Yellow × Dalmatian toadflax hybrid
Discuss this plant with the guide — choose this profile as a possible match and prepare your observations for Colorado Plants & Practical Care.
Linaria vulgaris × Linaria dalmatica
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.
Variable hybrid; persistent spreading roots. Exposure help.
Identification caveat: Reference photos are identified hybrids in a USDA Forest Service manual. The third, flower-detail image is small because the original source is only 176 × 329 pixels; it has not been enlarged to imply more detail.
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.
Sharlene E. Sing, USDA Forest Service, Rocky Mountain Research Station · Public domain (U.S. federal employee work)
Photo source and identification
Original record · Original image
Explicit federal publication identification of the requested hybrid Printed page 28 explicitly defines hybrid toadflax as Linaria vulgaris × L. dalmatica / L. dalmatica × L. vulgaris. The caption to Figure 22b explicitly identifies the selected panel as hybrid toadflax. Hybrid identity follows the publication; no independent genetic determination was performed.
None: original embedded JPEG byte stream extracted from PDF, not a rendered or cropped page. Gallery display preserves the full image; the catalog preview uses a CSS crop.
Sharlene E. Sing, USDA Forest Service, Rocky Mountain Research Station · Public domain (U.S. federal employee work)
Photo source and identification
Original record · Original image
Explicit federal publication identification of the requested hybrid Printed page 28 explicitly defines hybrid toadflax as Linaria vulgaris × L. dalmatica / L. dalmatica × L. vulgaris. The caption to Figure 22c explicitly identifies the selected panel as hybrid toadflax. Hybrid identity follows the publication; no independent genetic determination was performed.
None: original embedded JPEG byte stream extracted from PDF, not a rendered or cropped page. Gallery display preserves the full image; the catalog preview uses a CSS crop.
Sharlene E. Sing, USDA Forest Service, Rocky Mountain Research Station · Public domain (U.S. federal employee work)
Photo source and identification
Original record · Original image
Explicit federal publication identification of the requested hybrid Printed page 28 explicitly defines hybrid toadflax as Linaria vulgaris × L. dalmatica / L. dalmatica × L. vulgaris. The caption to Figure 24e explicitly identifies the selected panel as hybrid toadflax. Hybrid identity follows the publication; no independent genetic determination was performed. The only independently photographed federal hybrid flower panel located in this guide is 176×329 pixels. It is retained as a clearly flagged small reference; it does not meet the requested 960–1280-pixel target and was not upscaled.
None: original embedded JPEG byte stream extracted from PDF, not a rendered or cropped page. Gallery display preserves the full image; the catalog preview uses a CSS crop.
Recognize
Yellow spurred flowers and variable leaves may combine parental traits; leaf width and flower color alone cannot confirm a hybrid. F-toadflaxes
Plants & habitat
Perennial hybrids spread through root buds and seeds. The federal guide reports vigorous growth and competitive potential in disturbed habitats. F-toadflaxes
Evidence scope: Hybrid-group evidence; performance varies.
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.