Learn to use this field guide

Colorado Plants & Practical Care is an illustrated reference to garden weeds and wild plants found in Colorado. Use it to compare what plants look like and read sourced information about their effects on people, animals and local habitats. A plant profile is simply a page about one plant, with photographs, descriptions and links to the sources.

Colorado Plants & Practical Care, the bot in BoodleBox, is your tutor for using this website. It explains where to click, what the page sections mean and how to discuss what you read. You can learn the site without knowing any plant names or having a plant to identify.

Meet the two examples

We will visit Russian thistle first, then showy milkweed. These are reference examples for learning the site; you do not need either plant in your yard.

1. Russian thistle: recognize a tumbleweed

A widespread introduced weed that dries into a tumbleweed. We will use our Russian thistle page to practice searching, compare the photographs with Recognize, and read Plants & habitat to learn how it spreads.

2. Showy milkweed: check pet hazards

Its pink flowers make an appealing second example. Our Showy milkweed page has a Dogs & cats section explaining the pet warning and its limits. Milkweeds are toxic to dogs and cats; the warning covers milkweeds as a group. The original ASPCA reference is available on that plant page.

Read more in our guide: Russian thistle · Showy milkweed. Each plant page includes the evidence, original references and full photo credits.

Now open the plant library

Open the plant library, then tell the bot ready. Keep using the same BoodleBox conversation. If you have not opened the tutor yet, open Colorado Plants & Practical Care and choose Start New Chat.

The tutor will guide you through these steps, one at a time:

1. Find a familiar weed. Search for Russian thistle, a widespread tumbleweed. Use its photographs and the Recognize and Plants & habitat sections to learn what a plant page can tell you.
2. Check a flower’s pet warning. Next, search for showy milkweed. Read Dogs & cats on its plant page to understand the warning and its evidence. Original sources are there if you want more detail; opening them is optional.
3. Discuss what you learned. Later, return here to prepare a short practice message called a note. Put it in BoodleBox, review it and press Send. The tutor can then discuss your takeaway or answer your question.

Start with the library; the note form below is for that later step. Selecting a reference plant is not a confirmed identification of a plant outdoors.

Later in the tour: prepare a note for BoodleBox

Colorado Plants & Practical Care ↗
The BoodleBox tutor that walks you through this website.

Write a note about a plant

A note is a short message you prepare here and discuss with the bot. Choose a profile you have looked at, or leave it unselected, and describe your own observations below. If this is your first visit, begin with the plant library above.

