C. Michael Hogan PhD
September 16, 2008
Toyon is a common shrub in far western USA; the species is a common member of plant associations which include oak woodland, evergreen forest, chaparral and transitional coastal scrub/chaparral. The species can attain a height of six meters and produces plentiful red berries that are consumed by wildlife; moreover, this taxa was a key part of the Native American diet within the species distribution pattern. Lifespan of this plant is unusually long for a chaparral plant, and can exceed 100 years.
H. arbutifolia occurs commonly in mixed oak woodland, mixed evergreen forest and chaparral from California's Humboldt County south to Baja California. This occurrence generally does not exceed an elevation of 1300 meters and coincides with much of the extent of the California Floristic Province. Toyon occurs in the California North and South Coast Ranges as well as foothills of the Sierra Nevada from central California southward into the Transverse Ranges. Disjunctive populations of var. macrocarpa are restricted to the Santa Catalina and San Clemente islands off the coast of Southern California
In the North Coast Range and foothills of the northern Sierra Nevada, toyon and chamise may co-dominate open serpentine chaparral communities. (Hanes) It is one of several woody dominants in Adenostoma fasciculatum chaparral, Quercus dumosa chaparral, and mixed chaparral communities. In the southern portion of the Coast Ranges and in Southern California chaparral, toyon can be locally dominant in seral communities transitional between coastal sage scrub. (Bolsinger) In the Coast Ranges toyon is frequently a conspicuous subdominant in Q. agrifolia north slope woodlands, and may become dominant within these communities in the central part of the California Coast Range.
Toyon manifests as either a shrub or small tree, typically from two to six meters in height. Bark and stems are grayish and twigs are puberulent. The simple, elliptic to oblong leaves have a short petiole, and these leathery, sharply toothed leaves display a shiny dark green above and duller green underneath. The leaves are arranged alternately and are four to 12 cm long.
The terminal inflorescence is in the form of a panicle, with many flowers. The more or less obconic hypanthium measures two to three mm; sepals are one to two mm in size, with white petals two to four mm .(Jepson) There are ten stamens occurring in pairs opposite sepals; one pistil is presented, and the ovary is two to three chambered. There are two or three styles. Bright red round fruits are in the form of mealy pulped pomes, four to nine mm across. The compressed brown seeds number three to six.
ECOLOGY AND REPRODUCTION
Common flora shrub associates within scrub oak chaparral include Prunus ilicifolia, Cercocarpus betuloides, Rhamnus crocea, Rhamnus california, Ceanothus crassifolius, C. leucodermis, chamise, Toxicodendron diversilobum,(Patric) and a wide variety of Arctostaphylos species. Toyon is also a key component of communities which are transitional between chaparral and coastal sage scrub types. Artemisia californica, Eriogonum fasciculatum, Lotus scoparius, sage and Arctostaphylos taxa are understory associates within transitional communties
Architecturally, Toyon is a useful species in scrub oak and chaparral communities, since it provides a differing level of cover and nesting opportunity from other flora in those palettes. H.arbutifolia plays an important role in erosion control and forest regeneration after fire, because of the robust and extensive root system that regenerates relatively rapidly following disturbance. Fruits are extensively browsed by an assortment of wildlife, notably birds such as California quail and band-tailed pigeon. Toyon is of importance as for raccoon, deer and many other mammals.
Seed dispersal is conducted chiefly by birds and other animals, with germination being favored by unusually wet years, a circumstance causing high seed yields and also producing moist soils hospitable for seedling production. Germination is episodic within these events of greater rainfall years, especially in forest openings which deliver sunlight and growing space to the forest (or chaparral) floor.
* Jepson Manual (1993) Regents of the University of California
* Ted L.Hanes (1974) Vegetation types of the San Gabriel Mountians. In: June Latting ed. Symposium proceedings: plant communities of Southern California; Fullerton, Ca. Special Publication No. 2., Berkeley, CA: California Native Plant Society: 65-76
* Charles L. Bolsinger (1989) Shrubs of Californias chaparral, timberland, and woodland: area, ownership, and stand characteristics'', Res. Bull. PNW-RB-160. Portland, Oregon: U.S. Department of Agriculture, U.S. Forest Service, Pacific Northwest Experiment Station. 50 p
* James H. Patric and Ted L.Hanes (1964) Chaparral succession in a San Gabriel Mountain area of California, Ecology. 45(2): 353-360