Blue Witch

Blue Witch Nightshade
Solanum umbelliferum var. umbelliferum
NATIVE

Description (Jepson, PlantID.net)

• Eudicotyledon
  • Eudicots are a major lineage of flowering plants; see family for general characteristics
• Nightshade Family (Solanaceae)
• Evergreen to deciduous shrub
• Stems green and densely hairy
• Leaves oval and hairy
• Flowers
  • Inflorescence (flower arrangement) is a loose cluster of blue-purple flowers at the top of stems
  • Each flower has 5 fused petals and sepals (usually green, outer flower parts)
    • Prominent, thick, yellow anthers (pollen-producing part of the stamen/male structure) surround the protruding pistil (female flower part)
    • Base of each petal has 2 green spots
  • Ovary superior (above the attachment of other flower parts)
• Fruit is a berry (a usually multi-seeded fruit with a fleshy ovary wall), initially green, becoming purple when mature
• Height to 2-3 ft.; may grow wider than its height

Distribution

• Native to California
  • Grows in chaparral and low-elevation oak woodlands
  • See Calflora for statewide observations of this plant
• Outside California, grows in Arizona and south into Baja California, Mexico
• Grows at elevations to 5,200 ft.

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

• Wildlife
  • Fruit eaten by birds
  • Frequented by bumblebees and other native bees capable of “buzz pollinating”
• Native people
  • Ate the fruit (preparation is undocumented)
• CAUTION – The glycoalkaloid solanine, which is toxic to people and some animals, is in all plant parts, including leaves, fruit, and tubers, of many Solanum species

Name Derivation

• Solanum (so- LAY-num) – from the Latin solari, “to soothe” or “to quiet,” referring to the narcotic properties of some species (e.g. Datura species)
• umbelliferum (um-bel-IF-er-um) – from the Latin for “bearing an umbel” (a spoke-like flower cluster with stalks radiating from a single point), referring to the umbel-like flower clusters
• Blue witch – “witches’ weeds” is a name used for some Nightshade species, as their poisonous properties made them common ingredients of potions and imagined witches’ brews

Notes

• Nightshades (Solanum species), California poppies (Eschscholzia species), and wild roses (Rosa species) are examples of plants with nectarless flowers that offer only pollen
  • Pollen provides no immediate energy, so bees foraging on these flowers must intermittently visit nectar-bearing plants to keep their sugar buzz! (Thorp 2002)
• Pollinated most effectively by sonication or “buzz pollination”; see Nightshade family for details
• Flowers close at night to protect pollen
  • This process is an example of photonasty, a nastic response to light 
  • Nastic responses occur when a plant part, such as a flower or leaf, moves in response to a stimulus (Mauseth 2012), e.g., humidity (hydronasty), light (photonasty), temperature (thermonasty), or touch (thigmonasty)
    • Nastic responses are caused by changes in turgor pressure 
    • They are independent of the direction of the stimulus and usually are reversible and repeatable
  • Nastic responses differ from tropic responses
    • Tropic responses are directional growth movements—a plant grows toward or away from a stimulus, e.g., light (phototropism), gravity (gravitropism) or touch (thigmotropism)
    • All plants have tropic responses, but only some plants have nastic responses
• Drought-deciduous as well as winter-deciduous
  • Sheds leaves during the summer to conserve water
  • Stems are green, so plant can continue photosynthesis when leafless

At Edgewood

• Found in chaparral and woodlands
  • See iNaturalist for observations of this plant
• Flowers January – September

Specific References 

Breckling, B. 2008. Spring Wildflowers of Henry W. Coe State Park and the Inland San Francisco Bay Area. Pine Ridge Association.

Mauseth, J. 2012. Botany: An Introduction to Plant Biology (5th ed.). Jones & Bartlett Learning. Burlington, Massachusetts.

Solanaceae Source. Morphology.

Thorp. R., P. Schroeder, and C. Ferguson. 2002. Bumble bees: Boisterous pollinators of native California flowers. Fremontia 30(3-4): 26-31.

General References

Calflora Database. 2014. Berkeley, California.

Calscape. 2018. California Native Plant Society.

Charters, M.L. 2015. California Plant Names: Latin and Greek Meanings and Derivations.

Charters, M.L. 2017. Southern California Wildflowers: Guide to the Pronunciation of Specific, Generic and Family Names.

Corelli, T. 2004. Flowering Plants of Edgewood Natural Preserve (2nd. ed.). Monocot Press, Half Moon Bay, California.

Dave’s Garden.

Elpel, T.J. 2013. Botany in a Day: The Patterns Method of Plant Identification. HOPS Press, Pony, Montana.

Flora of North America. efloras.org.

Harris, J.G., and M.W. Harris. 2013. Plant Identification Terminology: An Illustrated Glossary. Spring Lake Publishing, Spring Lake, Utah.

Keator, G. 2009. California Plant Families. University of California Press, Berkeley and Los Angeles, California.

Native American Ethnobotany DB.

Regents of the University of California. Jepson eFlora. Jepson Herbarium. University of California, Berkeley.