What kind of note?My plant observationsTutorial practice — learning the website A possible matchI’m not sure yetAbsinth wormwood — Artemisia absinthiumAfrican rue — Peganum harmalaAnnual sowthistle — Sonchus oleraceusBig sagebrush — Artemisia tridentataBittersweet nightshade — Solanum dulcamaraBlack greasewood — Sarcobatus vermiculatusBlack henbane — Hyoscyamus nigerBlanketflower — Gaillardia aristataBohemian knotweed — Reynoutria × bohemicaBouncingbet — Saponaria officinalisBroom snakeweed — Gutierrezia sarothraeBuffalobur — Solanum rostratumBulbous bluegrass — Poa bulbosaBull thistle — Cirsium vulgareCamelthorn — Alhagi maurorumCanada goldenrod — Solidago canadensisCanada thistle — Cirsium arvenseCatchweed bedstraw — Galium aparineCatmint — Nepeta × faasseniiCheatgrass / downy brome — Bromus tectorumChicory — Cichorium intybusChinese clematis — Clematis orientalisCommon St. Johnswort — Hypericum perforatumCommon blue violet — Viola sororiaCommon burdock — Arctium minusCommon chickweed — Stellaria mediaCommon cocklebur — Xanthium strumariumCommon crupina — Crupina vulgarisCommon dandelion — Taraxacum officinaleCommon lambsquarters — Chenopodium albumCommon mallow — Malva neglectaCommon mullein — Verbascum thapsusCommon purslane — Portulaca oleraceaCommon ragweed — Ambrosia artemisiifoliaCommon sunflower — Helianthus annuusCommon tansy — Tanacetum vulgareCommon teasel — Dipsacus fullonumCommon yarrow — Achillea millefoliumCreeping woodsorrel — Oxalis corniculataCrownvetch — Securigera variaCurly dock — Rumex crispusCurlycup gumweed — Grindelia squarrosaCutleaf teasel — Dipsacus laciniatusCypress spurge — Euphorbia cyparissiasDalmatian toadflax — Linaria dalmaticaDame’s rocket — Hesperis matronalisDiffuse knapweed — Centaurea diffusaDyer’s woad — Isatis tinctoriaElongated mustard — Brassica elongataEurasian watermilfoil — Myriophyllum spicatumFernleaf yarrow — Achillea filipendulinaField bindweed — Convolvulus arvensisFlowering rush — Butomus umbellatusFoxtail barley — Hordeum jubatumFringed sage — Artemisia frigidaGiant knotweed — Reynoutria sachalinensisGiant ragweed — Ambrosia trifidaGiant reed — Arundo donaxGiant salvinia — Salvinia molestaGolden banner — Thermopsis divaricarpaGreen foxtail — Setaria viridisHairy willow-herb — Epilobium hirsutumHalogeton — Halogeton glomeratusHemp dogbane — Apocynum cannabinumHenbit — Lamium amplexicauleHoary cress — Lepidium drabaHorseweed — Erigeron canadensisHoundstongue — Cynoglossum officinaleHydrilla — Hydrilla verticillataJapanese knotweed — Reynoutria japonicaJimsonweed — Datura stramoniumJohnsongrass — Sorghum halepenseJointed goatgrass — Aegilops cylindricaKochia — Bassia scopariaLamb’s-ear — Stachys byzantinaLarge crabgrass — Digitaria sanguinalisLeafy spurge — Euphorbia esulaLewis blue flax — Linum lewisiiLow larkspur — Delphinium nuttallianumMayweed chamomile — Anthemis cotulaMeadow death camas — Toxicoscordion venenosumMeadow knapweed — Centaurea × moncktoniiMediterranean sage — Salvia aethiopisMedusahead — Taeniatherum caput-medusaeMoth mullein — Verbascum blattariaMusk thistle — Carduus nutansMyrtle spurge — Euphorbia myrsinitesNarrow-leaved Dalmatian toadflax — Linaria genistifoliaNetseed lambsquarters — Chenopodium berlandieriOrange hawkweed — Pilosella aurantiacaOxeye daisy — Leucanthemum vulgareParrotfeather — Myriophyllum aquaticumPerennial pepperweed — Lepidium latifoliumPerennial sowthistle — Sonchus arvensisPlains pricklypear — Opuntia polyacanthaPlumeless thistle — Carduus acanthoidesPoison hemlock — Conium maculatumPrairie sage — Artemisia ludovicianaPrickly lettuce — Lactuca serriolaPrickly sowthistle — Sonchus asperProstrate knotweed — Polygonum avicularePuncturevine / goathead — Tribulus terrestrisPurple loosestrife — Lythrum salicariaQuackgrass — Elymus repensRed valerian — Centranthus ruberRedroot pigweed — Amaranthus retroflexusRedstem filaree — Erodium cicutariumRubber rabbitbrush — Ericameria nauseosaRush skeletonweed — Chondrilla junceaRussian knapweed — Rhaponticum repensRussian olive — Elaeagnus angustifoliaRussian sage — Salvia yangiiRussian thistle — Salsola tragusScentless chamomile — Tripleurospermum inodorumScotch thistle — Onopordum acanthiumShepherd’s purse — Capsella bursa-pastorisShowy milkweed — Asclepias speciosaSiberian elm — Ulmus pumilaSilverleaf nightshade — Solanum elaeagnifoliumSnow-in-summer — Cerastium tomentosumSnow-on-the-mountain — Euphorbia marginataSoapweed yucca — Yucca glaucaSpotted knapweed — Centaurea stoebeSpotted spurge — Euphorbia maculataSpotted × diffuse knapweed hybrid — Centaurea × psammogenaSquarrose knapweed — Centaurea virgataStinging nettle — Urtica dioicaSulfur cinquefoil — Potentilla rectaTall buttercup — Ranunculus acrisTall larkspur — Delphinium barbeyiTamarisk — Tamarix ramosissimaTansy ragwort — Jacobaea vulgarisTaurian thistle — Onopordum tauricumTree of heaven — Ailanthus altissimaTumble mustard — Sisymbrium altissimumVelvetleaf — Abutilon theophrastiVentenata — Ventenata dubiaWestern poison ivy — Toxicodendron rydbergiiWestern ragweed — Ambrosia psilostachyaWestern water hemlock — Cicuta douglasiiWestern whorled milkweed — Asclepias subverticillataWhite clover — Trifolium repensWhite locoweed — Oxytropis sericeaWhite sweetclover — Melilotus albusWild caraway — Carum carviWild carrot — Daucus carotaWild parsnip — Pastinaca sativaWild proso millet — Panicum miliaceumYellow flag iris — Iris pseudacorusYellow nutsedge — Cyperus esculentusYellow starthistle — Centaurea solstitialisYellow sweetclover — Melilotus officinalisYellow toadflax — Linaria vulgarisYellow × Dalmatian toadflax hybrid — Linaria vulgaris × Linaria dalmatica

