# spotted knapweed (*Centaurea stoebe*) Spotted knapweed is a pretty flower with purple petals and dark spots. It grows in fields and can be found in many places, making the world a little brighter! - **Category:** [Plants](https://www.snappit.app/explore/categories/plant) - **Rarity:** Common - **Danger:** 1/5 · Very low - **Snaps:** 8 - **Habitat:** Grasslands - **Also known as:** Centaurea, Knapweed ![spotted knapweed](https://commons.wikimedia.org/w/index.php?title=Special:Redirect/file/Centaurea_stoebe_281007b.jpg&width=800) Photo: Bernd Haynold, CC BY-SA 3.0 · [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Centaurea_stoebe_281007b.jpg) ## Appearance The spotted knapweed has thistle-like purple-pink flowers that bloom atop stiff, branched stems. Look for the distinctive black-tipped bracts (leaf-like structures) beneath its flower heads, giving it a 'spotted' look and making it visually different from similar wildflowers. ## Taxonomy - **Kingdom:** Plantae - **Phylum:** Tracheophyta - **Class:** Magnoliopsida - **Order:** Asterales - **Family:** Asteraceae - **Genus:** Centaurea ## Interesting facts - It's sometimes called 'star thistle' because of its bracts! - Its taproots can dive over 6 feet deep underground! - One plant can produce over 1,000 seeds in a single year! - This plant is a 'super spreader' in many new habitats. ## Special abilities - **Chemical Power:** Spotted knapweed releases root chemicals that stop other plants from growing, helping it claim more space and nutrients. - **Deep Drinker:** Its long taproot, which can reach 6 feet deep, helps it find water and nutrients others can't. - **Seed Hoarder:** It produces thousands of seeds that can stay viable in the soil for many years, waiting to sprout. ## Measurements & details - **Height:** 30-150 cm - **Spread:** 30-100 cm - **Flower Size:** 1.5-2.5 cm - **Bloom Season:** Summer - **Edible:** No - **Toxicity:** Mild - **Lifecycle:** Perennial - **Pollination Method:** Insect ## Ecological connections - **Pollinates:** honey bee (*Apis mellifera*) — Gathers nectar and pollen from its flowers. - **Pollinates:** two-form bumble bee (*Bombus bifarius*) — Visits flowers for nectar, aiding reproduction. - **Eaten by:** [lesser knapweed flower weevil](https://www.snappit.app/explore/lesser-knapweed-flower-weevil) (*Larinus minutus*) — Larvae feed on seeds within the flower heads. - **Eaten by:** banded knapweed seed head fly (*Urophora quadrifasciata*) — Larvae develop inside seeds, reducing seed production. ## Traits - [Spotted](https://www.snappit.app/explore/traits/spotted): Marked with spots or patches of a different color. - [Flowering](https://www.snappit.app/explore/traits/flowering): Flowering plants are any plants that produce flowers as part of their reproductive cycle. - [Summer Blooming](https://www.snappit.app/explore/traits/summer-blooming): Summer blooming plants produce their flowers during the summer season, often providing vibrant color when many other plants have finished. - [Grassland](https://www.snappit.app/explore/traits/grassland): Grassland habitats are terrestrial biomes dominated by grasses and herbaceous plants, supporting a variety of grazing animals. - [Pollinator Magnet](https://www.snappit.app/explore/traits/pollinator-magnet): Describes plants that are particularly attractive and beneficial to a wide range of pollinating organisms. - [Rapid Growing](https://www.snappit.app/explore/traits/rapid-growing): Rapid growing plants exhibit accelerated growth rates, quickly increasing in size and biomass within a short period. - [Invasive](https://www.snappit.app/explore/traits/invasive): Invasive species are non-native organisms that cause harm to the environment, economy, or human health. ## Collections - [Plants](https://www.snappit.app/explore/collections/plants) ## Safety **Danger:** 1/5 · Very low If you see this plant, it's best to look but not touch, as some plants can be tricky. ## Frequently Asked Questions ### How to identify spotted knapweed? Start with the whole plant, then compare leaf arrangement, leaf edges, stems and any flowers or fruit. Opposite leaves grow in pairs; alternate leaves come one at a time along the stem. These details tell you far more together than a single green leaf does. Plant Identifier: upload a photo and compare the visible details. ### How tall is spotted knapweed? 30-150 cm ### How wide does spotted knapweed spread? 30-100 cm ### How big are the flowers on spotted knapweed? 1.5-2.5 cm ### When does spotted knapweed bloom? Summer ### Is spotted knapweed edible? No ### Is spotted knapweed toxic? Mild ### What is spotted knapweed's lifecycle? Perennial ## Where to spot - [Albany Pine Bush](https://www.snappit.app/guides/places/albany-pine-bush) — New York, US · Nature Reserve - [Mormon Row Historic District](https://www.snappit.app/guides/places/mormon-row-historic-district) — Wyoming, US · Historic District - [North Entrance Road Historic District](https://www.snappit.app/guides/places/north-entrance-road-historic-district) — Wyoming, US · Historic District - [Sherburne Ranger Station Historic District](https://www.snappit.app/guides/places/sherburne-ranger-station-historic-district) — Montana, US · Historic District - [Bromley Rock Provincial Park](https://www.snappit.app/guides/places/bromley-rock-provincial-park) — British Columbia, CA · State Park - [Belleplain State Forest](https://www.snappit.app/guides/places/belleplain-state-forest) — New Jersey, US · Forest [View all places to see spotted knapweed](https://www.snappit.app/guides/where-to-see/spotted-knapweed) ## More Plants - [white snakeroot](https://www.snappit.app/explore/white-snakeroot) (*Ageratina altissima*) - [tree-of-heaven](https://www.snappit.app/explore/tree-of-heaven) (*Ailanthus altissima*) - [western sword fern](https://www.snappit.app/explore/western-sword-fern) (*Polystichum munitum*) - [common milkweed](https://www.snappit.app/explore/common-milkweed) (*Asclepias syriaca*) --- Source: [Spotted Knapweed: Facts & Places to See — Snappit](https://www.snappit.app/explore/spotted-knapweed)