Holly-leafed Cherry, Islay
Prunus ilicifolia ssp. ilicifolia
NATIVE
Description (Jepson, PlantID.net)
- Eudicotyledon
- Eudicots are a major lineage of flowering plants; see family for general characteristics
- Rose Family (Rosaceae)
- Evergreen tree or shrub, usually compact and densely leaved
- All other native California Prunus species are deciduous
- Leaves
- Simple (not divided into leaflets) and alternate (1 leaf at each junction with stem)
- Ovate to round, thick and wavy, with spiny-serrate margins
- Shiny dark-green upper surface; light-green underside
- Up to 2 in. long
- Flowers
- Inflorescence (flower arrangement) is a many-flowered raceme (unbranched stem with stalked flowers opening from the bottom up)
- Small, white, 5-petaled flowers
- Hypanthium (floral cup formed from the fusion of petals, sepals, and stamens) is deciduous in fruit
- Ovary superior (above the attachment of other flower parts)
- Fruit a small red or dark-purple drupe (a fleshy fruit with usually 1 seed in a hard inner shell–a stone fruit)
- Height to 30 ft.
- Life span may exceed 100 years
Distribution
- Native to California
- Common shrub component in foothill woodlands, chaparral, and coastal scrub
- See Calflora for statewide observations of this plant
- Outside California, grows into Baja California, Mexico
- Grows at elevations to 5,250 ft.
Uses (San Mateo County Parks prohibits removal of any natural material)
- Wildlife
- Pollen and nectar source for bees
- Larval food source (host) for many butterflies, e.g. California hairstreak (Satyrium californica), Lorquin’s admiral (Limenitis lorquini), western swallowtail (Papilio rutulus), and pale swallowtail (P. eurymedon)
- Berries eaten by birds, small mammals, and deer
- Leaves browsed by deer
- Native people
- Fruit eaten fresh or fermented to make an alcoholic drink
- Fruit kernel (pit) ground and carefully leached to remove cyanide-producing chemicals before roasting and grinding into flour (Anderson 2005)
- Infusion of leaves and bark taken as a cough medicine
- Wood used for bows
- Trees were actively managed by pruning and burning, stimulating many positive effects (Anderson 2005)
- Vigorous and straighter shoots
- Larger and more numerous fruits
- Less congested canopies
- Reduced insect infestations
- Recycled nutrients
- CAUTION – Fleshy part of the fruit is sweet and edible, but other plant parts, including the seeds, are poisonous
- In the Prunus genus, all plant parts (i.e. leaves, shoots, bark, and pits), except for the mature, outer fleshy fruits contain cyanide-producing chemicals (Wright 2008)
- Crushed leaves smell like almond, an indication of cyanide!
Name Derivation
- Prunus (PROO-nus) – Latin for “plum”
- ilicifolia (il-is-i-FO-lee-a) – from the Linnaean classification of Ilex for holly (ilex was originally the classical Latin name for the Mediterranean holm oak, which has holly-like leaves) and the Latin folia, “leaf”; thus, “having leaves like holly” (Shorter Oxford 2007)
Notes
- Leaves have several defenses against herbivory
- Contain cyanide-producing chemicals
- Spines also deter animals from eating the leaves
- Component 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 holly-leaved cherry, 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
- Although holly-leaved cherry is common in fire-prone environments, the seeds do not survive fire; instead, the plant resprouts from the root crown
- Only evergreen member of the Prunus genus native to California
- Edgewood’s holly-leaved cherry is classified as a subspecies
- Subspecies indicates a geographically-separated population with distinct morphological characteristics; when not isolated, interbreeding is possible
- Variety indicates a population with small morphological variations, e.g. color, seen throughout the geographic range of the species; interbreeding is possible
- In practice, botanists have not consistently applied these ranks
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)
- Coast silk tassel (Garrya elliptica)
| 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 open woodlands
- Found trailside along lower Sylvan trail between Baywood Glen trail (post 7) and Serpentine trail (post 16)
- Look for the lone, tree-sized holly-leaved cherry at the sharp Sylvan trail switchback; nearby for comparison is a leather oak and coast live oak
- See iNaturalist for observations of Prunus ilicifolia
- Found trailside along lower Sylvan trail between Baywood Glen trail (post 7) and Serpentine trail (post 16)
- Flowers March – June
- Fruit ripens in fall
Specific References
Anderson, M.K. 2005. Tending the Wild. University of California, Berkeley. Pp. 274-280.
Baumann, L. 2017, Oct. 14. Holly-leaved cherry. Santa Monica Trails Council, Agoura Hills, California.
McMurray, N.E. 1990. Prunus ilicifolia. Fire Effects Information System. United States Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory.
Ritter, M. 2018. California Plants: A Guide to Our Iconic Flora. Pacific Street Publishing, San Luis Obispo, California.
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.
Shorter Oxford English Dictionary (6th ed.). 2007. Holly. United Kingdom: Oxford University Press.
Wright, B., A. Bebbington, and T. Leuty. 2008, July. Prunus poisoning in horses and other livestock. Infosheet. Ontario Ministry of Agriculture, Food and Rural Affairs, Ontario, Canada.