Compare with another plant (optional)No comparison yetAbsinth wormwood — Artemisia absinthiumAfrican rue — Peganum harmalaAnnual sowthistle — Sonchus oleraceusBig sagebrush — Artemisia tridentataBittersweet nightshade — Solanum dulcamaraBlack greasewood — Sarcobatus vermiculatusBlack henbane — Hyoscyamus nigerBlanketflower — Gaillardia aristataBohemian knotweed — Reynoutria × bohemicaBouncingbet — Saponaria officinalisBroom snakeweed — Gutierrezia sarothraeBuffalobur — Solanum rostratumBulbous bluegrass — Poa bulbosaBull thistle — Cirsium vulgareCamelthorn — Alhagi maurorumCanada goldenrod — Solidago canadensisCanada thistle — Cirsium arvenseCatchweed bedstraw — Galium aparineCatmint — Nepeta × faasseniiCheatgrass / downy brome — Bromus tectorumChicory — Cichorium intybusChinese clematis — Clematis orientalisCommon St. Johnswort — Hypericum perforatumCommon blue violet — Viola sororiaCommon burdock — Arctium minusCommon chickweed — Stellaria mediaCommon cocklebur — Xanthium strumariumCommon crupina — Crupina vulgarisCommon dandelion — Taraxacum officinaleCommon lambsquarters — Chenopodium albumCommon mallow — Malva neglectaCommon mullein — Verbascum thapsusCommon purslane — Portulaca oleraceaCommon ragweed — Ambrosia artemisiifoliaCommon sunflower — Helianthus annuusCommon tansy — Tanacetum vulgareCommon teasel — Dipsacus fullonumCommon yarrow — Achillea millefoliumCreeping woodsorrel — Oxalis corniculataCrownvetch — Securigera variaCurly dock — Rumex crispusCurlycup gumweed — Grindelia squarrosaCutleaf teasel — Dipsacus laciniatusCypress spurge — Euphorbia cyparissiasDalmatian toadflax — Linaria dalmaticaDame’s rocket — Hesperis matronalisDiffuse knapweed — Centaurea diffusaDyer’s woad — Isatis tinctoriaElongated mustard — Brassica elongataEurasian watermilfoil — Myriophyllum spicatumFernleaf yarrow — Achillea filipendulinaField bindweed — Convolvulus arvensisFlowering rush — Butomus umbellatusFoxtail barley — Hordeum jubatumFringed sage — Artemisia frigidaGiant knotweed — Reynoutria sachalinensisGiant ragweed — Ambrosia trifidaGiant reed — Arundo donaxGiant salvinia — Salvinia molestaGolden banner — Thermopsis divaricarpaGreen foxtail — Setaria viridisHairy willow-herb — Epilobium hirsutumHalogeton — Halogeton glomeratusHemp dogbane — Apocynum cannabinumHenbit — Lamium amplexicauleHoary cress — Lepidium drabaHorseweed — Erigeron canadensisHoundstongue — Cynoglossum officinaleHydrilla — Hydrilla verticillataJapanese knotweed — Reynoutria japonicaJimsonweed — Datura stramoniumJohnsongrass — Sorghum halepenseJointed goatgrass — Aegilops cylindricaKochia — Bassia scopariaLamb’s-ear — Stachys byzantinaLarge crabgrass — Digitaria sanguinalisLeafy spurge — Euphorbia esulaLewis blue flax — Linum lewisiiLow larkspur — Delphinium nuttallianumMayweed chamomile — Anthemis cotulaMeadow death camas — Toxicoscordion venenosumMeadow knapweed — Centaurea × moncktoniiMediterranean sage — Salvia aethiopisMedusahead — Taeniatherum caput-medusaeMoth mullein — Verbascum blattariaMusk thistle — Carduus nutansMyrtle spurge — Euphorbia myrsinitesNarrow-leaved Dalmatian toadflax — Linaria genistifoliaNetseed lambsquarters — Chenopodium berlandieriOrange hawkweed — Pilosella aurantiacaOxeye daisy — Leucanthemum vulgareParrotfeather — Myriophyllum aquaticumPerennial pepperweed — Lepidium latifoliumPerennial sowthistle — Sonchus arvensisPlains pricklypear — Opuntia polyacanthaPlumeless thistle — Carduus acanthoidesPoison