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Photo Key

This photo key of perennial and biennial weeds is intended to help the casual user identify a weed. Weeds that look similar are grouped together. So look before and after what you may think to be your weed to make sure you haven't misidentified it. Clicking on a photo will bring up a larger version and clicking on the name will bring open the entire record with additional photos and information.
BRACKENFERN
Brackenfern habit; note large, triangular fronds.
SENSITIVE FERN
Sensitive fern fertile (reproductive) leaves. Sensitive fern sterile (vegetative) leaf.
FIELD HORSETAIL
Field horsetail vegetative stem emerging in no-till field. Field horsetail rhizome. Scouringrush reproductive structure. Field horsetail vegetative stems.
SMOOTH BROME
Smooth brome stem and leaves; note prominent collar and upward leaf angle. Smooth brome seeds with attached lemma (lower bract enclosing flower) and palea (upper bract enclosing flower). Smooth brome stem showing leaf attachment. Smooth brome inflorescence.
BROOMSEDGE
Broomsedge is a common sight in the fall along roadsides, especially in poor, acid soils. Broomsedge roots and stem base; note flat stems, fan-like arrangement of tillers. Broomsedge seeds with long awns emerging from inflorescence. Broomsedge top of plant.
REED CANARYGRASS
Reed canarygrass patch. Reed canarygrass seeds. Reed canarygrass seedling. Reed canarygrass seedhead.
DEER-TONGUE GRASS
Deer tongue grass patch; note pointed, almost triangular leaves that surround stem. Deer tongue grass seeds. Deer tongue grass seedling. Deer tongue grass inflorescence.
TALL FESCUE
Tall fescue leaf blade and inflorescences. Tall fescue roots and stem base. Tall fescue seeds. Tall fescue seedling.
JOHNSONGRASS
Johnsongrass rhizome. Johnsongrass seeds. Johnsongrass collar region; note prominent midrib of leaf. Johnsongrass inflorescence. Johnsongrass inflorescence along roadside.
NIMBLEWILL
Nimblewill root system with short, scaly rhizomes. Nimblewill seeds. Nimblewill plant with stems reaching in all directions.
ORCHARDGRASS
Orchardgrass stem base showing white, fleshy tillers. Orchardgrass seeds. Orchardgrass inflorescence. Orchardgrass juvenile.
COMMON REED
Common reed in bloom. Common reed roots. Common reed seeds. Common reed's long horizontal stem with shoots at nodes. Common reed inflorescence.
QUACKGRASS
Quackgrass plant base with creeping, sharp-pointed rhizome. Quackgrass seeds. Quackgrass collar region showing clasping auricles. Quackgrass in bloom. Quackgrass shoots in crop residue.
WIRESTEM MUHLY
Wirestem muhly root system with rhizomes. Wirestem muhly seeds. Wirestem muhly inflorescence in full bloom. Wirestem muhly growth habit.
TIMOTHY
Timothy stem base with corm. Timothy seed. Timothy spike in bloom showing exerted anthers. Timothy plants with seed heads.
YELLOW NUTSEDGE
Yellow nutsedge infestation in corn. Yellow nutsedge nutlets. Yellow nutsedge root system with tubers and rhizome. Yellow nutsedge inflorescence top view.
SLENDER RUSH
Slender rush stem base showing shoot buds. Slender rush seeds. Slender rush inflorescence showing developing capsules. Slender rush whole plant.
WILD ASPARAGUS
Wild asparagus berries are shiny red when ripe. Wild asparagus seeds. Wild asparagus shoots emerging in springtime. Wild asparagus shoot tops beginning to branch. Wild asparagus patch along roadside.
TAWNY DAYLILY
Daylily flower. Daylily root system showing swollen roots. Daylily seeds. Daylily shoot.
WILD GARLIC
Individual aerial bulblets. Wild garlic flowers and aerial bulblets. Wild garlic plant base with roots and bulbs. Wild garlic plant growing in a field.
WHITE MULBERRY
Distinctive orange-speckled bark of mulberry. Developing mulberry fruit is a cluster of berries. Mulberry stem showing variation in leaf shape. Mulberry dried fruit and individual seeds. Mulberry seedling with several true leaves.
STINGING NETTLE
Stinging nettle developing flowers and developing fruits. Stinging nettle seeds. Stinging nettle shoots emerging in grass along roadside. Stinging nettle stem is square with stinging hairs, painful to touch.
