Weed identification · Free tool · United States
What weed is this?
Answer four quick questions about where it’s growing, what kind of plant it is, its flower color and any giveaway features. We’ll narrow 215 US weeds down to the few it could be, with a photo and the one thing to check.
Start with the plant type and flower color, then check for a giveaway: milky sap when you break a leaf, leaves in threes like clover, spines or burs, or a strong smell when you crush it. Those four features alone narrow most weeds to a handful. Every match links to a full fact sheet with look-alikes and control tips. Checked Nov. 14, 2026.
Identify your weed
Answer any question to see matches.
Skip any question you’re unsure of. Not blooming? Leave flower color blank. Still stuck? Send us a photo and we’ll email you back with what it is.
Lawn weeds with yellow flowers
Bird’s-foot Trefoil, Black Medic, Burclover, Common Purslane, Creeping Buttercup, Creeping Woodsorrel, Dandelion, Large Hop Clover, Lesser Celandine, London Rocket, Mock Strawberry, Orange Hawkweed, Oxeye Daisy, Pineappleweed, Puncturevine (Goathead), Yellow Wood Sorrel.
Lawn weeds with purple, pink or blue flowers
Bull Thistle, Canada Thistle, Chicory, Common Lespedeza, Common Mallow, Corn Speedwell, Creeping Charlie (Ground Ivy), Creeping Speedwell, Florida Beggarweed, Florida Betony, Heal-all, Henbit, Horsenettle, Ivyleaf Speedwell, Little Mallow (Cheeseweed), Purple Cudweed, Purple Deadnettle, Red Sorrel, Redstem Filaree, Wild Violet.
Lawn weeds with white flowers
Buckhorn Plantain, Carpetweed, Common Chickweed, Common Lespedeza, Common Mallow, Dollarweed, Florida Betony, Florida Pusley, Hairy Bittercress, Horsenettle, Khakiweed, Little Mallow (Cheeseweed), Mouse-ear Chickweed, Oxeye Daisy, Prostrate Knotweed, Purple Cudweed, Shepherd’s Purse, Virginia Buttonweed, White Clover, Wild Violet, Yarrow.
Grass-like weeds in lawns
Annual Bluegrass, Bahiagrass, Bermudagrass, Cogongrass, Creeping Bentgrass, Dallisgrass, Doveweed, Field Sandbur, Goosegrass, Green Foxtail, Green Kyllinga, Italian Ryegrass, Japanese Stiltgrass, Large Crabgrass, Nimblewill, Purple Nutsedge, Quackgrass, Smooth Crabgrass, Smutgrass, Southern Crabgrass, Star-of-Bethlehem, Tall Fescue (Clumps in Lawns), Torpedograss, Wavyleaf Basketgrass, Wild Garlic, Wild Onion, Yellow Foxtail, Yellow Nutsedge. Sedges have triangular stems, and wild onion and wild garlic smell like onion when crushed; true grasses have neither.
Weeds with leaves in threes (look like clover)
Atlantic Poison Oak, Bermuda Buttercup, Bird’s-foot Trefoil, Black Medic, Burclover, Common Lespedeza, Creeping Buttercup, Creeping Woodsorrel, Florida Beggarweed, Kudzu, Large Hop Clover, Mock Strawberry, Pacific Poison Oak, Poison Ivy, Scotch Broom, Sericea Lespedeza, White Clover, Yellow Sweetclover, Yellow Wood Sorrel. Poison ivy and poison oak are woody vines or shrubs with three leaflets; don’t touch them bare-handed.
Weeds with milky sap
Annual Sowthistle, Chicory, Dandelion, Hemp Dogbane, Leafy Spurge, Orange Hawkweed, Perennial Sowthistle, Prickly Lettuce, Spiny Sowthistle, Spotted Spurge.
Prickly, spiny and burry weeds
Autumn Olive, Buffalobur, Bull Thistle, Bur Cucumber, Burclover, Callery Pear, Canada Thistle, Catchweed Bedstraw, Common Buckthorn, Common Burdock, Common Cocklebur, Common Greenbrier, Diffuse Knapweed, Downy Brome (Cheatgrass), Field Sandbur, Florida Beggarweed, Foxtail Barley, Himalayan Blackberry, Horsenettle, Houndstongue, Japanese Barberry, Japanese Hops, Jimsonweed, Khakiweed, Lawn Burweed, Medusahead, Mile-a-Minute Vine, Multiflora Rose, Musk Thistle, Perennial Sowthistle, Plumeless Thistle, Prickly Lettuce, Prickly Sida, Puncturevine (Goathead), Redstem Filaree, Russian Thistle (Tumbleweed), Scotch Thistle, Silverleaf Nightshade, Spiny Amaranth, Spiny Sowthistle, Stinging Nettle, Teasel, Tropical Soda Apple, Wavyleaf Basketgrass, Yellow Starthistle.
Weeds with a strong smell when crushed
Bittersweet Nightshade, Brazilian Peppertree, Common Tansy, Creeping Charlie (Ground Ivy), Field Pennycress, Garlic Mustard, Jimsonweed, Mugwort, Perennial Pepperweed, Pineappleweed, Poison Hemlock, Queen Anne’s Lace (Wild Carrot), Sicklepod, Tree-of-Heaven, Velvetleaf, Wild Garlic, Wild Onion, Yarrow.
