Narrow-leaved Dalmatian toadflax

Discuss this plant with the guide — choose this profile as a possible match and prepare your observations for Colorado Plants & Practical Care.

Linaria genistifolia

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.

Listed taxon with difficult identification. Exposure help.

Identification caveat: Colorado’s listing name is retained. Drought-stressed L. dalmatica and hybrid toadflaxes can also have narrow leaves. Photographs from Europe show source-identified L. genistifolia; they do not confirm Colorado occurrence. Expert identification is needed before assigning a local plant to this taxon.

Still researching this plant

This is a sourced working profile. Evidence is incomplete for People, 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.

**flowers** — Side view of yellow toadflax flowers and their long spurs beside developing reproductive structures, with a 10 mm scale.
Stefan.lefnaer · CC BY-SA 4.0
Photo source and identification
Original record · Original image
Source-identified photograph with visual consistency check Inflorescence Taxonym: Linaria genistifolia (subsp. genistifolia) ss Fischer et al. EfÖLS 2008 ISBN 978-3-85474-187-9 Location: Schmetterlingswiese in Donaupark, Vienna-Donaustadt - ca. 160 m a.s.l. Habitat: sandy area 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.

**leaves and stem** — Smooth, lance-shaped leaves along an upright toadflax stem, viewed against the sky.
Stefan.lefnaer · CC BY-SA 4.0
Photo source and identification
Original record · Original image
Source-identified photograph with visual consistency check Stem with leaves Taxonym: Linaria genistifolia (subsp. genistifolia) ss Fischer et al. EfÖLS 2008 ISBN 978-3-85474-187-9 Location: Steinberg near Ernstbrunn, district Korneuburg, Lower Austria - ca. 450 m a.s.l. Habitat: semi-dry grassland 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.

**habit** — Tall, slender, branching toadflax plant rising above surrounding grassland vegetation.
Stefan.lefnaer · CC BY-SA 4.0
Photo source and identification
Original record · Original image
Source-identified photograph with visual consistency check Habitus Taxonym: Linaria genistifolia (subsp. genistifolia) ss Fischer et al. EfÖLS 2008 ISBN 978-3-85474-187-9 Location: Wolfseck km northeast of Ladendorf, district Mistelbach, Lower Austria - ca. 240 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

The federal guide distinguishes L. genistifolia by smaller flowers and capsules; narrow leaves alone are unreliable. F-toadflaxes

Plants & habitat

Colorado lists this taxon separately. The 2016 federal guide considered its North American distribution unconfirmed, so a state listing is not proof of a local population. F-toadflaxes CO-rules-2025

Evidence scope: Regulatory listing and historical taxonomic uncertainty.

People

The reviewed sources do not establish species-specific ingestion effects or a safe exposure amount for people. Missing evidence does not establish safety.

Dogs & cats

The reviewed sources do not establish species-specific ingestion effects or a safe exposure amount for dogs or cats. Missing evidence does not establish safety.

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-toadflaxes — Biology and Biological Control of Dalmatian and Yellow Toadflax, USDA Forest Service. Accessed 2026-09-07T01:19:10+00:00. Locator: Species or hybrid identity, description and ecology.
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.

Content revised 2026-09-07 03:50:00Z · Source checks dated separately in the references.