Scientific Name: Solanum rostratum
Synonyms: Androcera rostrata, Solanum cornutum
Common Names: Buffalobur Nightshade, Buffalobur, Buffalo Burr, Colorado Bur, Kansas Thistle, Mexican Thistle, Texas Thistle
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.
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.
Kingdom: Plantae – Plants
Subkingdom: Tracheobionta – Vascular plants
Superdivision: Spermatophyta – Seed plants
Division: Magnoliophyta – Flowering plants
Class: Magnoliopsida – Dicotyledons
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