Plant Name

Scientific Name: Solanum rostratum

Synonyms: Androcera rostrata, Solanum cornutum

Common Names: Buffalobur Nightshade, Buffalobur, Buffalo Burr, Colorado Bur, Kansas Thistle, Mexican Thistle, Texas Thistle

Plant Characteristics

Duration: Annual

Growth Habit: Herb/Forb

Arizona Native Status: Native

Habitat: Desert, Upland, Mountain. This weed grows in waste areas and disturbed areas and is especially common in overgrazed pastures.

Flower Color: Yellow

Flowering Season: Spring, Summer

Height: To 30 inches (76 cm) tall

Description: The flowers are 1 inch (2.5 cm) across and have 5 broad lobes and 5 projecting, beak-like anthers. Four of the anthers are straight and one is larger and curved. The flowers are followed by round, spiny, green fruits (burs). The leaves are dark green and deeply pinnately lobed like those of a watermelon plant. The entire plant is covered in numerous, wickedly sharp, stinging spines.

Special Characteristics

Poisonous – The plants, especially the leaves and green fruit, are poisonous and contain the glycoalkaloid solanine as well as other tropane alkaloids. The plants can also accumulate toxic levels of nitrates from the soil.

Stinging or Itching – The numerous sharp spines on the plants and burs can cause intense, lingering pain if touched. Animals are also affected, and even after the burs are removed, dogs will continue to lick and chew on their feet because of the pain.

Classification

Kingdom: Plantae – Plants
Subkingdom: Tracheobionta – Vascular plants
Superdivision: Spermatophyta – Seed plants
Division: Magnoliophyta – Flowering plants
Class: Magnoliopsida – Dicotyledons
Subclass: Asteridae
Order: Solanales
Family: Solanaceae – Potato family
Genus: Solanum L. – nightshade
Species: Solanum rostratum Dunal – buffalobur nightshade

More About This Plant

Arizona County Distribution Map
Buffalobur Nightshade (Solanum rostratum), A Very Evil Plant – The Firefly Forest