Stats

Lifespan: Annual
Size: Medium
Diet: Photosynthetic
Biome: Temperate grassland
Range: Mediterranean
Movement: Sessile
Breeding: Seeds
Defense: Spines
Status: Common

About

Italian thistle is a slender annual or biennial weed introduced from the Mediterranean that now invades disturbed roadsides and grasslands across western North America. Each plant can produce over 4,000 wind-dispersed seeds, making it one of the most prolific invasive thistles in California.

Life cycle

1.
seed
A dormant seed waits for water and warmth before germinating.
2.
sprout
A first shoot emerges with cotyledon leaves and a tap root reaching down.
3.
sapling
A young plant grows true leaves and a stem or trunk, putting on height each season.
4.
mature
Fully grown, flowering or fruiting at adult size.

Learn more

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Taxonomy

Kingdom: Plantae
Phylum: Tracheophyta
Class: Magnoliopsida
Order: Asterales
Family: Asteraceae
Genus: Carduus
Species: Carduus pycnocephalus