Cutleaf teasel
Discuss this plant with the guide — choose this profile as a possible match and prepare your observations for Colorado Plants & Practical Care.
Dipsacus laciniatus
Colorado noxious weed · List B — Stop the spread. CO-rules-2025
Established in some areas. Requirements vary by location: eradication, containment or suppression to stop further spread. This is a management category, separate from danger ratings. Category source · What the lists mean.
Prickly stands can displace native vegetation. Exposure help.
Identification caveat: Common teasel usually has unlobed leaves and lavender flowers. Flower color alone does not establish the species.
Still researching this plant
This is a sourced working profile. Evidence is incomplete for Dogs & cats, Other animals. Identification and source-photo limits are explained below. Independent botanical and veterinary review is pending. Uncertainty is not a finding that the plant is safe.
Three views of this plant
Source-identified reference photographs; these are not a complete identification key. A source location outside Colorado does not establish local occurrence.
Alexander Klink · CC BY 3.0
Photo source and identification
Original record · Original image
Source-identified photograph with visual consistency check Dipsacus laciniatus L. Source labeling and visible consistency checked; not an independent specimen determination.
Wikimedia-generated thumbnail rescaling only; downloaded bytes unchanged. Gallery display preserves the full image; the catalog preview uses a CSS crop.
Alex Abair · CC BY 4.0
Photo source and identification
Original record · Original image
Source-identified photograph with visual consistency check Cutleaf teasel ( Dipsacus laciniatus ) in the United States Source labeling and visible consistency checked; not an independent specimen determination.
Wikimedia-generated thumbnail rescaling only; downloaded bytes unchanged. Gallery display preserves the full image; the catalog preview uses a CSS crop.
Stefan.lefnaer · CC BY-SA 4.0
Photo source and identification
Original record · Original image
Source-identified photograph with visual consistency check Capitulum (detail) Taxonym: Dipsacus laciniatus ss Fischer et al. EfÖLS 2008 ISBN 978-3-85474-187-9 Location: Marchfeldkanal near Groß-Jedlersdorf, Wien-Floridsdorf - ca. 160 m a.s.l. Habitat: fallow land Source labeling and visible consistency checked; not an independent specimen determination.
Wikimedia-generated thumbnail rescaling only; downloaded bytes unchanged. Gallery display preserves the full image; the catalog preview uses a CSS crop.
Recognize
Deeply cut, opposite leaves clasp the stem; generally white flowers open on prickly, elongated heads. F-teasels
Plants & habitat
Reported near Denver. Dense stands can threaten meadow and wetland vegetation; impacts vary among sites. F-teasels
People
Prickles on stems and heads make unprotected handling a puncture concern. F-teasels
Evidence scope: Physical-risk inference.
Dogs & cats
Prickly plants present a contact hazard; the reviewed source does not establish pet ingestion effects. F-teasels
Evidence scope: Physical-risk inference; ingestion evidence gap.
Other animals
The reviewed sources do not establish species-specific ingestion effects or a safe exposure amount for livestock. Missing evidence does not establish safety.
Before taking action
Confirm identification and the requirements of your county weed program. For chemical treatment, follow the current product label, including restrictions around animals and water. S27
References
- CO-rules-2025 — Colorado Noxious Weed Act rules, 8 CCR 1206-2, Colorado Secretary of State / Department of Agriculture. Accessed 2026-09-07T01:07:48+00:00. Locator: Parts 3.1, 4.1, 5.1; management provisions; effective May 15, 2025.
- F-teasels — Fuller’s and cutleaf teasel, USDA Forest Service. Accessed 2026-09-07T01:34:00+00:00. Locator: Species descriptions, occurrence and hazard sections; food preparation and treatment instructions not adopted.
- S27 — 2103 – Colorado Noxious Weeds, PlantTalk Colorado · CSU Extension. Accessed 2026-09-07T00:23:57+00:00. Locator: List A, B and C management categories.