Chamise

Greasewood
Adenostoma fasciculatum var. fasciculatum
NATIVE

Description (Jepson, PlantID.net)

• Eudicotyledon
  • Eudicots are a major lineage of flowering plants; see family for general characteristics
• Rose Family (Rosaceae)
• Evergreen shrub that is diffusely branched and resinous
• Bark becomes gray and shreds with age
• Leaves
  • Small, hard, and needle-like
  • Bright green and shiny with pungent volatile oils
  • Clustered along the stems
• Flowers
  • Inflorescence (flower arrangement) is a panicle (branching stem with flowers opening from the bottom up) at the branch tips
  • Many tiny, white, 5-petaled, tubular flowers
  • Ovary inferior (below the attachment of other flower parts)
• Fruit is an achene (a single-seeded, dry fruit that does not split open)
• Height to 13 ft.
• Lifespan may reach 100-200 years

Distribution

• Native to California
  • Grows in chaparral, and as an understory shrub in woodlands
  • 50-54% of plants occur on ultramafic soils, e.g. serpentine; see ultramafic affinity rankings (Calflora per Safford and Miller 2020)
  • See Calflora for statewide observations of this plant
• Outside California, grows in Oregon, Nevada, and northern Baja California, Mexico
• Grows at elevations to 5,000 ft.

Uses (San Mateo County Parks prohibits removal of any natural material)

• Wildlife
  • Provides cover and nesting sites for many smaller birds and mammals
  • Tender plant sprouts browsed by deer
  • Larval food source (host) for the echo blue butterfly (Celastrina ladon echo)
• Native people and Spanish-Mexicans
  • Decoction of leaves and branches to treat infections and inflammation
  • Traditional remedy for colds, convulsions, snake bites, cramps, and lockjaw
  • Branches used to build ramadas and fences, for basketry and firewood, and bound together for torches
  • Scale insects found on plants used to make a binding agent for arrows and baskets

Name Derivation

• Adenostoma (ad-en-OS-to-ma) – from the Greek adena, “gland,” and stoma, “mouth,” referring to glands at the mouth of the sepals (usually green, outer flower parts)
• fasciculatum (fa-sik-yoo-LAY-tum) – from the Latin fascis, “a bundle,” referring to the fascicled (tightly clustered) leaf arrangement
• Chamise – from the Spanish chamisa, “dry brush” or “firewood”

Notes

• Chamise is the predominant shrub of California chaparral
  • Chaparral refers to evergreen shrub and small tree communities that grow on shallow, rocky, nutrient-poor soils in Mediterranean climates, with mild, wet winters and hot, dry summers
  • Chaparral shrubs, like chamise, are examples of sclerophyllous (“hard-leaf”) vegetation, with leaves that conserve water by being
    • Thick and leathery, with extra lignin (structural component that stiffens plant tissue) to prevent wilting
    • Waxy, with a thick cuticle that reduces transpiration
    • Densely organized, occurring at short distance along the stem, thus increasing local humidity
    • Usually small and oriented parallel or oblique to direct sunlight, reducing surface exposure
  • Volatile oils of chamise leaves also help preserve moisture, as well as deter herbivory
    • These oils, also present in the branches and trunks of chamise, increase the intensity of chaparral fires
• Can form dense monotypic stands and be dominant on the hottest, driest locations
• Dense nature of growth and accumulation of water-soluble phenolics (allelopathic toxins) from the leaves inhibit germination and understory growth of other species
• Develops an extensive root system
  • Multiple taproots can penetrate fractured rock to depths of 10-12 ft.
• Chamise is well adapted to fire and regenerates quickly from the root crown and dormant seeds
  • Fire stimulates growth from the lignotuber, a woody swelling at the base of the shrub that provides fire-resistant storage of energy and sprouting buds
  • Fire also stimulates the germination of dormant seeds that have built up in the soil
    • Over 90% of dormant seeds will germinate in the first year after a fire
    • Seeds are fire facultative, not fire obligate, meaning that fire can stimulate, but is not necessary, for germination
    • Some seeds will germinate without fire, but the one-year survival rate for seedlings is extremely low without a gap in the canopy
• Edgewood’s chamise is classified as a variety
  • Subspecies rank is used to recognize geographic distinctiveness, whereas variety rank is appropriate for variants seen throughout the geographic range of the species; in practice, these two ranks are not distinct

ID Tips

• Check out this short Jepson video

At Edgewood

• Found in chaparral
  • See iNaturalist for observations of Adenostoma fasciculatum
• Flowers May – July

See General References

Specific References

CAB International. Data Sheet: Adenostoma fasciculatum (chamise). Invasive Species Compendium.

McMurray, N.E. 1990. Adenostoma fasciculatum. Fire Effects Information System. United States Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory.

Montalvo, A.M., E.C. Riordan, and J.L. Beyers. 2017. Plant profile for Adenostoma fasciculatum. Native Plant Recommendations for Southern California Ecoregions. Riverside-Corona Resource Conservation District and United States Department of Agriculture, Forest Service, Pacific Southwest Research Station, Riverside, California.

Safford, H.D. and J.E.D. Miller. 2020. An updated database of serpentine endemism in the California flora. Madroño 67: 85-104. BioOne Complete.

Shapiro, A.M. and T.D. Manolis. 2007. Field Guide to Butterflies of the San Francisco Bay and Sacramento Valley Regions. University of California Press, Berkeley and Los Angeles, California.