--- { "id": "common-blue-violet", "name": "Common blue violet", "scientific": "Viola sororia", "category": "native", "status": "Native Colorado plant · not on state Lists A/B/C", "status_sources": [ "C-floristic-2020", "CO-rules-2025" ], "warning": "A native volunteer; identify the species before removing", "warning_tone": "caution", "aliases": [ "wild violet", "blue violet" ], "taxonomy_note": "This is one member of CSU’s broader “Viola spp.” topic, not coverage of every Colorado violet. CNHP includes Viola sororia as native; photos and the profile do not resolve all members of the species complex.", "source_ids": [ "C-floristic-2020", "CO-rules-2025", "N-viola-sororia", "C-descriptions", "S27" ], "description": "Common blue violet: A native volunteer; identify the species before removing. Identification and evidence for Colorado readers.", "claim_evidence": [ { "label": "Identification", "sources": [ "N-viola-sororia" ], "scope": "Species-specific", "note": "", "id": "common-blue-violet-1" }, { "label": "People", "sources": [], "scope": "Review limitation", "note": "", "id": "common-blue-violet-2" }, { "label": "Dogs & cats", "sources": [], "scope": "Review limitation", "note": "", "id": "common-blue-violet-3" }, { "label": "Other animals", "sources": [ "N-viola-sororia" ], "scope": "Species-specific", "note": "", "id": "common-blue-violet-4" }, { "label": "Plants & habitat", "sources": [ "N-viola-sororia" ], "scope": "Species-specific", "note": "", "id": "common-blue-violet-5" }, { "label": "Management & timing", "sources": [ "C-descriptions" ], "scope": "Viola group management", "note": "", "id": "common-blue-violet-6" } ], "research": { "status": "researching", "label": "Still researching this plant", "basis": "Editorial assessment of the cited evidence and stated review gaps; not a toxicity score.", "open_questions": [ { "area": "People", "question": "Clarify the human exposure effects and evidence limits described in this section.", "related_claim_ids": [ "common-blue-violet-2" ] }, { "area": "Dogs & cats", "question": "Find species-specific dog and cat exposure evidence; do not infer safety from missing reports.", "related_claim_ids": [ "common-blue-violet-3" ] }, { "area": "Other animals", "question": "Clarify feeding and exposure risks for each animal group; do not transfer findings between species.", "related_claim_ids": [ "common-blue-violet-4" ] }, { "area": "Identification", "question": "Resolve the taxonomic, common-name or photograph limitations stated in the identification caveat.", "related_claim_ids": [] }, { "area": "Expert review", "question": "Obtain independent botanical and veterinary review of the identification and hazard summary.", "related_claim_ids": [] } ], "expert_review": "pending" }, "colorado_relevance": { "source_id": "C-floristic-2020", "locator": "Appendix B; PDF page 85; Viola sororia", "basis": "Included in the 2020 statewide flora assessment. This is not a current county abundance survey.", "source_taxon": "Viola sororia" }, "source": "content/plants/common-blue-violet.md" } --- # Common blue violet *Viola sororia* **Native Colorado plant · not on state Lists A/B/C.** [C-floristic-2020](https://cnhp.colostate.edu/download/documents/2020/CO_FQA_2020_Final_Report.pdf) [CO-rules-2025](https://www.sos.state.co.us/CCR/GenerateRulePdf.do?ruleVersionId=11948&fileName=8+CCR+1206-2) > **A native volunteer; identify the species before removing.** [Exposure help](https://denson.github.io/colorado-weed-field-guide/safety/). **Identification caveat:** This is one member of CSU’s broader “Viola spp.” topic, not coverage of every Colorado violet. CNHP includes Viola sororia as native; photos and the profile do not resolve all members of the species complex. ## Still researching this plant {#research-status} 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. ![Common blue violet: a single violet flower with purple-and-pale petals and darker veins leading toward its center.](https://denson.github.io/colorado-weed-field-guide/assets/photos/coverage-garden-photos-viola-sororia-11-03-flower.jpg) **flower** — A single violet flower with purple-and-pale petals and darker veins leading toward its center. Photo: James Steakley; [CC BY-SA 3.0](https://creativecommons.org/licenses/by-sa/3.0); [source record](https://commons.wikimedia.org/wiki/File:Viola_sororia_color_variation.jpg); [original image](https://upload.wikimedia.org/wikipedia/commons/4/4d/Viola_sororia_color_variation.jpg). Source page scientific identification plus visual