Weedy vines
Air Potato, Bittersweet Nightshade, Black Swallow-wort, Bur Cucumber, Chinese Wisteria, Common Greenbrier, English Ivy, Field Bindweed, Field Dodder, Hedge Bindweed, Ivyleaf Morningglory, Japanese Honeysuckle, Japanese Hops, Kudzu, Mile-a-Minute Vine, Oriental Bittersweet, Pacific Poison Oak, Pale Swallow-Wort, Pitted Morningglory, Poison Ivy, Porcelain Berry, Tall Morningglory, Trumpet Creeper, Virginia Creeper, Wild Buckwheat.
Weeds that are toxic or can burn skin
Atlantic Poison Oak, Bermuda Buttercup, Bittersweet Nightshade, Brazilian Peppertree, Buffalobur, Chinese Privet, Chinese Wisteria, Common Cocklebur, Common Groundsel, Common St. John’s Wort, Common Tansy, Creeping Buttercup, Creeping Woodsorrel, Dallisgrass, Eastern Black Nightshade, English Ivy, Field Horsetail, Giant Hogweed, Hemp Dogbane, Hoary Cress (Whitetop), Horsenettle, Houndstongue, Japanese Barberry, Japanese Hops, Jimsonweed, Kochia, Leafy Spurge, Lesser Celandine, Little Mallow (Cheeseweed), Pacific Poison Oak, Pale Swallow-Wort, Pitted Morningglory, Poison Hemlock, Poison Ivy, Poison Sumac, Pokeweed, Puncturevine (Goathead), Queen Anne’s Lace (Wild Carrot), Russian Knapweed, Russian Thistle (Tumbleweed), Scotch Broom, Sicklepod, Silverleaf Nightshade, Smooth Pigweed, Spiny Amaranth, Spotted Spurge, Star-of-Bethlehem, Stinging Nettle, Tall Morningglory, Tansy Ragwort, Tree-of-Heaven, Tropical Soda Apple, Trumpet Creeper, Virginia Copperleaf, Virginia Creeper, Wild Chervil, Wild Parsnip, Yellow Flag Iris, Yellow Starthistle. Each page says what to watch for and how to handle it safely.
Questions
What is this weed with yellow flowers in my lawn?
The usual suspects in US lawns: Bird’s-foot Trefoil, Black Medic, Burclover, Common Purslane, Creeping Buttercup, Creeping Woodsorrel, Dandelion, Large Hop Clover, Lesser Celandine, London Rocket, Mock Strawberry, Orange Hawkweed, Oxeye Daisy, Pineappleweed, Puncturevine (Goathead), Yellow Wood Sorrel. Check for milky sap (dandelion), leaves in threes (clovers, black medic, wood sorrel, mock strawberry) or a fleshy, reddish stem lying flat (purslane).
What weed looks like grass but isn’t?
Yellow nutsedge, wild onion, wild garlic and star-of-Bethlehem all have grass-like leaves. Nutsedge has a triangular stem; wild onion and wild garlic smell like onion when crushed; star-of-Bethlehem has a white stripe down each leaf and no onion smell.
Which weeds have milky sap?
Of the weeds in our guide: Annual Sowthistle, Chicory, Dandelion, Hemp Dogbane, Leafy Spurge, Orange Hawkweed, Perennial Sowthistle, Prickly Lettuce, Spiny Sowthistle, Spotted Spurge. Spotted spurge is the one that grows flat in a lawn, and leafy spurge stands upright with yellow-green bracts. The rest have yellow, orange or blue flowers, except hemp dogbane.
Which weeds look like clover?
Atlantic Poison Oak, Bermuda Buttercup, Bird’s-foot Trefoil, Black Medic, Burclover, Common Lespedeza, Creeping Buttercup, Creeping Woodsorrel, Florida Beggarweed, Kudzu, Large Hop Clover, Mock Strawberry, Pacific Poison Oak, Poison Ivy, Scotch Broom, Sericea Lespedeza, White Clover, Yellow Sweetclover, Yellow Wood Sorrel all have leaves in threes. That includes poison ivy and both poison oaks, so check before you pull anything with three leaflets.
How do I get rid of the weed once I know what it is?
Open its fact sheet. Each page has what it’s confused with, the best time to act, and pulling, mowing and herbicide options.
Sources: traits come from the fact sheets in our weed identification guide, which cite Penn State Extension, the USDA PLANTS Database, state noxious weed lists and other university extension sources. Photos: Wikimedia Commons contributors, credited under each result and on each weed’s page. Checked Nov. 14, 2026.
Muthler Landscaping & Construction · Lock Haven, PA
Can’t tell what it is?
Snap a photo and send it. We’ll email you back with what it is and how to get rid of it. If you’re in central PA and it’s part of a bigger mess, we can fix that too.
Send us a photoAll 215 weedsAlso: hardiness zone by ZIP, Pennsylvania frost dates by town, noxious weed laws by state.
Muthler Landscaping & Construction LLC · 913 Bellefonte Ave, Lock Haven, PA 17745 · (570) 397-9800 · PA HIC #PA212584. Herbicides: always read and follow the label.