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- Nightshade Family: Solanaceae
Hairy nightshade (Solanum physalifolium)
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Hairy nightshade is a summer annual broadleaf. In California it is found in the North Coast, Central Coast, western San Francisco Bay region, western South Coast Ranges, Klamath Ranges, Cascade Range foothills, Central Valley, and Santa Cruz Island up to 3300 feet (1000 m). It inhabits agricultural land and other disturbed areas. It is one of the most problematic of the nightshades.
Nightshades are considered weeds because they can harbor diseases and pests that affect closely related crops such as tomatoes, potatoes, and peppers. Some nightshade biotypes are resistant to certain herbicides. Another issue with hairy nightshade is that mature plants can form a sticky mass that clogs harvesting machinery. Nightshades contain several glycoalkaloid compounds that can be toxic to humans and livestock when consumed. The level of toxicity depends on factors such as plant maturity and environmental conditions.
Habitat
Orchards, vineyards, crop fields, pastures, gardens, yards, fields, roadsides and other disturbed, unmanaged sites.
Seedling
Cotyledons (seed leaves) are narrowly egg shaped to lance shaped and about 1/6 to 2/5 of an inch (4–10 mm) long. The stalk below the cotyledons is usually covered with glandular hairs. First true leaves of hairy nightshade have wavy edges and prominent veins. Later leaves are increasingly larger, egg shaped, dark green and often purple tinged, with a smooth to slighly wavy edge, and covered with glandular hairs. Black nightshade seedlings are similar but have nonglandular and some glandular hairs.
Mature plant
Hairy nightshade is a bushy plant that reaches 3-1/3 feet (0.9 m) tall. Perennial forms of the plant sometimes are slightly woody at the base. Althoughs leaves vary they are overall egg shaped with a smooth to wavy edge or an irregular, shallow-toothed edge. Leaves are alternate to one another along the stem. Leaves have numerous conspicuous, fine, short hairs, especially along the underside of the main vein, distinguishing it from black nightshade, which is inconspicuously covered with minute hairs.
Flowers
Flowers bloom from May through October. Two to eight star-shaped, usually white flowers grow in a cluster. The inside of the petals sometimes are flecked with purple. Another species, silverleaf nightshade, S. elaeagnifolium, has colorful showy flowers.
Fruits
Mature berries are glossy, yellowish green to purplish green or light brown, never black. Green lobes cover more or less half of the berry. Another species, silverleaf nightshade has yellow to orange berries. Black nightshade berries are black or purplish black.
Reproduction
Reproduces by seed.
Related or similar plants
- Black Nightshade, Solanum nigrum
- Silverleaf Nightshade, Solanum elaeagnifolium
More information
- Broadleaf ID illustration
- Calflora's distribution map
- For agriculture: UC IPM Pest Management Guidelines