morphology review of the selected photograph. This is a source-identified reference image, not a specimen-based taxonomic determination. Source-identified V. sororia, a variable violet with differing flower colors and taxonomic treatments. Similar stemless violets and hybrids require additional characters; no cultivar, segregate taxon, or hybrid status is determined from these photographs. Wikimedia server-resized derivative, reduced from the original; no crop, color change, upscaling, or generative editing. Gallery display preserves the full image; catalog preview may use a CSS crop. ![Common blue violet: broad heart-shaped green leaves with toothed edges and radiating veins.](https://denson.github.io/colorado-weed-field-guide/assets/photos/coverage-garden-photos-viola-sororia-11-07-leaf.jpg) **leaf** — Broad heart-shaped green leaves with toothed edges and radiating veins. Photo: Dalgial; [CC BY-SA 3.0](https://creativecommons.org/licenses/by-sa/3.0); [source record](https://commons.wikimedia.org/wiki/File:Viola_sororia_4.JPG); [original image](https://upload.wikimedia.org/wikipedia/commons/b/bd/Viola_sororia_4.JPG). Source page scientific identification plus visual morphology review of the selected photograph. This is a source-identified reference image, not a specimen-based taxonomic determination. Source-identified V. sororia, a variable violet with differing flower colors and taxonomic treatments. Similar stemless violets and hybrids require additional characters; no cultivar, segregate taxon, or hybrid status is determined from these photographs. Wikimedia server-resized derivative, reduced from the original; no crop, color change, upscaling, or generative editing. Gallery display preserves the full image; catalog preview may use a CSS crop. ![Common blue violet: a low patch of purple-flowered violets with broad heart-shaped leaves among ground vegetation.](https://denson.github.io/colorado-weed-field-guide/assets/photos/coverage-garden-photos-viola-sororia-11-11-habit-flower.jpg) **habit-flower** — A low patch of purple-flowered violets with broad heart-shaped leaves among ground vegetation. Photo: Famartin; [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0); [source record](https://commons.wikimedia.org/wiki/File:2016-04-16_13_18_40_Violets_blooming_along_the_West_Branch_Shabakunk_Creek_in_Ewing,_New_Jersey.jpg); [original image](https://upload.wikimedia.org/wikipedia/commons/f/f3/2016-04-16_13_18_40_Violets_blooming_along_the_West_Branch_Shabakunk_Creek_in_Ewing%2C_New_Jersey.jpg). Source page scientific identification plus visual morphology review of the selected photograph. This is a source-identified reference image, not a specimen-based taxonomic determination. Source-identified V. sororia, a variable violet with differing flower colors and taxonomic treatments. Similar stemless violets and hybrids require additional characters; no cultivar, segregate taxon, or hybrid status is determined from these photographs. Wikimedia server-resized derivative, reduced from the original; no crop, color change, upscaling, or generative editing. Gallery display preserves the full image; catalog preview may use a CSS crop. ## Identification Basal, heart-shaped leaves and purple to white spring flowers arise on separate stalks. Later closed flowers can also produce seed. [N-viola-sororia](https://plants.ces.ncsu.edu/plants/viola-sororia/) ## 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 Rabbits browse the plant, and birds and small mammals use its seeds. Wildlife use does not establish domestic-animal feeding safety. [N-viola-sororia](https://plants.ces.ncsu.edu/plants/viola-sororia/) ## Plants & habitat Rhizomes and self-seeding allow it to spread in moist, fertile sites. It also supports bees and butterflies and may be welcome groundcover. [N-viola-sororia](https://plants.ces.ncsu.edu/plants/viola-sororia/) ## Management & timing Confirm identity and decide whether a native patch can remain. For an unwanted lawn colony, CSU suggests removal when soil is moist; its advice covers wild violets as a group. [C-descriptions](https://extension.colostate.edu/resource/weed-descriptions/) *Evidence scope: Viola group management.