BROADLEAF DOCK
Common burdock seed capsule (achene) showing toothed margin of wing. Broadleaf dock fruiting stalk. Broadleaf dock rosette. Broadleaf dock seeds. Broadleaf dock stem with sheath (ochrea) at node.
CURLY DOCK
Curly dock fruits (achenes) showing un-notched margin of wing. Curly dock seedlings with 2 to 3 true leaves. Curly dock plant just before bolting. Curly dock flower stalk.
JAPANESE KNOTWEED
Japanese knotweed fruit (achene) with pointed wings. Japanese knotweed invading a soybean field. Japanese knotweed flowers along stem. Japanese knotweed root system with rhizomes. Japanese knotweed seeds. Japanese knotweed shoots emerging from rhizomes.
SWAMP SMARTWEED
Swamp smartweed flower. Base of swamp smartweed plant showing creeping roots. Swamp smartweed seeds. Terrestrial form of swamp smartweed with very hairy stem, sheath (ochrea) and leaves; note the flange at the top of the sheath (variable). Swamp smartweed plant.
RED SORREL
Red sorrel rosette. Red sorrel leaf is arrowhead-shaped with pointed lobes. Red sorrel plant showing creeping rhizomes. Red sorrel seeds. Red sorrel after blooming with seeds forming; red color varies with soil fertility.
WILD FOUR-O'CLOCK
Wild four-o'clock flower cluster showing buds and an open flower. Wild four-o'clock has a large branched taproot, making it nearly impossible to pull up. Wild four-o'clock seeds fall off the plant and germinate right away. After blooming, the fused sepals resemble a star-shaped flower; note seeds in center. Wild four-o'clock plant in field.
COMMON POKEWEED
Common pokeweed berry cluster. A no-till field infested with common pokeweed. Common pokeweed root. Common pokeweed seeds.
BOUNCINGBET
Bouncingbet flower. Bouncingbet seeds. Bouncingbet seedling. Bouncingbet blooming along roadside.
MOUSEEAR CHICKWEED
Mouseear chickweed growth habit. Mouseear chickweed flower has five deeply divided white petals. Mouseear chickweed stem is densely hairy. Mouseear chickweed seeds.
WHITE CAMPION
White campion rosette. White campion seed capsule split to reveal seeds. White campion plant base showing stem arrangement and root. White campion seeds and smooth, woody capsule; other structures are supporting bracts. Female (left) and male (right) flowers of white campion.
CREEPING BUTTERCUP
Creeping buttercup patch. Creeping buttercup flower. Creeping buttercup roots and wiry stolon. Creeping buttercup seed cluster. Creeping buttercup display of blooms in springtime. Growth habit of creeping buttercup showing new crowns initiated along nodes of creeping stolon.
TALL BUTTERCUP
Tall buttercup leaf. Tall buttercup seeds. tall buttercup flower. Tall buttercup plants in bloom along roadside.
GARLIC MUSTARD
Garlic mustard habit in woods. Garlic mustard rosette. Garlic mustard seeds. Garlic mustard flowering stalk.
BRAMBLES
Bramble berries. Brambles growing in no-till corn. Typical bramble flower. Bramble seeds.
COMMON CHOKECHERRY
Ripening berries of common chokecherry. Common chokecherry flower clusters. Dried berry of common chokecherry. Common chokecherry seedling.
ROUGH CINQUEFOIL
Rough cinquefoil flower. Rough cinquefoil leaf is composed of 3 leaflets. Rough cinquefoil seedling with cotyledons and 3 true leaves. Rough cinquefoil habit.
SULFUR CINQUEFOIL
Sulfur cinquefoil flower. Sulfur cinquefoil leaf with 5 leaflets (leaves may have up to 9 leaflets). Sulfur cinquefoil seed pods. Sulfur cinquefoil seeds.
MULTIFLORA ROSE
A cluster of multiflora rose fruit. Close-up of multiflora rose fruit. A close-up of multiflora rose flowers. Multiflora rose seeds. Multiflora rose stem; note the stout thorns. Multiflora rose seedling with cotyledons and 3-4 true leaves.
TRAILING CROWNVETCH
Trailing crownvetch habit. Trailing crownvetch flower cluster; flowers can range in color from white to pink. Trailing crownvetch seeds. Trailing crownvetch seedling with several true leaves.
BLACK LOCUST
Bark of mature black locust. A cluster of black locust flowers. Young black locust. Black locust seedpods and seeds. Black locust seeds.
BIRDSFOOT TREFOIL
Birdsfoot trefoil habit. Individual birdsfoot trefoil plant. Birdsfoot trefoil flower and seedpods. Birdsfoot trefoil seeds.
