the late 19th and up to the mid 20th centuries virtually eliminated California Nutmeg from the Vaca Mountains of Napa and Solano counties, and considerably reduced populations in the Santa Cruz Mountains and lower Russian River area of Sonoma County (Howard 1992).

Perhaps this is because the most recent IUCN assessment is listed as April 2011 — just before the extraordinary increase in the scale and intensity of California wildfires.

It was already showing signs of decline, including moss indicative of very slow growth on the multiple stems of its crown and on its trunk.

[4] The wood is sometimes used in making Go game boards, as a cheaper substitute for the prized kaya (Torreya nucifera) of Japan and Southeast Asia.