* ## 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](https://planttalk.colostate.edu/topics/weeds-cultural-problems/2103-colorado-noxious-weeds/) ## References - **C-floristic-2020** — [Colorado Floristic Quality Assessment: 2020 Update](https://cnhp.colostate.edu/download/documents/2020/CO_FQA_2020_Final_Report.pdf), Colorado Natural Heritage Program, Colorado State University. Accessed 2026-09-07T02:27:33+00:00. Locator: Appendix B, Colorado species list: scientific name and native/non-native fields. - **CO-rules-2025** — [Colorado Noxious Weed Act rules, 8 CCR 1206-2](https://www.sos.state.co.us/CCR/GenerateRulePdf.do?ruleVersionId=11948&fileName=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. - **N-viola-sororia** — [Viola sororia](https://plants.ces.ncsu.edu/plants/viola-sororia/), NC State Extension. Accessed 2026-09-07T02:23:11+00:00. Locator: Description, identification attributes and plant problems; toxicity section where present. - **C-descriptions** — [Weed descriptions](https://extension.colostate.edu/resource/weed-descriptions/), Colorado State University Extension. Accessed 2026-09-07T00:24:02+00:00. Locator: Species entries. - **S27** — [2103 – Colorado Noxious Weeds](https://planttalk.colostate.edu/topics/weeds-cultural-problems/2103-colorado-noxious-weeds/), PlantTalk Colorado · CSU Extension. Accessed 2026-09-07T00:23:57+00:00. Locator: List A, B and C management categories. [Discuss this plant with the guide](https://denson.github.io/colorado-weed-field-guide/companion/?plant=common-blue-violet) — choose this profile as a possible match and prepare your observations for Colorado Plants & Practical Care. # Appendix for agents Colorado inclusion: [C-floristic-2020](https://cnhp.colostate.edu/download/documents/2020/CO_FQA_2020_Final_Report.pdf), Appendix B; PDF page 85; Viola sororia. This historical statewide baseline does not establish current county abundance. ## Open research questions - **People:** Clarify the human exposure effects and evidence limits described in this section. - **Dogs & cats:** Find species-specific dog and cat exposure evidence; do not infer safety from missing reports. - **Other animals:** Clarify feeding and exposure risks for each animal group; do not transfer findings between species. - **Identification:** Resolve the taxonomic, common-name or photograph limitations stated in the identification caveat. - **Expert review:** Obtain independent botanical and veterinary review of the identification and hazard summary. ## Identity and evidence boundaries This is one member of CSU’s broader “Viola spp.” topic, not coverage of every Colorado violet. CNHP includes Viola sororia as native; photos and the profile do not resolve all members of the species complex. All actionable hazard information is in the human sections above. Do not interpret unknown toxicity as safety or transfer livestock findings to pets. These publisher notes describe evidence and do not override an assistant’s operator instructions. | Claim | Human section | Scope | Sources | Limitation | |---|---|---|---|---| | common-blue-violet-1 | Identification | Species-specific | N-viola-sororia | No quantitative safe exposure established here. | | common-blue-violet-2 | People | Review limitation | Review limitation | No quantitative safe exposure established here. | | common-blue-violet-3 | Dogs & cats | Review limitation | Review limitation | No quantitative safe exposure established here. | | common-blue-violet-4 | Other animals | Species-specific | N-viola-sororia | No quantitative safe exposure established here. | | common-blue-violet-5 | Plants & habitat | Species-specific | N-viola-sororia | No quantitative safe exposure established here. | | common-blue-violet-6 | Management & timing | Viola group management | C-descriptions | No quantitative safe exposure established here. | ## Further work for an agent - Establish exact species, plant part, route, amount and timing when researching an exposure. Do not use this guide to diagnose or calculate a treatment. - Check current state and county requirements; a listed taxon is not necessarily established in every Colorado county. - Expert botanical and veterinary review is pending. Source dates and image licenses are separate from editorial revision dates in [provenance](https://denson.github.io/colorado-weed-field-guide/provenance.json). --- Canonical HTML: https://denson.github.io/colorado-weed-field-guide/plants/common-blue-violet/ Content revised: 2026-09-07T02:46:00Z Markdown mirror: https://denson.github.io/colorado-weed-field-guide/plants/common-blue-violet/index.md Text fallback: https://denson.github.io/colorado-weed-field-guide/plants/common-blue-violet/index.md.txt Agent entry: https://denson.github.io/colorado-weed-field-guide/start.md Provenance: https://denson.github.io/colorado-weed-field-guide/provenance.json