TREE-OF-HEAVEN
Winged seeds of tree-of-heaven. Clusters of winged seeds of tree-of-heaven. Tree-of-heaven stem. Tree-of-heaven seedling with cotyledons and 2 true leaves. Mature tree-of-heaven.
POISON-IVY
Poison-ivy berries. Poison-ivy flowers. Mature poison-ivy plant growing on a fence. Poison-ivy leaves; note the various shades of green and red. Poison-ivy seeds. Poison-ivy seedling with cotyledons and 2 true leaves (composed of 3 leaflets).
SMOOTH SUMAC
Smooth sumac in no-till corn. Ripe seeds of smooth sumac form a showy cluster. The smooth stem of smooth sumac. Smooth sumac seedling with cotyledons and 2 true leaves.
STAGHORN SUMAC
Staghorn sumac seeds with and without the hairy coating. A hairy cluster of staghorn sumac seeds. The hairy stem of staghorn sumac. The upper stem of staghorn sumac.
BOXELDER
Compound leaf of boxelder. Winged seeds of boxelder. A cluster of winged seeds of boxelder. Older boxelder stem; note the leaf scars, white bloom and tan dots. Young boxelder.
WILD GRAPES
Wild grape stem with leaves and maturing berries. Unripe wild grape berries. Wild grape seeds. Wild grape stem and leaves; note that leaves may have deep lobes. Wild grape seedling with 2 true leaves.
VIRGINIA-CREEPER
Virginia-creeper berries. Virginia-creeper in a no-till corn field. Virginia-creeper seeds. Adhesive oval disks at the end of Virginia-creeper tendrils allow it to climb.
COMMON MALLOW
Common mallow flower. Common mallow habit; note the trailing stems. Stout taproot of common mallow with new shoots developing from the root crown. Common mallow seed.
MUSK MALLOW
Close-up of musk mallow flower. Musk mallow stems. Musk mallow leaf. Musk mallow seeds.
COMMON ST. JOHNSWORT
Close-up of a common St. Johnswort flower. Common St. Johnswort leaves; note the transparent dots on the right leaf and black dots on the tip of the left leaf. Young common St. Johnswort plant. Common St. Johnswort stem in flower.
PURPLE LOOSESTRIFE
Purple loosestrife flowering stem. Purple loosestrife seeds. Purple loosestrife seedling with cotyledons and 6 true leaves. Purple loosestrife in flower; note the many branches.
COMMON EVENINGPRIMROSE
Top view of elongating stem of common eveningprimrose. Close-up of common eveningprimrose flower. Developing seedpods of common eveningprimrose. Common eveningprimrose seeds.
WILD CARROT
Wild carrot flower head. Elongated shoot of second-year wild carrot plant, growing in corn. Rosette of wild carrot. Wild carrot seeds.
WILD PARSNIP
Wild parsnip flower. Wild parsnip fruit. Wild parsnip rosette. Wild parsnip seeds. Older wild parsnip seedling.
POISON-HEMLOCK
Poison hemlock flower head. Poison hemlock seeds. Poison hemlock purple mottled smooth stem. Poison hemlock plant in bloom.
HEMP DOGBANE
Hemp dogbane seed pods hang like a pair of pincers. Hemp dogbane creeping  rootstocks. Hemp dogbane seeds with pappus removed. Hemp dogbane shoots emerging in corn residue. Hemp dogbane in bloom in soybean field.
BUTTERFLY MILKWEED
Butterfly milkweed flower. Butterfly milkweed seedling at cotyledon stage. Butterfly milkweed pods. Butterfly milkweed senescent pod with seeds and attached pappus.
COMMON MILKWEED
Common milkweed flower head. Common milkweed shoot; note opposite leaves. Common milkweed pods (follicles) with prickly surface. Common milkweed seeds.
SWAMP MILKWEED
Swamp milkweed flower; note color variation. Erect seed pods of swamp milkweed. Open ripe seed pod of swamp milkweed with tightly packed seeds. Young swamp milkweed plant.
HONEYVINE MILKWEED
Honeyvine milkweed growing in corn residue. Honeyvine milkweed seed pods (follicles); surface is smooth. Honeyvine milkweed seeds. Honeyvine milkweed seedling.
FIELD BINDWEED
Field bindweed flower; color varies from white to pink. Field bindweed seeds. Field bindweed stem and leaves; note rounded tip, pointed rather than square lobes. Field bindweed in the field.
