Solanum rostratum Dunal


Solanum rostratum is an annual herbaceous plant that can grow up to 2 ft. (0.6 m) tall.
Stems and leaves have extremely sharp spines, so take care when handling. Leaves are alternate, bright green, petiolate, 4-5 in. (10.2-12.7 cm) long, and pinnately lobed.
Flowers have five petals and are yellow, and 1 in. (2.5 cm) across. Calyx tube is 1 in. (2.5 cm) long, and spiny. Flowering occurs from May to October.
Fruits are dry berries up to 0.4 in. (1 cm) in diameter covered in sharp spines and contain several wrinkled, flat, black seeds.
Ecological Threat
S. rostratum prefers moist soils and areas like pastures, waste ground, and roadsides. Although it is native to most of North America, it is considered a noxious weed in some states.

Selected Images


EDDMapS Distribution

EDDMapS Distribution - This map is incomplete and is based only on current site and county level reports made by experts, herbaria, and literature. For more information, visit www.eddmaps.org

State Regulated List

State Regulated List - This map identifies those states that list this species on their regulated list. For more information, visit Invasive.org

State Regulated List
   No Data for this state
   Troublesome or Common weed in one or more crops

Most Troublesome / Most Common Agricultural Weed List
This map identifies those states that consider this species either most troublesome or most common in at least one commodity. For more information, visit the MTMC project page.

Taxonomic Rank

Kingdom: Plantae
Phylum: Magnoliophyta
Class: Magnoliopsida
Subclass: Asteridae
Order: Solanales
Family: Solanaceae
Genus: Solanum
Subject: Solanum rostratum Dunal

Synonyms and Other Names

Other Common Names:
buffalobur nightshade, buffalobur, Colorado bur, horned nightshade, Kansas thistle, Mexican thistle, Texas thistle


Plants - Forbs/Herbs