# wavyleaf thistle (*Cirsium undulatum*) The wavyleaf thistle is a tall plant with wavy leaves and purple flowers. It grows in sunny places and attracts butterflies and bees, making it a lovely sight in nature. - **Category:** [Plants](https://www.snappit.app/explore/categories/plant) - **Rarity:** Common - **Danger:** 2/5 · Low - **Snaps:** 6 - **Habitat:** Grasslands ![wavyleaf thistle](https://commons.wikimedia.org/w/index.php?title=Special:Redirect/file/Cirsiumundulatum.jpg&width=800) Photo: JW Stockert, Public domain · [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Cirsiumundulatum.jpg) ## Appearance The wavyleaf thistle has tall, branching stems topped with bright purplish-pink flower heads. Its defining feature is the distinctive silvery-green leaves, which are deeply lobed, wavy, and armed with numerous sharp spines along their edges. This plant stands out with its robust, prickly appearance. ## Taxonomy - **Kingdom:** Plantae - **Phylum:** Tracheophyta - **Class:** Magnoliopsida - **Order:** Asterales - **Family:** Asteraceae - **Genus:** Cirsium ## Interesting facts - Ancient people knew how to cook and eat parts of this prickly plant, making it a surprise meal! - Each thistle flower head is actually a cluster of many tiny individual purple flowers! - Its cheerful purple flowers are a vital fuel stop for many migrating butterflies! - This plant can grow in tough, dry soils where many other plants simply cannot survive! ## Special abilities - **Spiny Defense System:** Wavyleaf thistle has sharp spines covering its leaves and stems that help it defend against hungry herbivores. - **Deep Root Anchor:** Wavyleaf thistle grows an extremely long taproot that helps it find deep water and survive dry conditions. - **Wind-Powered Seeds:** Wavyleaf thistle seeds have a fluffy pappus that helps them float on the wind for wide dispersal. ## Measurements & details - **Height:** 30-180 cm - **Spread:** 30-90 cm - **Flower Size:** 2-5 cm - **Bloom Season:** Summer - **Edible:** Yes - **Toxicity:** None - **Lifecycle:** Biennial - **Pollination Method:** Insect ## Ecological connections - **Pollinates:** Honey Bee (*Apis mellifera*) — Gathers nectar and pollen from its flowers. - **Pollinates:** [Monarch Butterfly](https://www.snappit.app/explore/monarch-butterfly) (*Danaus plexippus*) — Feeds on nectar from its vibrant blooms. - **Eaten by:** [American Goldfinch](https://www.snappit.app/explore/american-goldfinch) (*Carduelis tristis*) — Eats the plant's seeds from its mature flower heads. - **Eaten by:** Painted Lady Butterfly (*Vanessa cardui*) — Larvae sometimes feed on its leaves. ## Traits - [Flowering](https://www.snappit.app/explore/traits/flowering): Flowering plants are any plants that produce flowers as part of their reproductive cycle. - [Biennial](https://www.snappit.app/explore/traits/biennial): Biennial plants complete their life cycle over two growing seasons, typically forming foliage in the first year and flowering/seeding in the second. - [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. - [Colorful](https://www.snappit.app/explore/traits/colorful): Colorful describes organisms or objects displaying a wide range of bright and distinct colors. - [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. - [Spiky/Thorny](https://www.snappit.app/explore/traits/spiky-thorny): Possessing sharp, pointed projections or spines on the body or surface. ## Collections - [Plants](https://www.snappit.app/explore/collections/plants) ## Safety **Danger:** 2/5 · Low Be careful around thistles, as their leaves can be sharp! ## Frequently Asked Questions ### How to identify wavyleaf thistle? 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 wavyleaf thistle? 30-180 cm ### How wide does wavyleaf thistle spread? 30-90 cm ### How big are the flowers on wavyleaf thistle? 2-5 cm ### When does wavyleaf thistle bloom? Summer ### Is wavyleaf thistle edible? Yes ### Is wavyleaf thistle toxic? None ### What is wavyleaf thistle's lifecycle? Biennial ## Where to spot - [Dinosaur Ridge](https://www.snappit.app/guides/places/dinosaur-ridge) — Colorado, US · Natural Landmark - [Quartz Mountain Nature Park](https://www.snappit.app/guides/places/quartz-mountain-nature-park) — Oklahoma, US · Park - [Bertrand F. Harrison Arboretum](https://www.snappit.app/guides/places/bertrand-f-harrison-arboretum) — Utah, US · Botanical Garden - [Fort George Wright](https://www.snappit.app/guides/places/fort-george-wright) — Washington, US · Historic Site - [Lake Brownwood State Park](https://www.snappit.app/guides/places/lake-brownwood-state-park) — Texas, US · State Park - [Provo City Library](https://www.snappit.app/guides/places/provo-city-library) — Utah, US · Historic District [View all places to see wavyleaf thistle](https://www.snappit.app/guides/where-to-see/wavyleaf-thistle) ## 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: [Wavyleaf Thistle: Facts & Places to See — Snappit](https://www.snappit.app/explore/wavyleaf-thistle)