HEDGE BINDWEED
Hedge bindweed covering the ground and climbing on corn stalks. Hedge bindweed flowers range from white to light pink. Hedge bindweed seeds. Hedge bindweed stem.
JAPANESE BINDWEED
Japanese bindweed flower resembles a small rose, and yields no seeds. Japanese bindweed stem and leaves; note angled leaf lobes. Japanese bindweed shoot emerging in no-till field. Japanese bindweed elongating shoot.
BIGROOT MORNINGGLORY
Bigroot morningglory vines entangled in no-till field. Bigroot morningglory flower. Bigroot morningglory root. Bigroot morningglory seeds.
COMMON COMFREY
Common comfrey infestation in soybeans. Common comfrey flower. Common comfrey taproots and base of plant. Common comfrey flowering plant in soybean field.
BLUE VERVAIN
Blue vervain flowers. Blue vervain leaf; note saw-tooth margins. Blue vervain seeds. Blue vervain in roadside habitat before flowering.
WHITE VERVAIN
White vervain seeds. White vervain flowering stalk with small mint-like white flower. Square, prickly white vervain stem with opposite leaves. Scraggly top of white vervain.
CATNIP
Catnip plants in bloom. Catnip flower stalk. Catnip leaf; note triangular shape, toothed margin, and fuzzy surface. Catnip seeds and individual fruit.
HEALALL
Healall flower. Healall creeping stem with roots at nodes. Healall seeds. Healall fruiting spikes. Healall plants showing creeping growth habit.
GROUND IVY
Ground ivy has a more upright growth habit if it is not mowed. Ground ivy roots at nodes. Ground ivy seeds. Ground ivy seedling with creeping stems.
MOTHERWORT
Motherwort seeds. Motherwort flowers. Motherwort stalks. Motherwort elongating stem.
GROUNDCHERRIES
Smooth groundcherry fruit with calyx torn to reveal berry. Smooth groundcherry plant with lantern-like fruits. Smooth groundcherry flower. Smooth groundcherry seeds.
HORSENETTLE
Horsenettle fruits are a many-seeded berry that turns yellow-orange at maturity. Horsenettle seeds. Horsenettle flowers range in color from white to pink. Horsenettle stems and leaf midribs have sharp spines.
BITTERSWEET NIGHTSHADE
Bittersweet nightshade berries when ripe are shiny red. Bittersweet nightshade flowers are purple, resemble tomato flower. Bittersweet nightshade seeds. Bittersweet nightshade branch with 3-lobed leaves and flowers.
COMMON MULLEIN
Common mullein flower. Common mullein seeds resemble short corn cobs. Common mullein plant starting to bolt; note very furry light green leaves. Common mullein habitat.
MOTH MULLEIN
Moth mullein flowers; colors range from pink to white to yellow. Moth mullein seeds. Moth mullein stems with persistent seed pods that last into winter. Moth mullein rosette.
YELLOW TOADFLAX
Yellow toadflax infestation. Yellow toadflax flower. Yellow toadflax with tip removed to show leaf arrangement. Yellow toadflax seeds.
TRUMPETCREEPER
Trumpetcreeper infestation in corn. Trumpetcreeper flowering stem. Trumpetcreeper leaf. Trumpetcreeper fruit.
BLACKSEED PLANTAIN
Blackseed plantain seeds. Developing fruits along linear stalk of blackseed plantain. Blackseed plantain flowers. Blackseed plantain rosette.
BROADLEAF PLANTAIN
Broadleaf plantain seeds. Broadleaf plantain (left) and blackseed plantain fruiting stalks. Whole plant of broadleaf plantain. Broadleaf plantain rosette before bolting.
BUCKHORN PLANTAIN
Flower stalks of buckhorn plantain. Buckhorn plantain seeds. Senescent seed head of buckhorn plantain. Buckhorn plantain flower head.
SMOOTH BEDSTRAW
Smooth bedstraw fruits. Developing fruits on smooth bedstraw stem. Flowering terminal branch of smooth bedstraw Smooth bedstraw vegetative plant.
AMERICAN ELDER
American elder berries make a good, but seedy pie. American elder flower. Young American elder plant. American elder seeds and one shriveled berry.
JAPANESE HONEYSUCKLE
Japanese honeysuckle berries. Japanese honeysuckle in full bloom; note yellow and white flowers. Japanese honeysuckle flowers. Japanese honeysuckle leaf in autumn.
