Coast Silk Tassel

Wavyleaf Silk Tassel
Garrya elliptica
NATIVE

Description (Jepson, PlantID.net)

• Eudicotyledon
  • Eudicots are a major lineage of flowering plants; see family for general characteristics
• Silk Tassel Family (Garryaceae)
• Evergreen shrub or small tree
• Leaves
  • Opposite (2 leaves at each junction with stem) and simple (not divided into leaflets)
  • Margin wavy and often rolled under
  • Leathery
  • Dark green upper surface; gray lower surface with soft, felt-like hairs
  • Up to 3 in. long
• Flowers
  • Dioecious (male and female flowers on separate plants)
    • Male flowers are gray-green catkins (long hanging clusters of small, petalless, unisexual  flowers), 3-8 in. long
    • Female flowers are stouter silver-gray catkins, 2-3.5 in. long
  • Ovary inferior (below the attachment of other flower parts)
• Fruit is a berry (a usually multi-seeded fruit with a fleshy ovary wall) in tight clusters
  • Initially hairy, green, and fleshy, becoming smooth, purplish, and brittle
• Height to 26 ft.

Distribution

• Native to California
  • Grows in coastal sage, chaparral, and mixed evergreen coastal forests
  • See Calflora for statewide observations of this plant
• Outside California, grows along the coast of southern Oregon
• Grows at elevations to 2,625 ft.

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

• Wildlife
  • Tough, bitter vegetation is not typically browsed by mammals
• Native people
  • Tea made from leaves was used to treat colds, stomachaches, and as a laxative
  • Wood was hardened with fire and used by Yuroks to pry mussels off rocks (San Jose State University)

Name Derivation

• Garrya (GARR-ee-a) – named for Nicholas Garry (c. 1782-1856), deputy governor of the Hudson Bay Company, in honor of the aid he provided to David Douglas in his 1826 exploration of the Pacific Northwest
• elliptica (el-IP-ti-ka) – elliptical, referring to the leaves
• Silk tassel – refers to the catkins

Notes

• Coast silk tassel, oaks, and grasses are examples of plants at Edgewood that are wind pollinated
  • About 12% of flowering plants and most conifers are wind pollinated (U.S. Forest Service)
  • These plants do not waste energy on flower features that attract animal pollinators; instead, their flowers generally have these characteristics
    • Small, petalless, and unscented, with muted colors
    • No nectar
    • Stamen (male flower part) and stigma (pollen-receiving part of the pistil/female structure) are exposed to air currents
    • Male flowers produce a great deal of pollen, which is very small, dry, and easily airborne, as all allergy sufferers know!
• Associated with the fungus-like microorganism Phytophthora ramorum, which causes Sudden Oak Death (SOD)
  • At Edgewood, the two species known to be highly susceptible to SOD are coast live oak (Quercus agrifolia var. agrifolia) and Pacific madrone saplings (Arbutus menziesii)
  • For a complete list of known hosts and host associates see USDA Risk Analysis for Phytophthora ramorum, pp. 6-9

ID Tips

• May be confused with several evergreen trees/shrubs at Edgewood
  • Coast live oak (Quercus agrifolia var. agrifolia)
  • Leather oak (Q. durata var. durata)
  • Holly-leaved cherry (Prunus ilicifolia ssp. ilicifolia)
• Check out this short video (Jepson 2020) for more ID tips

	Coast Live Oak	Leather Oak	Holly-leaved Cherry	Coast Silk Tassel
Leaves
Shape	ovate	oblong to elliptic	widely ovate to round	elliptic
Margin	often wavy and curled ⋯ some spines	wavy and curled ⋯ many spines	wavy, but not curled ⋯ many spines	often wavy and curled ⋯ no spines
Upper Surface	matte to shiny dark green ⋯ no hairs	matte to shiny dark green ⋯ hairs when new	very shiny bright green ⋯ no hairs	matte to shiny green ⋯ no hairs
Lower Surface	lighter green ⋯ possible hairy tufts at vein junctions	matte green ⋯ densely hairy	very shiny bright green ⋯ no hairs	gray-green ⋯ densely matted hairs
Flowers	male catkins and small, solitary females ⋯ on same plant	male catkins and small, solitary females ⋯ on same plant	bisexual flowers ⋯ in clusters	male and female catkins ⋯ on separate plants
Fruits	acorns	acorns	drupes	clustered berries

At Edgewood

• Found in chaparral and woodlands
  • Several silk tassels, including a large male, can be found trailside along the Franciscan trail, from posts 12-15
  • Look for a female plant on the uphill side of the upper Sylvan trail, near post 16
  • See iNaturalist for observations of this plant
• Catkins form in late summer; male catkins elongate and shed pollen December – April

See General References

Specific References

Friedman, J. and S. Barrett. 2009, Jun. Wind of change: new insights on the ecology and evolution of pollination and mating in wind-pollinated plants. Annals of Botany 103: 1515–1527. National Institutes of Health, United States National Library of Medicine, Center for Biotechnology Information.

Jepson Herbarium. 2020, Jan 15. Garrya elliptica (silk tassels) [Video]. The Jepson Videos: Visual Guide to the Plants of California. The Regents of the University of California. YouTube.

San Jose State University. Garrya elliptica. Botany Garden. Department of Biological Sciences.

U.S. Forest Service. Wind and water pollination. Forest Service. United States Department of Agriculture.