Quercus Kelloggii - Ecology

Ecology

The California black oak, Quercus kelloggii, is a critical species for wildlife. Oaks (Quercus spp.) may be the single most important genus used by wildlife for food and cover in California forests and rangelands, and California black oak occupies more total area in California than any other hardwood species. Livestock also make heavy use of this species for food and cover.

Cavities in the trees provide den or nest sites for owls, various woodpeckers, tree squirrels, and American black bears. Trees provide valuable shade for livestock and wildlife during the hot summer months. California black oak forest types are heavily used for spring, summer, and fall cover by black bear.

It is browsed by mule deer and livestock. Acorns are heavily utilized by livestock, mule deer, feral pigs, rodents, mountain quail, Steller's jay, and woodpeckers. Acorns constitute an average of 50% of the fall and winter diets of western gray squirrel and black-tailed deer during good mast years. Fawn survival rates increase or decrease with the size of the acorn crop.

It is a preferred foraging substrate for many birds. All of 68 bird species observed in oak woodlands of the Tehachapi Mountains of California used California black oak for part of their foraging activities. Acorn woodpecker, Bullock's oriole, and Nashville warbler show strong preference for California black oak. The parasitic plant Pacific mistletoe (Phoradendron villosum), which commonly grows on this oak, produces berries which attract birds as well.

Many animals cache the acorns, and acorns that have been stored in the ground or otherwise buried are more likely to sprout than those that remain on the surface.

The tree is adapted to wildfire. It is protected from smaller fires by its thick bark. If it is top-killed and burned away in a larger fire, it easily resprouts and has a good supply of nutrients and water stored in its root system. Acorns sprout into seedlings after fire and sites that have been cleared of canopy and leaf litter in fires are ideal for seedling success.

This oak is vulnerable to sudden oak death.