BUSH HONEYSUCKLES
Red, juicy honeysuckle berry. Tatarian honeysuckle flower. Honeysuckle plant at edge of no-till corn field. Honeysuckle stem with characteristic striped pattern.
COMMON TEASEL
Teasel seeds. Teasel flower head. Dried, persistent stalks of teasel. Teasel rosette; note prickles on leaf surface.
GREAT-BLUE LOBELIA
Greater lobelia terminal inflorescences. Greater lobelia makes a stunning display along the roadside. Greater lobelia seeds. Terminal shoot just before flowering.
JERUSALEM ARTICHOKE
Jerusalem artichoke flower head. Jerusalem artichoke shoots elongating in no-till field. Jerusalem artichoke roots with tubers. Jerusalem artichoke seeds.
WHITE-HEATH ASTER
White heath aster infesting a soybean field. White heath aster flower. White heath aster roots. White heath aster seeds with pappus and persistent petals attached.
COMMON BURDOCK
Common burdock seeds. Common burdock flower heads showing velcro-like spines. Common burdock seed heads persist into winter. Common burdock rosette before bolting.
COMMON CATSEAR
Common catsear flowers at the end of lanky stalks. Common catsear roots. Common catsear seed with pappus attached. Common catsear rosette, easily confused with dandelion, but for the hairy surface.
CHICORY
Chicory flower. Chicory blooming in a soybean field. Chicory seeds. Leaf and stems of chicory.
COLTSFOOT
Coltsfoot flowers, the first yellow flowers of spring, appear well before leaves. Coltsfoot rosette; leaves are thought to resemble a colt's footprint. Senescent coltsfoot flowers, a whitish cluster of pappuses above a green-gray stem. Coltsfoot roots and rhizome.
OXEYE DAISY
Oxeye daisy flower. Oxeye daisy flowers along roadside. Oxeye daisy rosettes. Oxeye daisy seedling at the 5-leaf stage.
DANDELION
Dandelion flowers are a common cheerful sight in turfgrass. Young dandelion rosette. Dandelion seedhead waiting for a breeze. Dandelion seeds without pappus.
CANADA GOLDENROD
Early goldenrod flower. Goldenrod root. Goldenrod seeds. Canada goldenrod stem. Early goldenrod in bloom.
HAWKWEEDS
Hawkweed rosettes clustered together for form a mat. Orange hawkweed flower cluster. Yellow hawkweed flowers. Yellow hawkweed stem. Yellow hawkweed seeds.
TALL IRONWEED
Tall ironweed infesting farm pasture. Tall ironweed seeds. Tall ironweed in flower. Tall ironweed rosette.
JOEPYEWEEDS
Joepyeweed flowers. Joepyeweed seeds with attached pappus. Axillary buds at mid-stem. Terminal buds and upper stem of joepyeweed.
SPOTTED KNAPWEED
Spotted knapweed flower. Young spotted knapweed rosette. Spotted knapweed leaf showing downy, gray-green surface. Spotted knapweed seeds with attached pappus.
PRICKLY LETTUCE
Prickly lettuce flowers. Prickles along midrib on underside of leaf; note clasping lobes at leaf base. Prickly lettuce seeds with attached pappus. Small globe of prickly lettuce seed head, often make a tangled web. Prickly lettuce rosette just before bolting.
MUGWORT
Mugwort flowers, small, inconspicuous, yellow-green. Mugwort seedling. Mugwort roods with section of woody rhizome. Mugwort seeds.
WESTERN SALSIFY
Western salsify flower. Large western salsify seed head among stems and closed flowers. Close-up of achene showing rough texture. Western salsify stems with alternate, linear, upright leaves.
WHITE SNAKEROOT
White snakeroot stem and bloom. Roots of white snakeroot. White snakeroot leaves.
PERENNIAL SOWTHISTLE
Perennial sowthistle flowers. Perennial sowthistle in corn. Leaves of perennial sowthistle are somewhat prickly. Note how the leaf base clasps the stem. Perennial sowthistle roots. Perennial sowthistle seeds.
BULL THISTLE
Bull thistle flower. Bull thistle seeds. Elongated shoot of second-year bull thistle plant. Bull thistle rosette.
CANADA THISTLE
Tiger swallowtail visits Canada thistle. Canada thistle flower. Canada thistle shoot emerging in springtime. Canada thistle seeds. Canada thistle plants before shoot elongation.
COMMON YARROW
Close-up of common yarrow flower cluster. Common yarrow rosette. Common yarrow  seeds. Feathery leaf of common yarrow.