hemlock — Conium maculatumPrairie sage — Artemisia ludovicianaPrickly lettuce — Lactuca serriolaPrickly sowthistle — Sonchus asperProstrate knotweed — Polygonum avicularePuncturevine / goathead — Tribulus terrestrisPurple loosestrife — Lythrum salicariaQuackgrass — Elymus repensRed valerian — Centranthus ruberRedroot pigweed — Amaranthus retroflexusRedstem filaree — Erodium cicutariumRubber rabbitbrush — Ericameria nauseosaRush skeletonweed — Chondrilla junceaRussian knapweed — Rhaponticum repensRussian olive — Elaeagnus angustifoliaRussian sage — Salvia yangiiRussian thistle — Salsola tragusScentless chamomile — Tripleurospermum inodorumScotch thistle — Onopordum acanthiumShepherd’s purse — Capsella bursa-pastorisShowy milkweed — Asclepias speciosaSiberian elm — Ulmus pumilaSilverleaf nightshade — Solanum elaeagnifoliumSnow-in-summer — Cerastium tomentosumSnow-on-the-mountain — Euphorbia marginataSoapweed yucca — Yucca glaucaSpotted knapweed — Centaurea stoebeSpotted spurge — Euphorbia maculataSpotted × diffuse knapweed hybrid — Centaurea × psammogenaSquarrose knapweed — Centaurea virgataStinging nettle — Urtica dioicaSulfur cinquefoil — Potentilla rectaTall buttercup — Ranunculus acrisTall larkspur — Delphinium barbeyiTamarisk — Tamarix ramosissimaTansy ragwort — Jacobaea vulgarisTaurian thistle — Onopordum tauricumTree of heaven — Ailanthus altissimaTumble mustard — Sisymbrium altissimumVelvetleaf — Abutilon theophrastiVentenata — Ventenata dubiaWestern poison ivy — Toxicodendron rydbergiiWestern ragweed — Ambrosia psilostachyaWestern water hemlock — Cicuta douglasiiWestern whorled milkweed — Asclepias subverticillataWhite clover — Trifolium repensWhite locoweed — Oxytropis sericeaWhite sweetclover — Melilotus albusWild caraway — Carum carviWild carrot — Daucus carotaWild parsnip — Pastinaca sativaWild proso millet — Panicum miliaceumYellow flag iris — Iris pseudacorusYellow nutsedge — Cyperus esculentusYellow starthistle — Centaurea solstitialisYellow sweetclover — Melilotus officinalisYellow toadflax — Linaria vulgarisYellow × Dalmatian toadflax hybrid — Linaria vulgaris × Linaria dalmatica What would you like help with?Compare identifying featuresUnderstand risks to people or animalsUnderstand habitat and ecological effectsPrepare questions about removal or management General setting (optional; no street address needed)

What can you see?

A selected profile is a candidate, not a confirmed identification. Observe without tasting or handling an unfamiliar plant.

Prepare my field note →

For a suspected poisoning, use the exposure and safety guide immediately.

What is shared?

Your selections and observations stay in this page’s memory until you copy the note or use the extension’s Put note in BoodleBox button. That button prepares a draft; pressing Send shares it with BoodleBox. The guide does not receive later clicks automatically. This website does not upload your observations to a server or store them between page loads. Reloading loses unsent observations.

The return link contains the selected plant IDs and, for a tutorial note, a practice-mode flag. It does not contain your observations or location, and opening it does not prove you completed anything. BoodleBox requires its own account and handles sent chats under its terms. This independent field guide is not operated by BoodleBox.

Content revised 2026-09-21 19:48:00Z · Source checks dated separately in the references.